From patchwork Fri Jun 26 12:59:57 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: 11627551 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 BE2C76C1 for ; Fri, 26 Jun 2020 13:04:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD14720836 for ; Fri, 26 Jun 2020 13:04:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727802AbgFZNE1 (ORCPT ); Fri, 26 Jun 2020 09:04:27 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:41312 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725940AbgFZNE0 (ORCPT ); Fri, 26 Jun 2020 09:04:26 -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 1joo1p-0001xN-H9; Fri, 26 Jun 2020 07:04:25 -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 1joo1o-0002IL-Hn; Fri, 26 Jun 2020 07:04:25 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds 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 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> Date: Fri, 26 Jun 2020 07:59:57 -0500 In-Reply-To: <87pn9mgfc2.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Fri, 26 Jun 2020 07:51:41 -0500") Message-ID: <87bll6dlte.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=1joo1o-0002IL-Hn;;;mid=<87bll6dlte.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/ktlOV/iIh/MDWj4PBehdloeChZvIKhmU= 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=1.3 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01,XMNoVowels 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] * 1.5 XMNoVowels Alpha-numberic number with no vowels * -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: *;Linus Torvalds X-Spam-Relay-Country: X-Spam-Timing: total 600 ms - load_scoreonly_sql: 0.04 (0.0%), signal_user_changed: 12 (2.0%), b_tie_ro: 11 (1.8%), parse: 1.03 (0.2%), extract_message_metadata: 12 (2.0%), get_uri_detail_list: 2.1 (0.3%), tests_pri_-1000: 14 (2.3%), tests_pri_-950: 1.26 (0.2%), tests_pri_-900: 1.00 (0.2%), tests_pri_-90: 189 (31.5%), check_bayes: 188 (31.3%), b_tokenize: 11 (1.9%), b_tok_get_all: 10 (1.6%), b_comp_prob: 2.8 (0.5%), b_tok_touch_all: 160 (26.7%), b_finish: 0.89 (0.1%), tests_pri_0: 358 (59.6%), check_dkim_signature: 1.06 (0.2%), check_dkim_adsp: 3.2 (0.5%), poll_dns_idle: 0.69 (0.1%), tests_pri_10: 2.4 (0.4%), tests_pri_500: 7 (1.1%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH 14/14] 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. Signed-off-by: "Eric W. Biederman" --- include/linux/sched.h | 9 --------- include/linux/umd.h | 2 -- kernel/exit.c | 2 -- kernel/umd.c | 28 ---------------------------- 4 files changed, 41 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index b62e6aaf28f0..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 */ @@ -2020,14 +2019,6 @@ 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 index 1c4579d79bce..71d8f4a41ad7 100644 --- a/include/linux/umd.h +++ b/include/linux/umd.h @@ -8,8 +8,6 @@ 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 671d5066b399..42f079eb71e5 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -804,8 +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 0db9ce3f56c9..de2f542191e5 100644 --- a/kernel/umd.c +++ b/kernel/umd.c @@ -8,9 +8,6 @@ #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; @@ -129,7 +126,6 @@ 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; } @@ -177,11 +173,6 @@ 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); @@ -189,23 +180,4 @@ 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); -}