From patchwork Mon Jun 29 19:56:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632019 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 68C8C739 for ; Mon, 29 Jun 2020 20:01:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 533D5206A5 for ; Mon, 29 Jun 2020 20:01:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388459AbgF2UBO (ORCPT ); Mon, 29 Jun 2020 16:01:14 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:33746 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728949AbgF2UBM (ORCPT ); Mon, 29 Jun 2020 16:01:12 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jpzxn-0002lW-5c; Mon, 29 Jun 2020 14:01:11 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jpzxl-0003O1-TR; Mon, 29 Jun 2020 14:01:10 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 14:56:38 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <875zb97iix.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jpzxl-0003O1-TR;;;mid=<875zb97iix.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+rW0kJ/Nu0di7F1+PvK/unH2VPrQ43lAM= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa04.xmission.com X-Spam-Level: X-Spam-Status: No, score=-0.2 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa04 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa04 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 865 ms - load_scoreonly_sql: 0.03 (0.0%), signal_user_changed: 10 (1.2%), b_tie_ro: 9 (1.0%), parse: 0.79 (0.1%), extract_message_metadata: 13 (1.4%), get_uri_detail_list: 1.38 (0.2%), tests_pri_-1000: 23 (2.6%), tests_pri_-950: 1.03 (0.1%), tests_pri_-900: 0.92 (0.1%), tests_pri_-90: 137 (15.8%), check_bayes: 135 (15.7%), b_tokenize: 8 (1.0%), b_tok_get_all: 7 (0.8%), b_comp_prob: 2.0 (0.2%), b_tok_touch_all: 115 (13.3%), b_finish: 0.87 (0.1%), tests_pri_0: 671 (77.5%), check_dkim_signature: 0.53 (0.1%), check_dkim_adsp: 1.65 (0.2%), poll_dns_idle: 0.22 (0.0%), tests_pri_10: 1.76 (0.2%), tests_pri_500: 5 (0.6%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 01/15] umh: Capture the pid in umh_pipe_setup X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The pid in struct subprocess_info is only used by umh_clean_and_save_pid to write the pid into umh_info. Instead always capture the pid on struct umh_info in umh_pipe_setup, removing code that is specific to user mode drivers from the common user path of user mode helpers. Link: https://lkml.kernel.org/r/87h7uygf9i.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umh.h | 1 - kernel/umh.c | 5 ++--- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/include/linux/umh.h b/include/linux/umh.h index 0c08de356d0d..aae16a0ebd0f 100644 --- a/include/linux/umh.h +++ b/include/linux/umh.h @@ -25,7 +25,6 @@ struct subprocess_info { struct file *file; int wait; int retval; - pid_t pid; int (*init)(struct subprocess_info *info, struct cred *new); void (*cleanup)(struct subprocess_info *info); void *data; diff --git a/kernel/umh.c b/kernel/umh.c index 79f139a7ca03..c2a582b3a2bf 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -102,7 +102,6 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); - sub_info->pid = task_pid_nr(current); if (sub_info->file) { retval = do_execve_file(sub_info->file, sub_info->argv, sub_info->envp); @@ -468,6 +467,7 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new) umh_info->pipe_to_umh = to_umh[1]; umh_info->pipe_from_umh = from_umh[0]; + umh_info->pid = task_pid_nr(current); return 0; } @@ -476,13 +476,12 @@ static void umh_clean_and_save_pid(struct subprocess_info *info) struct umh_info *umh_info = info->data; /* cleanup if umh_pipe_setup() was successful but exec failed */ - if (info->pid && info->retval) { + if (info->retval) { fput(umh_info->pipe_to_umh); fput(umh_info->pipe_from_umh); } argv_free(info->argv); - umh_info->pid = info->pid; } /** From patchwork Mon Jun 29 19:57:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632025 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2D5F614E3 for ; Mon, 29 Jun 2020 20:01:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E06C206F1 for ; Mon, 29 Jun 2020 20:01:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388376AbgF2UBh (ORCPT ); Mon, 29 Jun 2020 16:01:37 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:37270 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388122AbgF2UBg (ORCPT ); Mon, 29 Jun 2020 16:01:36 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jpzyB-0005Vb-G4; Mon, 29 Jun 2020 14:01:35 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jpzyA-0007zH-8m; Mon, 29 Jun 2020 14:01:35 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 14:57:03 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87zh8l63xs.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jpzyA-0007zH-8m;;;mid=<87zh8l63xs.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX18tkilkwueNF9nWNOIZyHygLGlNpkZV+hs= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 788 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 10 (1.3%), b_tie_ro: 9 (1.2%), parse: 0.95 (0.1%), extract_message_metadata: 18 (2.3%), get_uri_detail_list: 1.56 (0.2%), tests_pri_-1000: 91 (11.6%), tests_pri_-950: 2.1 (0.3%), tests_pri_-900: 1.79 (0.2%), tests_pri_-90: 290 (36.8%), check_bayes: 286 (36.4%), b_tokenize: 36 (4.5%), b_tok_get_all: 22 (2.8%), b_comp_prob: 2.7 (0.3%), b_tok_touch_all: 221 (28.0%), b_finish: 1.00 (0.1%), tests_pri_0: 337 (42.8%), check_dkim_signature: 0.75 (0.1%), check_dkim_adsp: 2.5 (0.3%), poll_dns_idle: 0.27 (0.0%), tests_pri_10: 3.7 (0.5%), tests_pri_500: 13 (1.6%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 02/15] umh: Move setting PF_UMH into umh_pipe_setup X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: I am separating the code specific to user mode drivers from the code for ordinary user space helpers. Move setting of PF_UMH from call_usermodehelper_exec_async which is core user mode helper code into umh_pipe_setup which is user mode driver code. The code is equally as easy to write in one location as the other and the movement minimizes the impact of the user mode driver code on the core of the user mode helper code. Setting PF_UMH unconditionally is harmless as an action will only happen if it is paired with an entry on umh_list. Link: https://lkml.kernel.org/r/87bll6gf8t.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- kernel/umh.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/umh.c b/kernel/umh.c index c2a582b3a2bf..e6b9d6636850 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -102,12 +102,10 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); - if (sub_info->file) { + if (sub_info->file) retval = do_execve_file(sub_info->file, sub_info->argv, sub_info->envp); - if (!retval) - current->flags |= PF_UMH; - } else + else retval = do_execve(getname_kernel(sub_info->path), (const char __user *const __user *)sub_info->argv, (const char __user *const __user *)sub_info->envp); @@ -468,6 +466,7 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new) umh_info->pipe_to_umh = to_umh[1]; umh_info->pipe_from_umh = from_umh[0]; umh_info->pid = task_pid_nr(current); + current->flags |= PF_UMH; return 0; } From patchwork Mon Jun 29 19:57:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632029 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 889DC739 for ; Mon, 29 Jun 2020 20:02:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B1CC20675 for ; Mon, 29 Jun 2020 20:02:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388558AbgF2UCG (ORCPT ); Mon, 29 Jun 2020 16:02:06 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:34140 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731899AbgF2UCE (ORCPT ); Mon, 29 Jun 2020 16:02:04 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jpzyc-0002sK-UK; Mon, 29 Jun 2020 14:02:03 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jpzyZ-0003Ux-3x; Mon, 29 Jun 2020 14:02:02 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 14:57:28 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87tuyt63x3.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jpzyZ-0003Ux-3x;;;mid=<87tuyt63x3.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX18RpE6R/pGcowgvRUQ2NRyV2B5nU+ocdog= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa01.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Virus: No X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa01 0; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: ; sa01 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 1983 ms - load_scoreonly_sql: 0.21 (0.0%), signal_user_changed: 12 (0.6%), b_tie_ro: 9 (0.5%), parse: 1.84 (0.1%), extract_message_metadata: 114 (5.8%), get_uri_detail_list: 2.2 (0.1%), tests_pri_-1000: 145 (7.3%), compile_eval: 158 (8.0%), tests_pri_-950: 2.5 (0.1%), tests_pri_-900: 26 (1.3%), tests_pri_-90: 191 (9.7%), check_bayes: 176 (8.9%), b_tokenize: 33 (1.7%), b_tok_get_all: 30 (1.5%), b_comp_prob: 2.3 (0.1%), b_tok_touch_all: 99 (5.0%), b_finish: 0.98 (0.0%), tests_pri_0: 1431 (72.2%), check_dkim_signature: 0.92 (0.0%), check_dkim_adsp: 47 (2.4%), poll_dns_idle: 33 (1.7%), tests_pri_10: 2.8 (0.1%), tests_pri_500: 50 (2.5%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 03/15] umh: Rename the user mode driver helpers for clarity X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Now that the functionality of umh_setup_pipe and umh_clean_and_save_pid has changed their names are too specific and don't make much sense. Instead name them umd_setup and umd_cleanup for the functional role in setting up user mode drivers. Link: https://lkml.kernel.org/r/875zbegf82.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- kernel/umh.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/umh.c b/kernel/umh.c index e6b9d6636850..26c3d493f168 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -429,7 +429,7 @@ struct subprocess_info *call_usermodehelper_setup_file(struct file *file, return sub_info; } -static int umh_pipe_setup(struct subprocess_info *info, struct cred *new) +static int umd_setup(struct subprocess_info *info, struct cred *new) { struct umh_info *umh_info = info->data; struct file *from_umh[2]; @@ -470,11 +470,11 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new) return 0; } -static void umh_clean_and_save_pid(struct subprocess_info *info) +static void umd_cleanup(struct subprocess_info *info) { struct umh_info *umh_info = info->data; - /* cleanup if umh_pipe_setup() was successful but exec failed */ + /* cleanup if umh_setup() was successful but exec failed */ if (info->retval) { fput(umh_info->pipe_to_umh); fput(umh_info->pipe_from_umh); @@ -520,8 +520,8 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) } err = -ENOMEM; - sub_info = call_usermodehelper_setup_file(file, umh_pipe_setup, - umh_clean_and_save_pid, info); + sub_info = call_usermodehelper_setup_file(file, umd_setup, umd_cleanup, + info); if (!sub_info) goto out; From patchwork Mon Jun 29 19:59:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632049 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E1A4739 for ; Mon, 29 Jun 2020 20:04:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AD17206A5 for ; Mon, 29 Jun 2020 20:04:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388782AbgF2UDz (ORCPT ); Mon, 29 Jun 2020 16:03:55 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:34946 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388398AbgF2UDv (ORCPT ); Mon, 29 Jun 2020 16:03:51 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq00M-00035w-5W; Mon, 29 Jun 2020 14:03:50 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq00L-0008JW-78; Mon, 29 Jun 2020 14:03:50 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 14:59:18 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87o8p163u1.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq00L-0008JW-78;;;mid=<87o8p163u1.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19S/tg5cEEqB6JiVpZiUOHjZBDa7MQr0pA= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa03.xmission.com X-Spam-Level: * X-Spam-Status: No, score=1.4 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,FVGT_m_MULTI_ODD,T_TM2_M_HEADER_IN_MSG, T_TooManySym_01,T_TooManySym_02,XMGappySubj_01,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Virus: No X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.5 XMGappySubj_01 Very gappy subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 0; Body=1 Fuz1=1 Fuz2=1] * 0.4 FVGT_m_MULTI_ODD Contains multiple odd letter combinations * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.0 T_TooManySym_02 5+ unique symbols in subject X-Spam-DCC: ; sa03 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: *; X-Spam-Relay-Country: X-Spam-Timing: total 571 ms - load_scoreonly_sql: 0.03 (0.0%), signal_user_changed: 3.5 (0.6%), b_tie_ro: 2.5 (0.4%), parse: 0.73 (0.1%), extract_message_metadata: 11 (1.9%), get_uri_detail_list: 1.52 (0.3%), tests_pri_-1000: 18 (3.1%), tests_pri_-950: 0.89 (0.2%), tests_pri_-900: 0.81 (0.1%), tests_pri_-90: 180 (31.6%), check_bayes: 179 (31.3%), b_tokenize: 8 (1.4%), b_tok_get_all: 36 (6.2%), b_comp_prob: 1.67 (0.3%), b_tok_touch_all: 130 (22.7%), b_finish: 0.95 (0.2%), tests_pri_0: 346 (60.6%), check_dkim_signature: 0.42 (0.1%), check_dkim_adsp: 2.6 (0.4%), poll_dns_idle: 0.98 (0.2%), tests_pri_10: 1.77 (0.3%), tests_pri_500: 6 (1.1%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 04/15] umh: Remove call_usermodehelper_setup_file. X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The only caller of call_usermodehelper_setup_file is fork_usermode_blob. In fork_usermode_blob replace call_usermodehelper_setup_file with call_usermodehelper_setup and delete fork_usermodehelper_setup_file. For this to work the argv_free is moved from umh_clean_and_save_pid to fork_usermode_blob. Link: https://lkml.kernel.org/r/87zh8qf0mp.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umh.h | 3 --- kernel/umh.c | 42 +++++++++++------------------------------- 2 files changed, 11 insertions(+), 34 deletions(-) diff --git a/include/linux/umh.h b/include/linux/umh.h index aae16a0ebd0f..de08af00c68a 100644 --- a/include/linux/umh.h +++ b/include/linux/umh.h @@ -39,9 +39,6 @@ call_usermodehelper_setup(const char *path, char **argv, char **envp, int (*init)(struct subprocess_info *info, struct cred *new), void (*cleanup)(struct subprocess_info *), void *data); -struct subprocess_info *call_usermodehelper_setup_file(struct file *file, - int (*init)(struct subprocess_info *info, struct cred *new), - void (*cleanup)(struct subprocess_info *), void *data); struct umh_info { const char *cmdline; struct file *pipe_to_umh; diff --git a/kernel/umh.c b/kernel/umh.c index 26c3d493f168..b8fa9b99b366 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -402,33 +402,6 @@ struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv, } EXPORT_SYMBOL(call_usermodehelper_setup); -struct subprocess_info *call_usermodehelper_setup_file(struct file *file, - int (*init)(struct subprocess_info *info, struct cred *new), - void (*cleanup)(struct subprocess_info *info), void *data) -{ - struct subprocess_info *sub_info; - struct umh_info *info = data; - const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; - - sub_info = kzalloc(sizeof(struct subprocess_info), GFP_KERNEL); - if (!sub_info) - return NULL; - - sub_info->argv = argv_split(GFP_KERNEL, cmdline, NULL); - if (!sub_info->argv) { - kfree(sub_info); - return NULL; - } - - INIT_WORK(&sub_info->work, call_usermodehelper_exec_work); - sub_info->path = "none"; - sub_info->file = file; - sub_info->init = init; - sub_info->cleanup = cleanup; - sub_info->data = data; - return sub_info; -} - static int umd_setup(struct subprocess_info *info, struct cred *new) { struct umh_info *umh_info = info->data; @@ -479,8 +452,6 @@ static void umd_cleanup(struct subprocess_info *info) fput(umh_info->pipe_to_umh); fput(umh_info->pipe_from_umh); } - - argv_free(info->argv); } /** @@ -501,7 +472,9 @@ static void umd_cleanup(struct subprocess_info *info) */ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) { + const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; struct subprocess_info *sub_info; + char **argv = NULL; struct file *file; ssize_t written; loff_t pos = 0; @@ -520,11 +493,16 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) } err = -ENOMEM; - sub_info = call_usermodehelper_setup_file(file, umd_setup, umd_cleanup, - info); + argv = argv_split(GFP_KERNEL, cmdline, NULL); + if (!argv) + goto out; + + sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL, + umd_setup, umd_cleanup, info); if (!sub_info) goto out; + sub_info->file = file; err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); if (!err) { mutex_lock(&umh_list_lock); @@ -532,6 +510,8 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) mutex_unlock(&umh_list_lock); } out: + if (argv) + argv_free(argv); fput(file); return err; } From patchwork Mon Jun 29 20:00:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632055 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D1F192A for ; Mon, 29 Jun 2020 20:05:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FB6F2067D for ; Mon, 29 Jun 2020 20:05:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731993AbgF2UFC (ORCPT ); Mon, 29 Jun 2020 16:05:02 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:35334 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731979AbgF2UFA (ORCPT ); Mon, 29 Jun 2020 16:05:00 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq01S-0003Cg-16; Mon, 29 Jun 2020 14:04:58 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq01Q-0008TW-Cc; Mon, 29 Jun 2020 14:04:57 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:00:25 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87imf963s6.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq01Q-0008TW-Cc;;;mid=<87imf963s6.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+ykOG3gXo6yJeqsDnSIIrix9rU0MsLxLI= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa06.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.9 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,FVGT_m_MULTI_ODD,T_TM2_M_HEADER_IN_MSG,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa06 0; Body=1 Fuz1=1 Fuz2=1] * 0.4 FVGT_m_MULTI_ODD Contains multiple odd letter combinations X-Spam-DCC: ; sa06 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 1017 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 10 (1.0%), b_tie_ro: 9 (0.9%), parse: 1.73 (0.2%), extract_message_metadata: 20 (2.0%), get_uri_detail_list: 7 (0.6%), tests_pri_-1000: 24 (2.3%), tests_pri_-950: 1.30 (0.1%), tests_pri_-900: 1.03 (0.1%), tests_pri_-90: 178 (17.5%), check_bayes: 176 (17.3%), b_tokenize: 26 (2.5%), b_tok_get_all: 14 (1.4%), b_comp_prob: 3.8 (0.4%), b_tok_touch_all: 127 (12.5%), b_finish: 0.95 (0.1%), tests_pri_0: 755 (74.3%), check_dkim_signature: 0.86 (0.1%), check_dkim_adsp: 2.1 (0.2%), poll_dns_idle: 0.55 (0.1%), tests_pri_10: 3.8 (0.4%), tests_pri_500: 18 (1.8%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 05/15] umh: Separate the user mode driver and the user mode helper support X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: This makes it clear which code is part of the core user mode helper support and which code is needed to implement user mode drivers. This makes the kernel smaller for everyone who does not use a usermode driver. v2: Moved exit_umh from sched.h to umd.h and handle the case when the code is compiled out. Link: https://lkml.kernel.org/r/87tuyyf0ln.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/bpfilter.h | 2 +- include/linux/sched.h | 8 --- include/linux/umd.h | 30 ++++++++ include/linux/umh.h | 10 --- kernel/Makefile | 1 + kernel/exit.c | 1 + kernel/umd.c | 146 +++++++++++++++++++++++++++++++++++++++ kernel/umh.c | 139 ------------------------------------- 8 files changed, 179 insertions(+), 158 deletions(-) create mode 100644 include/linux/umd.h create mode 100644 kernel/umd.c diff --git a/include/linux/bpfilter.h b/include/linux/bpfilter.h index d815622cd31e..b42e44e29033 100644 --- a/include/linux/bpfilter.h +++ b/include/linux/bpfilter.h @@ -3,7 +3,7 @@ #define _LINUX_BPFILTER_H #include -#include +#include struct sock; int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval, diff --git a/include/linux/sched.h b/include/linux/sched.h index b62e6aaf28f0..59d1e92bb88e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2020,14 +2020,6 @@ static inline void rseq_execve(struct task_struct *t) #endif -void __exit_umh(struct task_struct *tsk); - -static inline void exit_umh(struct task_struct *tsk) -{ - if (unlikely(tsk->flags & PF_UMH)) - __exit_umh(tsk); -} - #ifdef CONFIG_DEBUG_RSEQ void rseq_syscall(struct pt_regs *regs); diff --git a/include/linux/umd.h b/include/linux/umd.h new file mode 100644 index 000000000000..ef40bee590c1 --- /dev/null +++ b/include/linux/umd.h @@ -0,0 +1,30 @@ +#ifndef __LINUX_UMD_H__ +#define __LINUX_UMD_H__ + +#include + +#ifdef CONFIG_BPFILTER +void __exit_umh(struct task_struct *tsk); + +static inline void exit_umh(struct task_struct *tsk) +{ + if (unlikely(tsk->flags & PF_UMH)) + __exit_umh(tsk); +} +#else +static inline void exit_umh(struct task_struct *tsk) +{ +} +#endif + +struct umh_info { + const char *cmdline; + struct file *pipe_to_umh; + struct file *pipe_from_umh; + struct list_head list; + void (*cleanup)(struct umh_info *info); + pid_t pid; +}; +int fork_usermode_blob(void *data, size_t len, struct umh_info *info); + +#endif /* __LINUX_UMD_H__ */ diff --git a/include/linux/umh.h b/include/linux/umh.h index de08af00c68a..73173c4a07e5 100644 --- a/include/linux/umh.h +++ b/include/linux/umh.h @@ -39,16 +39,6 @@ call_usermodehelper_setup(const char *path, char **argv, char **envp, int (*init)(struct subprocess_info *info, struct cred *new), void (*cleanup)(struct subprocess_info *), void *data); -struct umh_info { - const char *cmdline; - struct file *pipe_to_umh; - struct file *pipe_from_umh; - struct list_head list; - void (*cleanup)(struct umh_info *info); - pid_t pid; -}; -int fork_usermode_blob(void *data, size_t len, struct umh_info *info); - extern int call_usermodehelper_exec(struct subprocess_info *info, int wait); diff --git a/kernel/Makefile b/kernel/Makefile index f3218bc5ec69..a81d7354323c 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -12,6 +12,7 @@ obj-y = fork.o exec_domain.o panic.o \ notifier.o ksysfs.o cred.o reboot.o \ async.o range.o smpboot.o ucount.o +obj-$(CONFIG_BPFILTER) += umd.o obj-$(CONFIG_MODULES) += kmod.o obj-$(CONFIG_MULTIUSER) += groups.o diff --git a/kernel/exit.c b/kernel/exit.c index 727150f28103..b94fe03e609c 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -63,6 +63,7 @@ #include #include #include +#include #include #include diff --git a/kernel/umd.c b/kernel/umd.c new file mode 100644 index 000000000000..99af9d594eca --- /dev/null +++ b/kernel/umd.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * umd - User mode driver support + */ +#include +#include +#include + +static LIST_HEAD(umh_list); +static DEFINE_MUTEX(umh_list_lock); + +static int umd_setup(struct subprocess_info *info, struct cred *new) +{ + struct umh_info *umh_info = info->data; + struct file *from_umh[2]; + struct file *to_umh[2]; + int err; + + /* create pipe to send data to umh */ + err = create_pipe_files(to_umh, 0); + if (err) + return err; + err = replace_fd(0, to_umh[0], 0); + fput(to_umh[0]); + if (err < 0) { + fput(to_umh[1]); + return err; + } + + /* create pipe to receive data from umh */ + err = create_pipe_files(from_umh, 0); + if (err) { + fput(to_umh[1]); + replace_fd(0, NULL, 0); + return err; + } + err = replace_fd(1, from_umh[1], 0); + fput(from_umh[1]); + if (err < 0) { + fput(to_umh[1]); + replace_fd(0, NULL, 0); + fput(from_umh[0]); + return err; + } + + umh_info->pipe_to_umh = to_umh[1]; + umh_info->pipe_from_umh = from_umh[0]; + umh_info->pid = task_pid_nr(current); + current->flags |= PF_UMH; + return 0; +} + +static void umd_cleanup(struct subprocess_info *info) +{ + struct umh_info *umh_info = info->data; + + /* cleanup if umh_setup() was successful but exec failed */ + if (info->retval) { + fput(umh_info->pipe_to_umh); + fput(umh_info->pipe_from_umh); + } +} + +/** + * fork_usermode_blob - fork a blob of bytes as a usermode process + * @data: a blob of bytes that can be do_execv-ed as a file + * @len: length of the blob + * @info: information about usermode process (shouldn't be NULL) + * + * If info->cmdline is set it will be used as command line for the + * user process, else "usermodehelper" is used. + * + * Returns either negative error or zero which indicates success + * in executing a blob of bytes as a usermode process. In such + * case 'struct umh_info *info' is populated with two pipes + * and a pid of the process. The caller is responsible for health + * check of the user process, killing it via pid, and closing the + * pipes when user process is no longer needed. + */ +int fork_usermode_blob(void *data, size_t len, struct umh_info *info) +{ + const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; + struct subprocess_info *sub_info; + char **argv = NULL; + struct file *file; + ssize_t written; + loff_t pos = 0; + int err; + + file = shmem_kernel_file_setup("", len, 0); + if (IS_ERR(file)) + return PTR_ERR(file); + + written = kernel_write(file, data, len, &pos); + if (written != len) { + err = written; + if (err >= 0) + err = -ENOMEM; + goto out; + } + + err = -ENOMEM; + argv = argv_split(GFP_KERNEL, cmdline, NULL); + if (!argv) + goto out; + + sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL, + umd_setup, umd_cleanup, info); + if (!sub_info) + goto out; + + sub_info->file = file; + err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); + if (!err) { + mutex_lock(&umh_list_lock); + list_add(&info->list, &umh_list); + mutex_unlock(&umh_list_lock); + } +out: + if (argv) + argv_free(argv); + fput(file); + return err; +} +EXPORT_SYMBOL_GPL(fork_usermode_blob); + +void __exit_umh(struct task_struct *tsk) +{ + struct umh_info *info; + pid_t pid = tsk->pid; + + mutex_lock(&umh_list_lock); + list_for_each_entry(info, &umh_list, list) { + if (info->pid == pid) { + list_del(&info->list); + mutex_unlock(&umh_list_lock); + goto out; + } + } + mutex_unlock(&umh_list_lock); + return; +out: + if (info->cleanup) + info->cleanup(info); +} + diff --git a/kernel/umh.c b/kernel/umh.c index b8fa9b99b366..3e4e453d45c8 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -26,8 +26,6 @@ #include #include #include -#include -#include #include @@ -38,8 +36,6 @@ static kernel_cap_t usermodehelper_bset = CAP_FULL_SET; static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET; static DEFINE_SPINLOCK(umh_sysctl_lock); static DECLARE_RWSEM(umhelper_sem); -static LIST_HEAD(umh_list); -static DEFINE_MUTEX(umh_list_lock); static void call_usermodehelper_freeinfo(struct subprocess_info *info) { @@ -402,121 +398,6 @@ struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv, } EXPORT_SYMBOL(call_usermodehelper_setup); -static int umd_setup(struct subprocess_info *info, struct cred *new) -{ - struct umh_info *umh_info = info->data; - struct file *from_umh[2]; - struct file *to_umh[2]; - int err; - - /* create pipe to send data to umh */ - err = create_pipe_files(to_umh, 0); - if (err) - return err; - err = replace_fd(0, to_umh[0], 0); - fput(to_umh[0]); - if (err < 0) { - fput(to_umh[1]); - return err; - } - - /* create pipe to receive data from umh */ - err = create_pipe_files(from_umh, 0); - if (err) { - fput(to_umh[1]); - replace_fd(0, NULL, 0); - return err; - } - err = replace_fd(1, from_umh[1], 0); - fput(from_umh[1]); - if (err < 0) { - fput(to_umh[1]); - replace_fd(0, NULL, 0); - fput(from_umh[0]); - return err; - } - - umh_info->pipe_to_umh = to_umh[1]; - umh_info->pipe_from_umh = from_umh[0]; - umh_info->pid = task_pid_nr(current); - current->flags |= PF_UMH; - return 0; -} - -static void umd_cleanup(struct subprocess_info *info) -{ - struct umh_info *umh_info = info->data; - - /* cleanup if umh_setup() was successful but exec failed */ - if (info->retval) { - fput(umh_info->pipe_to_umh); - fput(umh_info->pipe_from_umh); - } -} - -/** - * fork_usermode_blob - fork a blob of bytes as a usermode process - * @data: a blob of bytes that can be do_execv-ed as a file - * @len: length of the blob - * @info: information about usermode process (shouldn't be NULL) - * - * If info->cmdline is set it will be used as command line for the - * user process, else "usermodehelper" is used. - * - * Returns either negative error or zero which indicates success - * in executing a blob of bytes as a usermode process. In such - * case 'struct umh_info *info' is populated with two pipes - * and a pid of the process. The caller is responsible for health - * check of the user process, killing it via pid, and closing the - * pipes when user process is no longer needed. - */ -int fork_usermode_blob(void *data, size_t len, struct umh_info *info) -{ - const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; - struct subprocess_info *sub_info; - char **argv = NULL; - struct file *file; - ssize_t written; - loff_t pos = 0; - int err; - - file = shmem_kernel_file_setup("", len, 0); - if (IS_ERR(file)) - return PTR_ERR(file); - - written = kernel_write(file, data, len, &pos); - if (written != len) { - err = written; - if (err >= 0) - err = -ENOMEM; - goto out; - } - - err = -ENOMEM; - argv = argv_split(GFP_KERNEL, cmdline, NULL); - if (!argv) - goto out; - - sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL, - umd_setup, umd_cleanup, info); - if (!sub_info) - goto out; - - sub_info->file = file; - err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); - if (!err) { - mutex_lock(&umh_list_lock); - list_add(&info->list, &umh_list); - mutex_unlock(&umh_list_lock); - } -out: - if (argv) - argv_free(argv); - fput(file); - return err; -} -EXPORT_SYMBOL_GPL(fork_usermode_blob); - /** * call_usermodehelper_exec - start a usermode application * @sub_info: information about the subprocessa @@ -678,26 +559,6 @@ static int proc_cap_handler(struct ctl_table *table, int write, return 0; } -void __exit_umh(struct task_struct *tsk) -{ - struct umh_info *info; - pid_t pid = tsk->pid; - - mutex_lock(&umh_list_lock); - list_for_each_entry(info, &umh_list, list) { - if (info->pid == pid) { - list_del(&info->list); - mutex_unlock(&umh_list_lock); - goto out; - } - } - mutex_unlock(&umh_list_lock); - return; -out: - if (info->cleanup) - info->cleanup(info); -} - struct ctl_table usermodehelper_table[] = { { .procname = "bset", From patchwork Mon Jun 29 20:01:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632065 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5ECB0138C for ; Mon, 29 Jun 2020 20:06:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A9312082F for ; Mon, 29 Jun 2020 20:06:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388800AbgF2UGf (ORCPT ); Mon, 29 Jun 2020 16:06:35 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:35920 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388859AbgF2UGc (ORCPT ); Mon, 29 Jun 2020 16:06:32 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq02t-0003N6-VO; Mon, 29 Jun 2020 14:06:28 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq02s-0000GO-Gg; Mon, 29 Jun 2020 14:06:27 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:01:55 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <878sg563po.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq02s-0000GO-Gg;;;mid=<878sg563po.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/xzYzSGIoZRKG59bBBeB+kZ2XZYfxfOB4= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa05.xmission.com X-Spam-Level: X-Spam-Status: No, score=-0.2 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa05 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa05 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 1035 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 11 (1.0%), b_tie_ro: 9 (0.9%), parse: 1.02 (0.1%), extract_message_metadata: 15 (1.4%), get_uri_detail_list: 2.6 (0.3%), tests_pri_-1000: 24 (2.3%), tests_pri_-950: 1.15 (0.1%), tests_pri_-900: 0.99 (0.1%), tests_pri_-90: 287 (27.7%), check_bayes: 286 (27.6%), b_tokenize: 12 (1.2%), b_tok_get_all: 8 (0.8%), b_comp_prob: 2.6 (0.3%), b_tok_touch_all: 259 (25.1%), b_finish: 0.65 (0.1%), tests_pri_0: 685 (66.2%), check_dkim_signature: 0.56 (0.1%), check_dkim_adsp: 2.3 (0.2%), poll_dns_idle: 0.69 (0.1%), tests_pri_10: 1.75 (0.2%), tests_pri_500: 5 (0.5%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 06/15] umd: For clarity rename umh_info umd_info X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: This structure is only used for user mode drivers so change the prefix from umh to umd to make that clear. Link: https://lkml.kernel.org/r/87o8p6f0kw.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/bpfilter.h | 2 +- include/linux/umd.h | 6 +++--- kernel/umd.c | 20 ++++++++++---------- net/ipv4/bpfilter/sockopt.c | 2 +- 4 files changed, 15 insertions(+), 15 deletions(-) diff --git a/include/linux/bpfilter.h b/include/linux/bpfilter.h index b42e44e29033..4b43d2240172 100644 --- a/include/linux/bpfilter.h +++ b/include/linux/bpfilter.h @@ -11,7 +11,7 @@ int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval, int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen); struct bpfilter_umh_ops { - struct umh_info info; + struct umd_info info; /* since ip_getsockopt() can run in parallel, serialize access to umh */ struct mutex lock; int (*sockopt)(struct sock *sk, int optname, diff --git a/include/linux/umd.h b/include/linux/umd.h index ef40bee590c1..58a9c603c78d 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -17,14 +17,14 @@ static inline void exit_umh(struct task_struct *tsk) } #endif -struct umh_info { +struct umd_info { const char *cmdline; struct file *pipe_to_umh; struct file *pipe_from_umh; struct list_head list; - void (*cleanup)(struct umh_info *info); + void (*cleanup)(struct umd_info *info); pid_t pid; }; -int fork_usermode_blob(void *data, size_t len, struct umh_info *info); +int fork_usermode_blob(void *data, size_t len, struct umd_info *info); #endif /* __LINUX_UMD_H__ */ diff --git a/kernel/umd.c b/kernel/umd.c index 99af9d594eca..f7dacb19c705 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -11,7 +11,7 @@ static DEFINE_MUTEX(umh_list_lock); static int umd_setup(struct subprocess_info *info, struct cred *new) { - struct umh_info *umh_info = info->data; + struct umd_info *umd_info = info->data; struct file *from_umh[2]; struct file *to_umh[2]; int err; @@ -43,21 +43,21 @@ static int umd_setup(struct subprocess_info *info, struct cred *new) return err; } - umh_info->pipe_to_umh = to_umh[1]; - umh_info->pipe_from_umh = from_umh[0]; - umh_info->pid = task_pid_nr(current); + umd_info->pipe_to_umh = to_umh[1]; + umd_info->pipe_from_umh = from_umh[0]; + umd_info->pid = task_pid_nr(current); current->flags |= PF_UMH; return 0; } static void umd_cleanup(struct subprocess_info *info) { - struct umh_info *umh_info = info->data; + struct umd_info *umd_info = info->data; /* cleanup if umh_setup() was successful but exec failed */ if (info->retval) { - fput(umh_info->pipe_to_umh); - fput(umh_info->pipe_from_umh); + fput(umd_info->pipe_to_umh); + fput(umd_info->pipe_from_umh); } } @@ -72,12 +72,12 @@ static void umd_cleanup(struct subprocess_info *info) * * Returns either negative error or zero which indicates success * in executing a blob of bytes as a usermode process. In such - * case 'struct umh_info *info' is populated with two pipes + * case 'struct umd_info *info' is populated with two pipes * and a pid of the process. The caller is responsible for health * check of the user process, killing it via pid, and closing the * pipes when user process is no longer needed. */ -int fork_usermode_blob(void *data, size_t len, struct umh_info *info) +int fork_usermode_blob(void *data, size_t len, struct umd_info *info) { const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; struct subprocess_info *sub_info; @@ -126,7 +126,7 @@ EXPORT_SYMBOL_GPL(fork_usermode_blob); void __exit_umh(struct task_struct *tsk) { - struct umh_info *info; + struct umd_info *info; pid_t pid = tsk->pid; mutex_lock(&umh_list_lock); diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c index 0480918bfc7c..c0dbcc86fcdb 100644 --- a/net/ipv4/bpfilter/sockopt.c +++ b/net/ipv4/bpfilter/sockopt.c @@ -12,7 +12,7 @@ struct bpfilter_umh_ops bpfilter_ops; EXPORT_SYMBOL_GPL(bpfilter_ops); -static void bpfilter_umh_cleanup(struct umh_info *info) +static void bpfilter_umh_cleanup(struct umd_info *info) { mutex_lock(&bpfilter_ops.lock); bpfilter_ops.stop = true; From patchwork Mon Jun 29 20:02:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632071 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D9D2513B4 for ; Mon, 29 Jun 2020 20:07:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C255920760 for ; Mon, 29 Jun 2020 20:07:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388614AbgF2UHC (ORCPT ); Mon, 29 Jun 2020 16:07:02 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:36126 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732757AbgF2UHB (ORCPT ); Mon, 29 Jun 2020 16:07:01 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq03P-0003QP-La; Mon, 29 Jun 2020 14:06:59 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq03O-00044y-HS; Mon, 29 Jun 2020 14:06:59 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:02:27 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87366d63os.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq03O-00044y-HS;;;mid=<87366d63os.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19gwZGq9LfYG7qMeJVaSLTCNUd+z0ghDAE= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa04.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01, T_TooManySym_02,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.4999] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa04 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.0 T_TooManySym_02 5+ unique symbols in subject X-Spam-DCC: ; sa04 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 752 ms - load_scoreonly_sql: 0.13 (0.0%), signal_user_changed: 13 (1.7%), b_tie_ro: 11 (1.4%), parse: 2.4 (0.3%), extract_message_metadata: 26 (3.4%), get_uri_detail_list: 4.6 (0.6%), tests_pri_-1000: 21 (2.8%), tests_pri_-950: 1.05 (0.1%), tests_pri_-900: 0.93 (0.1%), tests_pri_-90: 317 (42.1%), check_bayes: 314 (41.8%), b_tokenize: 10 (1.3%), b_tok_get_all: 9 (1.2%), b_comp_prob: 2.5 (0.3%), b_tok_touch_all: 288 (38.3%), b_finish: 1.43 (0.2%), tests_pri_0: 349 (46.4%), check_dkim_signature: 0.92 (0.1%), check_dkim_adsp: 2.2 (0.3%), poll_dns_idle: 0.37 (0.0%), tests_pri_10: 4.4 (0.6%), tests_pri_500: 13 (1.7%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 07/15] umd: Rename umd_info.cmdline umd_info.driver_name X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The only thing supplied in the cmdline today is the driver name so rename the field to clarify the code. As this value is always supplied stop trying to handle the case of a NULL cmdline. Additionally since we now have a name we can count on use the driver_name any place where the code is looking for a name of the binary. Link: https://lkml.kernel.org/r/87imfef0k3.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umd.h | 2 +- kernel/umd.c | 11 ++++------- net/ipv4/bpfilter/sockopt.c | 2 +- 3 files changed, 6 insertions(+), 9 deletions(-) diff --git a/include/linux/umd.h b/include/linux/umd.h index 58a9c603c78d..d827fb038d00 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -18,7 +18,7 @@ static inline void exit_umh(struct task_struct *tsk) #endif struct umd_info { - const char *cmdline; + const char *driver_name; struct file *pipe_to_umh; struct file *pipe_from_umh; struct list_head list; diff --git a/kernel/umd.c b/kernel/umd.c index f7dacb19c705..7fe08a8eb231 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -67,9 +67,6 @@ static void umd_cleanup(struct subprocess_info *info) * @len: length of the blob * @info: information about usermode process (shouldn't be NULL) * - * If info->cmdline is set it will be used as command line for the - * user process, else "usermodehelper" is used. - * * Returns either negative error or zero which indicates success * in executing a blob of bytes as a usermode process. In such * case 'struct umd_info *info' is populated with two pipes @@ -79,7 +76,6 @@ static void umd_cleanup(struct subprocess_info *info) */ int fork_usermode_blob(void *data, size_t len, struct umd_info *info) { - const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; struct subprocess_info *sub_info; char **argv = NULL; struct file *file; @@ -87,7 +83,7 @@ int fork_usermode_blob(void *data, size_t len, struct umd_info *info) loff_t pos = 0; int err; - file = shmem_kernel_file_setup("", len, 0); + file = shmem_kernel_file_setup(info->driver_name, len, 0); if (IS_ERR(file)) return PTR_ERR(file); @@ -100,11 +96,12 @@ int fork_usermode_blob(void *data, size_t len, struct umd_info *info) } err = -ENOMEM; - argv = argv_split(GFP_KERNEL, cmdline, NULL); + argv = argv_split(GFP_KERNEL, info->driver_name, NULL); if (!argv) goto out; - sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL, + sub_info = call_usermodehelper_setup(info->driver_name, argv, NULL, + GFP_KERNEL, umd_setup, umd_cleanup, info); if (!sub_info) goto out; diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c index c0dbcc86fcdb..5050de28333d 100644 --- a/net/ipv4/bpfilter/sockopt.c +++ b/net/ipv4/bpfilter/sockopt.c @@ -70,7 +70,7 @@ static int __init bpfilter_sockopt_init(void) { mutex_init(&bpfilter_ops.lock); bpfilter_ops.stop = true; - bpfilter_ops.info.cmdline = "bpfilter_umh"; + bpfilter_ops.info.driver_name = "bpfilter_umh"; bpfilter_ops.info.cleanup = &bpfilter_umh_cleanup; return 0; From patchwork Mon Jun 29 20:03:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632075 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 38C7E913 for ; Mon, 29 Jun 2020 20:07:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1D07E207E8 for ; Mon, 29 Jun 2020 20:07:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388912AbgF2UHp (ORCPT ); Mon, 29 Jun 2020 16:07:45 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:39578 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388905AbgF2UHp (ORCPT ); Mon, 29 Jun 2020 16:07:45 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq047-0006AH-D6; Mon, 29 Jun 2020 14:07:43 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq045-0004Ar-Uk; Mon, 29 Jun 2020 14:07:43 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:03:10 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87wo3p4p35.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq045-0004Ar-Uk;;;mid=<87wo3p4p35.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX181qpo/p82KflUzkNI/ibXfHEB+3fTggUA= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 916 ms - load_scoreonly_sql: 0.06 (0.0%), signal_user_changed: 11 (1.2%), b_tie_ro: 9 (1.0%), parse: 1.35 (0.1%), extract_message_metadata: 18 (2.0%), get_uri_detail_list: 4.9 (0.5%), tests_pri_-1000: 25 (2.7%), tests_pri_-950: 1.31 (0.1%), tests_pri_-900: 1.12 (0.1%), tests_pri_-90: 273 (29.8%), check_bayes: 271 (29.6%), b_tokenize: 20 (2.2%), b_tok_get_all: 11 (1.2%), b_comp_prob: 3.7 (0.4%), b_tok_touch_all: 232 (25.3%), b_finish: 1.00 (0.1%), tests_pri_0: 571 (62.3%), check_dkim_signature: 0.69 (0.1%), check_dkim_adsp: 2.2 (0.2%), poll_dns_idle: 0.52 (0.1%), tests_pri_10: 2.7 (0.3%), tests_pri_500: 9 (1.0%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 08/15] umd: Transform fork_usermode_blob into fork_usermode_driver X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Instead of loading a binary blob into a temporary file with shmem_kernel_file_setup load a binary blob into a temporary tmpfs filesystem. This means that the blob can be stored in an init section and discared, and it means the binary blob will have a filename so can be executed normally. The only tricky thing about this code is that in the helper function blob_to_mnt __fput_sync is used. That is because a file can not be executed if it is still open for write, and the ordinary delayed close for kernel threads does not happen soon enough, which causes the following exec to fail. The function umd_load_blob is not called with any locks so this should be safe. Executing the blob normally winds up correcting several problems with the user mode driver code discovered by Tetsuo Handa[1]. By passing an ordinary filename into the exec, it is no longer necessary to figure out how to turn a O_RDWR file descriptor into a properly referende counted O_EXEC file descriptor that forbids all writes. For path based LSMs there are no new special cases. [1] https://lore.kernel.org/linux-fsdevel/2a8775b4-1dd5-9d5c-aa42-9872445e0942@i-love.sakura.ne.jp/ Link: https://lkml.kernel.org/r/87d05mf0j9.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umd.h | 6 +- kernel/umd.c | 126 +++++++++++++++++++++++++++-------- net/bpfilter/bpfilter_kern.c | 14 +++- 3 files changed, 113 insertions(+), 33 deletions(-) diff --git a/include/linux/umd.h b/include/linux/umd.h index d827fb038d00..12ff8f753ea7 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -2,6 +2,7 @@ #define __LINUX_UMD_H__ #include +#include #ifdef CONFIG_BPFILTER void __exit_umh(struct task_struct *tsk); @@ -23,8 +24,11 @@ struct umd_info { struct file *pipe_from_umh; struct list_head list; void (*cleanup)(struct umd_info *info); + struct path wd; pid_t pid; }; -int fork_usermode_blob(void *data, size_t len, struct umd_info *info); +int umd_load_blob(struct umd_info *info, const void *data, size_t len); +int umd_unload_blob(struct umd_info *info); +int fork_usermode_driver(struct umd_info *info); #endif /* __LINUX_UMD_H__ */ diff --git a/kernel/umd.c b/kernel/umd.c index 7fe08a8eb231..aaa6f3142e52 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -4,11 +4,98 @@ */ #include #include +#include +#include +#include #include static LIST_HEAD(umh_list); static DEFINE_MUTEX(umh_list_lock); +static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *name) +{ + struct file_system_type *type; + struct vfsmount *mnt; + struct file *file; + ssize_t written; + loff_t pos = 0; + + type = get_fs_type("tmpfs"); + if (!type) + return ERR_PTR(-ENODEV); + + mnt = kern_mount(type); + put_filesystem(type); + if (IS_ERR(mnt)) + return mnt; + + file = file_open_root(mnt->mnt_root, mnt, name, O_CREAT | O_WRONLY, 0700); + if (IS_ERR(file)) { + mntput(mnt); + return ERR_CAST(file); + } + + written = kernel_write(file, data, len, &pos); + if (written != len) { + int err = written; + if (err >= 0) + err = -ENOMEM; + filp_close(file, NULL); + mntput(mnt); + return ERR_PTR(err); + } + + fput(file); + + /* Flush delayed fput so exec can open the file read-only */ + flush_delayed_fput(); + task_work_run(); + return mnt; +} + +/** + * umd_load_blob - Remember a blob of bytes for fork_usermode_driver + * @info: information about usermode driver + * @data: a blob of bytes that can be executed as a file + * @len: The lentgh of the blob + * + */ +int umd_load_blob(struct umd_info *info, const void *data, size_t len) +{ + struct vfsmount *mnt; + + if (WARN_ON_ONCE(info->wd.dentry || info->wd.mnt)) + return -EBUSY; + + mnt = blob_to_mnt(data, len, info->driver_name); + if (IS_ERR(mnt)) + return PTR_ERR(mnt); + + info->wd.mnt = mnt; + info->wd.dentry = mnt->mnt_root; + return 0; +} +EXPORT_SYMBOL_GPL(umd_load_blob); + +/** + * umd_unload_blob - Disassociate @info from a previously loaded blob + * @info: information about usermode driver + * + */ +int umd_unload_blob(struct umd_info *info) +{ + if (WARN_ON_ONCE(!info->wd.mnt || + !info->wd.dentry || + info->wd.mnt->mnt_root != info->wd.dentry)) + return -EINVAL; + + kern_unmount(info->wd.mnt); + info->wd.mnt = NULL; + info->wd.dentry = NULL; + return 0; +} +EXPORT_SYMBOL_GPL(umd_unload_blob); + static int umd_setup(struct subprocess_info *info, struct cred *new) { struct umd_info *umd_info = info->data; @@ -43,6 +130,7 @@ static int umd_setup(struct subprocess_info *info, struct cred *new) return err; } + set_fs_pwd(current->fs, &umd_info->wd); umd_info->pipe_to_umh = to_umh[1]; umd_info->pipe_from_umh = from_umh[0]; umd_info->pid = task_pid_nr(current); @@ -62,39 +150,21 @@ static void umd_cleanup(struct subprocess_info *info) } /** - * fork_usermode_blob - fork a blob of bytes as a usermode process - * @data: a blob of bytes that can be do_execv-ed as a file - * @len: length of the blob - * @info: information about usermode process (shouldn't be NULL) + * fork_usermode_driver - fork a usermode driver + * @info: information about usermode driver (shouldn't be NULL) * - * Returns either negative error or zero which indicates success - * in executing a blob of bytes as a usermode process. In such - * case 'struct umd_info *info' is populated with two pipes - * and a pid of the process. The caller is responsible for health - * check of the user process, killing it via pid, and closing the - * pipes when user process is no longer needed. + * Returns either negative error or zero which indicates success in + * executing a usermode driver. In such case 'struct umd_info *info' + * is populated with two pipes and a pid of the process. The caller is + * responsible for health check of the user process, killing it via + * pid, and closing the pipes when user process is no longer needed. */ -int fork_usermode_blob(void *data, size_t len, struct umd_info *info) +int fork_usermode_driver(struct umd_info *info) { struct subprocess_info *sub_info; char **argv = NULL; - struct file *file; - ssize_t written; - loff_t pos = 0; int err; - file = shmem_kernel_file_setup(info->driver_name, len, 0); - if (IS_ERR(file)) - return PTR_ERR(file); - - written = kernel_write(file, data, len, &pos); - if (written != len) { - err = written; - if (err >= 0) - err = -ENOMEM; - goto out; - } - err = -ENOMEM; argv = argv_split(GFP_KERNEL, info->driver_name, NULL); if (!argv) @@ -106,7 +176,6 @@ int fork_usermode_blob(void *data, size_t len, struct umd_info *info) if (!sub_info) goto out; - sub_info->file = file; err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); if (!err) { mutex_lock(&umh_list_lock); @@ -116,10 +185,9 @@ int fork_usermode_blob(void *data, size_t len, struct umd_info *info) out: if (argv) argv_free(argv); - fput(file); return err; } -EXPORT_SYMBOL_GPL(fork_usermode_blob); +EXPORT_SYMBOL_GPL(fork_usermode_driver); void __exit_umh(struct task_struct *tsk) { diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index c0f0990f30b6..28883b00609d 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -77,9 +77,7 @@ static int start_umh(void) int err; /* fork usermode process */ - err = fork_usermode_blob(&bpfilter_umh_start, - &bpfilter_umh_end - &bpfilter_umh_start, - &bpfilter_ops.info); + err = fork_usermode_driver(&bpfilter_ops.info); if (err) return err; bpfilter_ops.stop = false; @@ -98,6 +96,12 @@ static int __init load_umh(void) { int err; + err = umd_load_blob(&bpfilter_ops.info, + &bpfilter_umh_start, + &bpfilter_umh_end - &bpfilter_umh_start); + if (err) + return err; + mutex_lock(&bpfilter_ops.lock); if (!bpfilter_ops.stop) { err = -EFAULT; @@ -110,6 +114,8 @@ static int __init load_umh(void) } out: mutex_unlock(&bpfilter_ops.lock); + if (err) + umd_unload_blob(&bpfilter_ops.info); return err; } @@ -122,6 +128,8 @@ static void __exit fini_umh(void) bpfilter_ops.sockopt = NULL; } mutex_unlock(&bpfilter_ops.lock); + + umd_unload_blob(&bpfilter_ops.info); } module_init(load_umh); module_exit(fini_umh); From patchwork Mon Jun 29 20:03:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632079 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C5C5B913 for ; Mon, 29 Jun 2020 20:08:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7238207D0 for ; Mon, 29 Jun 2020 20:08:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732931AbgF2UIQ (ORCPT ); Mon, 29 Jun 2020 16:08:16 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:36630 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732373AbgF2UIP (ORCPT ); Mon, 29 Jun 2020 16:08:15 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq04c-0003ZM-3v; Mon, 29 Jun 2020 14:08:14 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq04b-0000Ts-2E; Mon, 29 Jun 2020 14:08:13 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:03:41 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87r1tx4p2a.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq04b-0000Ts-2E;;;mid=<87r1tx4p2a.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19IX0qdGDHj2d42J790qFSa6SiJQNy2ip4= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.8 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01,XMSlimDrugH autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 1.0 XMSlimDrugH Weight loss drug headers * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 424 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 9 (2.1%), b_tie_ro: 8 (1.8%), parse: 1.30 (0.3%), extract_message_metadata: 20 (4.7%), get_uri_detail_list: 1.95 (0.5%), tests_pri_-1000: 31 (7.2%), tests_pri_-950: 1.29 (0.3%), tests_pri_-900: 1.00 (0.2%), tests_pri_-90: 115 (27.0%), check_bayes: 112 (26.5%), b_tokenize: 14 (3.3%), b_tok_get_all: 6 (1.5%), b_comp_prob: 2.2 (0.5%), b_tok_touch_all: 86 (20.3%), b_finish: 0.91 (0.2%), tests_pri_0: 233 (55.1%), check_dkim_signature: 0.54 (0.1%), check_dkim_adsp: 2.2 (0.5%), poll_dns_idle: 0.62 (0.1%), tests_pri_10: 2.1 (0.5%), tests_pri_500: 7 (1.6%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 09/15] umh: Stop calling do_execve_file X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: With the user mode driver code changed to not set subprocess_info.file there are no more users of subproces_info.file. Remove this field from struct subprocess_info and remove the only user in call_usermodehelper_exec_async that would call do_execve_file instead of do_execve if file was set. Link: https://lkml.kernel.org/r/877dvuf0i7.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umh.h | 1 - kernel/umh.c | 10 +++------- 2 files changed, 3 insertions(+), 8 deletions(-) diff --git a/include/linux/umh.h b/include/linux/umh.h index 73173c4a07e5..244aff638220 100644 --- a/include/linux/umh.h +++ b/include/linux/umh.h @@ -22,7 +22,6 @@ struct subprocess_info { const char *path; char **argv; char **envp; - struct file *file; int wait; int retval; int (*init)(struct subprocess_info *info, struct cred *new); diff --git a/kernel/umh.c b/kernel/umh.c index 3e4e453d45c8..6ca2096298b9 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -98,13 +98,9 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); - if (sub_info->file) - retval = do_execve_file(sub_info->file, - sub_info->argv, sub_info->envp); - else - retval = do_execve(getname_kernel(sub_info->path), - (const char __user *const __user *)sub_info->argv, - (const char __user *const __user *)sub_info->envp); + retval = do_execve(getname_kernel(sub_info->path), + (const char __user *const __user *)sub_info->argv, + (const char __user *const __user *)sub_info->envp); out: sub_info->retval = retval; /* From patchwork Mon Jun 29 20:04:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632083 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D45C13B4 for ; Mon, 29 Jun 2020 20:09:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A99420826 for ; Mon, 29 Jun 2020 20:09:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727054AbgF2UJX (ORCPT ); Mon, 29 Jun 2020 16:09:23 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:40112 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726943AbgF2UJW (ORCPT ); Mon, 29 Jun 2020 16:09:22 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq05b-0006JU-NI; Mon, 29 Jun 2020 14:09:15 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq05a-0000cx-I2; Mon, 29 Jun 2020 14:09:15 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:04:41 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87lfk54p0m.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq05a-0000cx-I2;;;mid=<87lfk54p0m.fsf_-_@x220.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX18jk9MPy/jYN6RjgP7KmdEpIJ9vTl3XBbc= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: * X-Spam-Status: No, score=1.8 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,TR_XM_PhishingBody,T_TooManySym_01,XM_B_Phish66 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 2.0 XM_B_Phish66 BODY: Obfuscated XMission * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.0 TR_XM_PhishingBody Phishing flag in body of message X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: *; X-Spam-Relay-Country: X-Spam-Timing: total 619 ms - load_scoreonly_sql: 0.06 (0.0%), signal_user_changed: 12 (2.0%), b_tie_ro: 10 (1.6%), parse: 1.62 (0.3%), extract_message_metadata: 29 (4.6%), get_uri_detail_list: 4.8 (0.8%), tests_pri_-1000: 44 (7.1%), tests_pri_-950: 1.37 (0.2%), tests_pri_-900: 0.99 (0.2%), tests_pri_-90: 146 (23.6%), check_bayes: 144 (23.3%), b_tokenize: 17 (2.7%), b_tok_get_all: 12 (1.9%), b_comp_prob: 2.7 (0.4%), b_tok_touch_all: 109 (17.6%), b_finish: 0.94 (0.2%), tests_pri_0: 371 (59.9%), check_dkim_signature: 0.56 (0.1%), check_dkim_adsp: 2.0 (0.3%), poll_dns_idle: 0.59 (0.1%), tests_pri_10: 2.1 (0.3%), tests_pri_500: 7 (1.1%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 10/15] exec: Remove do_execve_file X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Now that the last callser has been removed remove this code from exec. For anyone thinking of resurrecing do_execve_file please note that the code was buggy in several fundamental ways. - It did not ensure the file it was passed was read-only and that deny_write_access had been called on it. Which subtlely breaks invaniants in exec. - The caller of do_execve_file was expected to hold and put a reference to the file, but an extra reference for use by exec was not taken so that when exec put it's reference to the file an underflow occured on the file reference count. - The point of the interface was so that a pathname did not need to exist. Which breaks pathname based LSMs. Tetsuo Handa originally reported these issues[1]. While it was clear that deny_write_access was missing the fundamental incompatibility with the passed in O_RDWR filehandle was not immediately recognized. All of these issues were fixed by modifying the usermode driver code to have a path, so it did not need this hack. Reported-by: Tetsuo Handa [1] https://lore.kernel.org/linux-fsdevel/2a8775b4-1dd5-9d5c-aa42-9872445e0942@i-love.sakura.ne.jp/ Link: https://lkml.kernel.org/r/871rm2f0hi.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- fs/exec.c | 38 +++++++++----------------------------- include/linux/binfmts.h | 1 - 2 files changed, 9 insertions(+), 30 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index e6e8a9a70327..23dfbb820626 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1818,13 +1818,14 @@ static int exec_binprm(struct linux_binprm *bprm) /* * sys_execve() executes a new program. */ -static int __do_execve_file(int fd, struct filename *filename, - struct user_arg_ptr argv, - struct user_arg_ptr envp, - int flags, struct file *file) +static int do_execveat_common(int fd, struct filename *filename, + struct user_arg_ptr argv, + struct user_arg_ptr envp, + int flags) { char *pathbuf = NULL; struct linux_binprm *bprm; + struct file *file; struct files_struct *displaced; int retval; @@ -1863,8 +1864,7 @@ static int __do_execve_file(int fd, struct filename *filename, check_unsafe_exec(bprm); current->in_execve = 1; - if (!file) - file = do_open_execat(fd, filename, flags); + file = do_open_execat(fd, filename, flags); retval = PTR_ERR(file); if (IS_ERR(file)) goto out_unmark; @@ -1872,9 +1872,7 @@ static int __do_execve_file(int fd, struct filename *filename, sched_exec(); bprm->file = file; - if (!filename) { - bprm->filename = "none"; - } else if (fd == AT_FDCWD || filename->name[0] == '/') { + if (fd == AT_FDCWD || filename->name[0] == '/') { bprm->filename = filename->name; } else { if (filename->name[0] == '\0') @@ -1935,8 +1933,7 @@ static int __do_execve_file(int fd, struct filename *filename, task_numa_free(current, false); free_bprm(bprm); kfree(pathbuf); - if (filename) - putname(filename); + putname(filename); if (displaced) put_files_struct(displaced); return retval; @@ -1967,27 +1964,10 @@ static int __do_execve_file(int fd, struct filename *filename, if (displaced) reset_files_struct(displaced); out_ret: - if (filename) - putname(filename); + putname(filename); return retval; } -static int do_execveat_common(int fd, struct filename *filename, - struct user_arg_ptr argv, - struct user_arg_ptr envp, - int flags) -{ - return __do_execve_file(fd, filename, argv, envp, flags, NULL); -} - -int do_execve_file(struct file *file, void *__argv, void *__envp) -{ - struct user_arg_ptr argv = { .ptr.native = __argv }; - struct user_arg_ptr envp = { .ptr.native = __envp }; - - return __do_execve_file(AT_FDCWD, NULL, argv, envp, 0, file); -} - int do_execve(struct filename *filename, const char __user *const __user *__argv, const char __user *const __user *__envp) diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index 4a20b7517dd0..7c27d7b57871 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -141,6 +141,5 @@ extern int do_execveat(int, struct filename *, const char __user * const __user *, const char __user * const __user *, int); -int do_execve_file(struct file *file, void *__argv, void *__envp); #endif /* _LINUX_BINFMTS_H */ From patchwork Mon Jun 29 20:05:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632087 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EE71B913 for ; Mon, 29 Jun 2020 20:10:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DDC7A20809 for ; Mon, 29 Jun 2020 20:10:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728099AbgF2UKG (ORCPT ); Mon, 29 Jun 2020 16:10:06 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:37478 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727071AbgF2UKB (ORCPT ); Mon, 29 Jun 2020 16:10:01 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq06J-0003mh-VX; Mon, 29 Jun 2020 14:09:59 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq06J-0004T6-4B; Mon, 29 Jun 2020 14:09:59 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:05:27 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87ftad4ozc.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq06J-0004T6-4B;;;mid=<87ftad4ozc.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19HJ+Q2cBtWz31Qjezuq/ZK7ROsAlPYjXo= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa04.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa04 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa04 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 398 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 11 (2.8%), b_tie_ro: 9 (2.4%), parse: 1.49 (0.4%), extract_message_metadata: 21 (5.4%), get_uri_detail_list: 2.0 (0.5%), tests_pri_-1000: 29 (7.2%), tests_pri_-950: 1.30 (0.3%), tests_pri_-900: 1.03 (0.3%), tests_pri_-90: 94 (23.7%), check_bayes: 92 (23.1%), b_tokenize: 9 (2.2%), b_tok_get_all: 5 (1.4%), b_comp_prob: 2.0 (0.5%), b_tok_touch_all: 72 (18.1%), b_finish: 1.23 (0.3%), tests_pri_0: 219 (55.1%), check_dkim_signature: 0.75 (0.2%), check_dkim_adsp: 2.1 (0.5%), poll_dns_idle: 0.42 (0.1%), tests_pri_10: 4.1 (1.0%), tests_pri_500: 11 (2.9%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 11/15] bpfilter: Move bpfilter_umh back into init data X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: To allow for restarts 61fbf5933d42 ("net: bpfilter: restart bpfilter_umh when error occurred") moved the blob holding the userspace binary out of the init sections. Now that loading the blob into a filesystem is separate from executing the blob the blob no longer needs to live .rodata to allow for restarting. So move the blob back to .init.rodata. Link: https://lkml.kernel.org/r/87sgeidlvq.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- net/bpfilter/bpfilter_umh_blob.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bpfilter/bpfilter_umh_blob.S b/net/bpfilter/bpfilter_umh_blob.S index 9ea6100dca87..40311d10d2f2 100644 --- a/net/bpfilter/bpfilter_umh_blob.S +++ b/net/bpfilter/bpfilter_umh_blob.S @@ -1,5 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0 */ - .section .rodata, "a" + .section .init.rodata, "a" .global bpfilter_umh_start bpfilter_umh_start: .incbin "net/bpfilter/bpfilter_umh" From patchwork Mon Jun 29 20:06:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632093 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 539B013B4 for ; Mon, 29 Jun 2020 20:10:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 401B420675 for ; Mon, 29 Jun 2020 20:10:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728118AbgF2UKp (ORCPT ); Mon, 29 Jun 2020 16:10:45 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:37826 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729273AbgF2UKm (ORCPT ); Mon, 29 Jun 2020 16:10:42 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq06y-0003sK-H1; Mon, 29 Jun 2020 14:10:40 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq06x-0004aE-1a; Mon, 29 Jun 2020 14:10:39 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:06:07 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87a70l4oy8.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq06x-0004aE-1a;;;mid=<87a70l4oy8.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/x4mrxyEgtfOPj78oDI1znxchawvWVzpY= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa02.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Virus: No X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa02 0; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: ; sa02 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 636 ms - load_scoreonly_sql: 0.03 (0.0%), signal_user_changed: 4.0 (0.6%), b_tie_ro: 2.8 (0.4%), parse: 0.89 (0.1%), extract_message_metadata: 14 (2.2%), get_uri_detail_list: 2.7 (0.4%), tests_pri_-1000: 20 (3.1%), tests_pri_-950: 1.11 (0.2%), tests_pri_-900: 0.85 (0.1%), tests_pri_-90: 164 (25.7%), check_bayes: 162 (25.5%), b_tokenize: 12 (1.9%), b_tok_get_all: 11 (1.7%), b_comp_prob: 2.4 (0.4%), b_tok_touch_all: 134 (21.0%), b_finish: 0.75 (0.1%), tests_pri_0: 421 (66.3%), check_dkim_signature: 0.47 (0.1%), check_dkim_adsp: 2.3 (0.4%), poll_dns_idle: 0.91 (0.1%), tests_pri_10: 1.85 (0.3%), tests_pri_500: 5 (0.8%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 12/15] umd: Track user space drivers with struct pid X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Use struct pid instead of user space pid values that are prone to wrap araound. In addition track the entire thread group instead of just the first thread that is started by exec. There are no multi-threaded user mode drivers today but there is nothing preclucing user drivers from being multi-threaded, so it is just a good idea to track the entire process. Take a reference count on the tgid's in question to make it possible to remove exit_umh in a future change. As a struct pid is available directly use kill_pid_info. The prior process signalling code was iffy in using a userspace pid known to be in the initial pid namespace and then looking up it's task in whatever the current pid namespace is. It worked only because kernel threads always run in the initial pid namespace. As the tgid is now refcounted verify the tgid is NULL at the start of fork_usermode_driver to avoid the possibility of silent pid leaks. Link: https://lkml.kernel.org/r/87mu4qdlv2.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/umd.h | 2 +- kernel/exit.c | 3 ++- kernel/umd.c | 15 ++++++++++----- net/bpfilter/bpfilter_kern.c | 13 +++++-------- net/ipv4/bpfilter/sockopt.c | 3 ++- 5 files changed, 20 insertions(+), 16 deletions(-) diff --git a/include/linux/umd.h b/include/linux/umd.h index 12ff8f753ea7..edb1c62c62f4 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -25,7 +25,7 @@ struct umd_info { struct list_head list; void (*cleanup)(struct umd_info *info); struct path wd; - pid_t pid; + struct pid *tgid; }; int umd_load_blob(struct umd_info *info, const void *data, size_t len); int umd_unload_blob(struct umd_info *info); diff --git a/kernel/exit.c b/kernel/exit.c index b94fe03e609c..b53107abdd31 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -805,7 +805,8 @@ void __noreturn do_exit(long code) exit_task_namespaces(tsk); exit_task_work(tsk); exit_thread(tsk); - exit_umh(tsk); + if (group_dead) + exit_umh(tsk); /* * Flush inherited counters to the parent - before the parent diff --git a/kernel/umd.c b/kernel/umd.c index aaa6f3142e52..c1e8eccaee76 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -133,7 +133,7 @@ static int umd_setup(struct subprocess_info *info, struct cred *new) set_fs_pwd(current->fs, &umd_info->wd); umd_info->pipe_to_umh = to_umh[1]; umd_info->pipe_from_umh = from_umh[0]; - umd_info->pid = task_pid_nr(current); + umd_info->tgid = get_pid(task_tgid(current)); current->flags |= PF_UMH; return 0; } @@ -146,6 +146,8 @@ static void umd_cleanup(struct subprocess_info *info) if (info->retval) { fput(umd_info->pipe_to_umh); fput(umd_info->pipe_from_umh); + put_pid(umd_info->tgid); + umd_info->tgid = NULL; } } @@ -155,9 +157,9 @@ static void umd_cleanup(struct subprocess_info *info) * * Returns either negative error or zero which indicates success in * executing a usermode driver. In such case 'struct umd_info *info' - * is populated with two pipes and a pid of the process. The caller is + * is populated with two pipes and a tgid of the process. The caller is * responsible for health check of the user process, killing it via - * pid, and closing the pipes when user process is no longer needed. + * tgid, and closing the pipes when user process is no longer needed. */ int fork_usermode_driver(struct umd_info *info) { @@ -165,6 +167,9 @@ int fork_usermode_driver(struct umd_info *info) char **argv = NULL; int err; + if (WARN_ON_ONCE(info->tgid)) + return -EBUSY; + err = -ENOMEM; argv = argv_split(GFP_KERNEL, info->driver_name, NULL); if (!argv) @@ -192,11 +197,11 @@ EXPORT_SYMBOL_GPL(fork_usermode_driver); void __exit_umh(struct task_struct *tsk) { struct umd_info *info; - pid_t pid = tsk->pid; + struct pid *tgid = task_tgid(tsk); mutex_lock(&umh_list_lock); list_for_each_entry(info, &umh_list, list) { - if (info->pid == pid) { + if (info->tgid == tgid) { list_del(&info->list); mutex_unlock(&umh_list_lock); goto out; diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index 28883b00609d..b73dedeb6dbf 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -15,16 +15,13 @@ extern char bpfilter_umh_end; static void shutdown_umh(void) { - struct task_struct *tsk; + struct umd_info *info = &bpfilter_ops.info; + struct pid *tgid = info->tgid; if (bpfilter_ops.stop) return; - tsk = get_pid_task(find_vpid(bpfilter_ops.info.pid), PIDTYPE_PID); - if (tsk) { - send_sig(SIGKILL, tsk, 1); - put_task_struct(tsk); - } + kill_pid_info(SIGKILL, SEND_SIG_PRIV, tgid); } static void __stop_umh(void) @@ -48,7 +45,7 @@ static int __bpfilter_process_sockopt(struct sock *sk, int optname, req.cmd = optname; req.addr = (long __force __user)optval; req.len = optlen; - if (!bpfilter_ops.info.pid) + if (!bpfilter_ops.info.tgid) goto out; n = __kernel_write(bpfilter_ops.info.pipe_to_umh, &req, sizeof(req), &pos); @@ -81,7 +78,7 @@ static int start_umh(void) if (err) return err; bpfilter_ops.stop = false; - pr_info("Loaded bpfilter_umh pid %d\n", bpfilter_ops.info.pid); + pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid)); /* health check that usermode process started correctly */ if (__bpfilter_process_sockopt(NULL, 0, NULL, 0, 0) != 0) { diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c index 5050de28333d..56cbc43145f6 100644 --- a/net/ipv4/bpfilter/sockopt.c +++ b/net/ipv4/bpfilter/sockopt.c @@ -18,7 +18,8 @@ static void bpfilter_umh_cleanup(struct umd_info *info) bpfilter_ops.stop = true; fput(info->pipe_to_umh); fput(info->pipe_from_umh); - info->pid = 0; + put_pid(info->tgid); + info->tgid = NULL; mutex_unlock(&bpfilter_ops.lock); } From patchwork Mon Jun 29 20:06:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632097 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 465D1913 for ; Mon, 29 Jun 2020 20:11:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2FBCE206A1 for ; Mon, 29 Jun 2020 20:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730047AbgF2ULc (ORCPT ); Mon, 29 Jun 2020 16:11:32 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:38396 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730003AbgF2ULa (ORCPT ); Mon, 29 Jun 2020 16:11:30 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq07l-00041V-C1; Mon, 29 Jun 2020 14:11:29 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq07k-0004jh-Eh; Mon, 29 Jun 2020 14:11:29 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:06:57 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <874kqt4owu.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq07k-0004jh-Eh;;;mid=<874kqt4owu.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19MtwjAP//3Te8YuqdooC9uWeB4WY4DWYs= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa08.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa08 0; Body=1 Fuz1=1 Fuz2=1] X-Spam-DCC: ; sa08 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 493 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 14 (2.8%), b_tie_ro: 12 (2.4%), parse: 1.53 (0.3%), extract_message_metadata: 18 (3.6%), get_uri_detail_list: 3.4 (0.7%), tests_pri_-1000: 22 (4.4%), tests_pri_-950: 1.29 (0.3%), tests_pri_-900: 1.13 (0.2%), tests_pri_-90: 133 (26.9%), check_bayes: 131 (26.5%), b_tokenize: 12 (2.4%), b_tok_get_all: 12 (2.5%), b_comp_prob: 2.5 (0.5%), b_tok_touch_all: 99 (20.1%), b_finish: 1.25 (0.3%), tests_pri_0: 290 (58.8%), check_dkim_signature: 0.77 (0.2%), check_dkim_adsp: 2.6 (0.5%), poll_dns_idle: 0.96 (0.2%), tests_pri_10: 2.5 (0.5%), tests_pri_500: 7 (1.4%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 13/15] bpfilter: Take advantage of the facilities of struct pid X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Instead of relying on the exit_umh cleanup callback use the fact a struct pid can be tested to see if a process still exists, and that struct pid has a wait queue that notifies when the process dies. Link: https://lkml.kernel.org/r/87h7uydlu9.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/bpfilter.h | 3 ++- net/bpfilter/bpfilter_kern.c | 15 +++++---------- net/ipv4/bpfilter/sockopt.c | 15 ++++++++------- 3 files changed, 15 insertions(+), 18 deletions(-) diff --git a/include/linux/bpfilter.h b/include/linux/bpfilter.h index 4b43d2240172..8073ddce73b1 100644 --- a/include/linux/bpfilter.h +++ b/include/linux/bpfilter.h @@ -10,6 +10,8 @@ int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen); int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen); +void bpfilter_umh_cleanup(struct umd_info *info); + struct bpfilter_umh_ops { struct umd_info info; /* since ip_getsockopt() can run in parallel, serialize access to umh */ @@ -18,7 +20,6 @@ struct bpfilter_umh_ops { char __user *optval, unsigned int optlen, bool is_set); int (*start)(void); - bool stop; }; extern struct bpfilter_umh_ops bpfilter_ops; #endif diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index b73dedeb6dbf..91474884ddb7 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -18,10 +18,11 @@ static void shutdown_umh(void) struct umd_info *info = &bpfilter_ops.info; struct pid *tgid = info->tgid; - if (bpfilter_ops.stop) - return; - - kill_pid_info(SIGKILL, SEND_SIG_PRIV, tgid); + if (tgid) { + kill_pid_info(SIGKILL, SEND_SIG_PRIV, tgid); + wait_event(tgid->wait_pidfd, !pid_task(tgid, PIDTYPE_TGID)); + bpfilter_umh_cleanup(info); + } } static void __stop_umh(void) @@ -77,7 +78,6 @@ static int start_umh(void) err = fork_usermode_driver(&bpfilter_ops.info); if (err) return err; - bpfilter_ops.stop = false; pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid)); /* health check that usermode process started correctly */ @@ -100,16 +100,11 @@ static int __init load_umh(void) return err; mutex_lock(&bpfilter_ops.lock); - if (!bpfilter_ops.stop) { - err = -EFAULT; - goto out; - } err = start_umh(); if (!err && IS_ENABLED(CONFIG_INET)) { bpfilter_ops.sockopt = &__bpfilter_process_sockopt; bpfilter_ops.start = &start_umh; } -out: mutex_unlock(&bpfilter_ops.lock); if (err) umd_unload_blob(&bpfilter_ops.info); diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c index 56cbc43145f6..9455eb9cec78 100644 --- a/net/ipv4/bpfilter/sockopt.c +++ b/net/ipv4/bpfilter/sockopt.c @@ -12,16 +12,14 @@ struct bpfilter_umh_ops bpfilter_ops; EXPORT_SYMBOL_GPL(bpfilter_ops); -static void bpfilter_umh_cleanup(struct umd_info *info) +void bpfilter_umh_cleanup(struct umd_info *info) { - mutex_lock(&bpfilter_ops.lock); - bpfilter_ops.stop = true; fput(info->pipe_to_umh); fput(info->pipe_from_umh); put_pid(info->tgid); info->tgid = NULL; - mutex_unlock(&bpfilter_ops.lock); } +EXPORT_SYMBOL_GPL(bpfilter_umh_cleanup); static int bpfilter_mbox_request(struct sock *sk, int optname, char __user *optval, @@ -39,7 +37,11 @@ static int bpfilter_mbox_request(struct sock *sk, int optname, goto out; } } - if (bpfilter_ops.stop) { + if (bpfilter_ops.info.tgid && + !pid_has_task(bpfilter_ops.info.tgid, PIDTYPE_TGID)) + bpfilter_umh_cleanup(&bpfilter_ops.info); + + if (!bpfilter_ops.info.tgid) { err = bpfilter_ops.start(); if (err) goto out; @@ -70,9 +72,8 @@ int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, static int __init bpfilter_sockopt_init(void) { mutex_init(&bpfilter_ops.lock); - bpfilter_ops.stop = true; + bpfilter_ops.info.tgid = NULL; bpfilter_ops.info.driver_name = "bpfilter_umh"; - bpfilter_ops.info.cleanup = &bpfilter_umh_cleanup; return 0; } From patchwork Mon Jun 29 20:07:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632099 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4345F913 for ; Mon, 29 Jun 2020 20:12:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2F9BC20786 for ; Mon, 29 Jun 2020 20:12:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730456AbgF2UMH (ORCPT ); Mon, 29 Jun 2020 16:12:07 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:41400 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730419AbgF2UMF (ORCPT ); Mon, 29 Jun 2020 16:12:05 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq08J-0006ex-F7; Mon, 29 Jun 2020 14:12:03 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq08I-0004pf-EV; Mon, 29 Jun 2020 14:12:03 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:07:31 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87y2o53abg.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq08I-0004pf-EV;;;mid=<87y2o53abg.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX194iXzsXzdd1IVjcj63pz62HU+UBCmqU8Y= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: X-Spam-Status: No, score=-0.2 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 608 ms - load_scoreonly_sql: 0.06 (0.0%), signal_user_changed: 11 (1.8%), b_tie_ro: 9 (1.5%), parse: 1.09 (0.2%), extract_message_metadata: 15 (2.5%), get_uri_detail_list: 2.5 (0.4%), tests_pri_-1000: 23 (3.9%), tests_pri_-950: 1.24 (0.2%), tests_pri_-900: 1.06 (0.2%), tests_pri_-90: 178 (29.3%), check_bayes: 177 (29.1%), b_tokenize: 12 (2.0%), b_tok_get_all: 12 (2.0%), b_comp_prob: 3.2 (0.5%), b_tok_touch_all: 145 (23.8%), b_finish: 1.02 (0.2%), tests_pri_0: 364 (59.9%), check_dkim_signature: 0.91 (0.1%), check_dkim_adsp: 2.9 (0.5%), poll_dns_idle: 0.62 (0.1%), tests_pri_10: 2.1 (0.3%), tests_pri_500: 7 (1.2%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 14/15] umd: Remove exit_umh X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The bffilter code no longer uses the umd_info.cleanup callback. This callback is what exit_umh exists to call. So remove exit_umh and all of it's associated booking. Link: https://lkml.kernel.org/r/87bll6dlte.fsf_-_@x220.int.ebiederm.org Reviewed-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman" --- include/linux/sched.h | 1 - include/linux/umd.h | 16 ---------------- kernel/exit.c | 3 --- kernel/umd.c | 28 ---------------------------- 4 files changed, 48 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 59d1e92bb88e..edb2020875ad 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1511,7 +1511,6 @@ extern struct pid *cad_pid; #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ -#define PF_UMH 0x02000000 /* I'm an Usermodehelper process */ #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */ diff --git a/include/linux/umd.h b/include/linux/umd.h index edb1c62c62f4..71d8f4a41ad7 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -4,26 +4,10 @@ #include #include -#ifdef CONFIG_BPFILTER -void __exit_umh(struct task_struct *tsk); - -static inline void exit_umh(struct task_struct *tsk) -{ - if (unlikely(tsk->flags & PF_UMH)) - __exit_umh(tsk); -} -#else -static inline void exit_umh(struct task_struct *tsk) -{ -} -#endif - struct umd_info { const char *driver_name; struct file *pipe_to_umh; struct file *pipe_from_umh; - struct list_head list; - void (*cleanup)(struct umd_info *info); struct path wd; struct pid *tgid; }; diff --git a/kernel/exit.c b/kernel/exit.c index b53107abdd31..42f079eb71e5 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -63,7 +63,6 @@ #include #include #include -#include #include #include @@ -805,8 +804,6 @@ void __noreturn do_exit(long code) exit_task_namespaces(tsk); exit_task_work(tsk); exit_thread(tsk); - if (group_dead) - exit_umh(tsk); /* * Flush inherited counters to the parent - before the parent diff --git a/kernel/umd.c b/kernel/umd.c index c1e8eccaee76..4188b71de267 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -9,9 +9,6 @@ #include #include -static LIST_HEAD(umh_list); -static DEFINE_MUTEX(umh_list_lock); - static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *name) { struct file_system_type *type; @@ -134,7 +131,6 @@ static int umd_setup(struct subprocess_info *info, struct cred *new) umd_info->pipe_to_umh = to_umh[1]; umd_info->pipe_from_umh = from_umh[0]; umd_info->tgid = get_pid(task_tgid(current)); - current->flags |= PF_UMH; return 0; } @@ -182,11 +178,6 @@ int fork_usermode_driver(struct umd_info *info) goto out; err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); - if (!err) { - mutex_lock(&umh_list_lock); - list_add(&info->list, &umh_list); - mutex_unlock(&umh_list_lock); - } out: if (argv) argv_free(argv); @@ -194,23 +185,4 @@ int fork_usermode_driver(struct umd_info *info) } EXPORT_SYMBOL_GPL(fork_usermode_driver); -void __exit_umh(struct task_struct *tsk) -{ - struct umd_info *info; - struct pid *tgid = task_tgid(tsk); - - mutex_lock(&umh_list_lock); - list_for_each_entry(info, &umh_list, list) { - if (info->tgid == tgid) { - list_del(&info->list); - mutex_unlock(&umh_list_lock); - goto out; - } - } - mutex_unlock(&umh_list_lock); - return; -out: - if (info->cleanup) - info->cleanup(info); -} From patchwork Mon Jun 29 20:08:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11632103 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B644C913 for ; Mon, 29 Jun 2020 20:13:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A81C9206A1 for ; Mon, 29 Jun 2020 20:13:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731467AbgF2UNR (ORCPT ); Mon, 29 Jun 2020 16:13:17 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:41870 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731185AbgF2UNQ (ORCPT ); Mon, 29 Jun 2020 16:13:16 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jq09N-0006mI-1L; Mon, 29 Jun 2020 14:13:09 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jq09M-0004y7-3b; Mon, 29 Jun 2020 14:13:08 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: David Miller , Greg Kroah-Hartman , Tetsuo Handa , Alexei Starovoitov , Kees Cook , Andrew Morton , Alexei Starovoitov , Al Viro , bpf , linux-fsdevel , Daniel Borkmann , Jakub Kicinski , Masahiro Yamada , Gary Lin , Bruno Meneguele , LSM List , Casey Schaufler , Luis Chamberlain , Linus Torvalds References: <20200625095725.GA3303921@kroah.com> <778297d2-512a-8361-cf05-42d9379e6977@i-love.sakura.ne.jp> <20200625120725.GA3493334@kroah.com> <20200625.123437.2219826613137938086.davem@davemloft.net> <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> <87y2oac50p.fsf@x220.int.ebiederm.org> <87bll17ili.fsf_-_@x220.int.ebiederm.org> Date: Mon, 29 Jun 2020 15:08:36 -0500 In-Reply-To: <87bll17ili.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Mon, 29 Jun 2020 14:55:05 -0500") Message-ID: <87sged3a9n.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jq09M-0004y7-3b;;;mid=<87sged3a9n.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+cqHAFjSvF5nxXSqbZnPcbIo/0ve3+EU8= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa06.xmission.com X-Spam-Level: X-Spam-Status: No, score=-0.2 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.4996] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa06 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa06 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 558 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 10 (1.8%), b_tie_ro: 9 (1.6%), parse: 1.37 (0.2%), extract_message_metadata: 17 (3.0%), get_uri_detail_list: 1.65 (0.3%), tests_pri_-1000: 20 (3.6%), tests_pri_-950: 1.80 (0.3%), tests_pri_-900: 1.44 (0.3%), tests_pri_-90: 214 (38.4%), check_bayes: 212 (38.0%), b_tokenize: 13 (2.4%), b_tok_get_all: 8 (1.4%), b_comp_prob: 3.2 (0.6%), b_tok_touch_all: 184 (33.0%), b_finish: 1.01 (0.2%), tests_pri_0: 279 (50.0%), check_dkim_signature: 0.55 (0.1%), check_dkim_adsp: 2.2 (0.4%), poll_dns_idle: 0.58 (0.1%), tests_pri_10: 2.2 (0.4%), tests_pri_500: 6 (1.1%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 15/15] umd: Stop using split_argv X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: There is exactly one argument so there is nothing to split. All split_argv does now is cause confusion and avoid the need for a cast when passing a "const char *" string to call_usermodehelper_setup. So avoid confusion and the possibility of an odd driver name causing problems by just using a fixed argv array with a cast in the call to call_usermodehelper_setup. Signed-off-by: "Eric W. Biederman" --- kernel/umd.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/kernel/umd.c b/kernel/umd.c index 4188b71de267..ff79fb16d738 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -160,27 +160,21 @@ static void umd_cleanup(struct subprocess_info *info) int fork_usermode_driver(struct umd_info *info) { struct subprocess_info *sub_info; - char **argv = NULL; + const char *argv[] = { info->driver_name, NULL }; int err; if (WARN_ON_ONCE(info->tgid)) return -EBUSY; err = -ENOMEM; - argv = argv_split(GFP_KERNEL, info->driver_name, NULL); - if (!argv) - goto out; - - sub_info = call_usermodehelper_setup(info->driver_name, argv, NULL, - GFP_KERNEL, + sub_info = call_usermodehelper_setup(info->driver_name, + (char **)argv, NULL, GFP_KERNEL, umd_setup, umd_cleanup, info); if (!sub_info) goto out; err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); out: - if (argv) - argv_free(argv); return err; } EXPORT_SYMBOL_GPL(fork_usermode_driver);