From patchwork Tue Apr 7 00:01:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 11476985 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 E0AA892C for ; Tue, 7 Apr 2020 00:14:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B50942076E for ; Tue, 7 Apr 2020 00:14:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=yahoo.com header.i=@yahoo.com header.b="Fvccw+p+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726393AbgDGAOQ (ORCPT ); Mon, 6 Apr 2020 20:14:16 -0400 Received: from sonic311-31.consmr.mail.ne1.yahoo.com ([66.163.188.212]:43082 "EHLO sonic311-31.consmr.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726310AbgDGAOQ (ORCPT ); Mon, 6 Apr 2020 20:14:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1586218451; bh=0XcZxAeBlP/RTwdmj4dQeLeIs/fscy+Jc+4pEVr88kE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=Fvccw+p+RWkDP8uR+V1wHNIFec8l8xBRZjZ96jCqkvDHPfEF4XAsW+Pj+O2aWrDnMDA6J6VWpncKz8AolcBU4C/SJH51y3YtBAW0nvRWAh+P9JYCEwMVpdNM+CAvnipCIoE2PbMNnYPmMD3OkamN4hRiSVQnP+IM8MgY8yW0an/KS6sX9jEJXijEXYIfsy93kQad+XTxlMLhdw8NS7hTVU/81AMt6qfz+L6yixeql2XvfHuW+5Gh90TMxppUgPdlj9N94WjjhTexw/ZObE5H25QKst7VsZAA17q6MY4ER63lsPdS6prukGiE3KojIrfwrRLfux//D+bvtvjAyt7vWA== X-YMail-OSG: VGi90q0VM1micOfg.6mMiqE4ihQPHODDZAsvA6h2.6.w.6T0Gpuv3pKtGzHyA6V OeZkNMgbXd20jqAdELilB1Yfx8IWBx9Bcwkk3QQqpR_l0ZgARvuWoIGY_aGWRGNfeSnrMH2aHXsX lfRNSXt5ACvyDmtdHdrBwvFrr0sC3N4reJGQ5e4r_g7n9nNBKyPQjL9NoqGa79PFuA_A6uM0H1KR wAbcXUtBtwUpdWC3XYS6T8F9ynUyC0KGy4VBDp7_atLp8d9k8qrvzWcveQnZquVA6ww.iJ.MQAm0 5DKNWDfXKtKloKk6rVdqOYlnn.xhIHLePCGQ7Zpi9RIgPXbVDYmqRV2HXoUKSUZxQhuUc0h8Lhnp LPZF2GIf20Asxtvw4O43mhvGTGZBAb.WJm4hjgMh5xAIjaFI7DsW02t3O68EwKkv_Az4wYJbS8lO A97T7158H7ifVYck93PX8Y1g7mzC7vMGsIwbRvu5rKQCaNEkcGsQi1kScnIny..Hmz0_hExmn2Bh QBf2JV495z8sZntRsoOq.j2GzrJ9E5S0bOugVyI16j7uIqrxnnnG0MMxK5k3s4ExL3Gh7xy7WsFS myVYr7Gim.C7CaCPI0kw0smqQyDByMScBepSwPkcEqI6N9uzMnUadAQlggKtzkUAwC4.KfqjGbL. ZL7ocnB72VNIcEwJAe2Aq1qXX8Le_85k6kXhG5Rltcieeoq6p7iQjPBt3Jr3RVKRv_qm8_I_Zd3b Qz8EykxS.TmW9Ykto.I4SgFEQYiaSo4D1mus6rqbD85nHriI7ZGRCKMvx2MXs9.ZcQJ4g33sphPf 2JYYyc_I6sMUKUiYqw0.5tn7Wx536CWFX_9SHkd48hgkHlySe1AYX96nbbCpwhOwP88O.ATu2tnU W15EX7aoSyTWLBEC5hkc5bhtxSIEcY88naZomCMTLz5SMzua6P4jQoiICGpQAT2BjhtPBSg83vH4 Q_clgElF_9769gJyKXwDzxS44BB9bIJVdcx2sEL8pNvMuoKsK_HD3NujBwNvijcUQ7AOSx2E3edI 4fdAsSZnawlOFH_gH2F.Eq4EW1MULPK7Zj6.y8T_vGipMM7KDezJXxITgeZAOXxjgH.NwlRYUff7 Fn3KMn.BR04Xy6wIarVn1PcksWiUFrxY9QhjTx01LJKOcjUt.Kbs31Fd3FP0OBtIY9JoTSX5tbU5 JWhC8wlF1B35CfLmctm4N6CY27Z1QyP5Ukru8DK_CAiIV9jlntUd8Atg6o49DiwnYH4n0FjwLuM5 vVMs2r6p4dFNq3.yOo1AA4uX45ljUx.WBH5WVluXzELuPADso52r_7dq4d0cfPWAHJd0SnSBi944 QR7_mInrrHMRZbUTGKp8IQeZXJ9nJuqUOh2HUPt7..6UCelRG2m_sW8U_8DICGzf9V5kXgiteJZA Ce3Hf1i7lb8szQXogY3j9LWoC.ZWfqYuskdE_nir91SvHwlJWpHeupJb.mYL0gfJ3fPBf Received: from sonic.gate.mail.ne1.yahoo.com by sonic311.consmr.mail.ne1.yahoo.com with HTTP; Tue, 7 Apr 2020 00:14:11 +0000 Received: by smtp428.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID 038375d5a065d4eefc04c4e3ebffc1f9; Tue, 07 Apr 2020 00:14:07 +0000 (UTC) From: Casey Schaufler To: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Cc: casey@schaufler-ca.com, keescook@chromium.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, sds@tycho.nsa.gov, linux-audit@redhat.com Subject: [PATCH v16 11/23] LSM: Use lsmblob in security_cred_getsecid Date: Mon, 6 Apr 2020 17:01:47 -0700 Message-Id: <20200407000159.43602-12-casey@schaufler-ca.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200407000159.43602-1-casey@schaufler-ca.com> References: <20200407000159.43602-1-casey@schaufler-ca.com> MIME-Version: 1.0 Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org Change the security_cred_getsecid() interface to fill in a lsmblob instead of a u32 secid. The associated data elements in the audit sub-system are changed from a secid to a lsmblob to accommodate multiple possible LSM audit users. Reviewed-by: Kees Cook Reviewed-by: John Johansen Acked-by: Stephen Smalley Acked-by: Paul Moore Signed-off-by: Casey Schaufler cc: linux-integrity@vger.kernel.org --- include/linux/security.h | 2 +- kernel/audit.c | 25 +++++++---------------- kernel/audit.h | 5 +++-- kernel/auditsc.c | 33 +++++++++++-------------------- security/integrity/ima/ima_main.c | 8 ++++---- security/security.c | 12 ++++++++--- 6 files changed, 36 insertions(+), 49 deletions(-) diff --git a/include/linux/security.h b/include/linux/security.h index 3f07ba240ec5..9b4705d4ec2c 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -459,7 +459,7 @@ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp); void security_cred_free(struct cred *cred); int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp); void security_transfer_creds(struct cred *new, const struct cred *old); -void security_cred_getsecid(const struct cred *c, u32 *secid); +void security_cred_getsecid(const struct cred *c, struct lsmblob *blob); int security_kernel_act_as(struct cred *new, struct lsmblob *blob); int security_kernel_create_files_as(struct cred *new, struct inode *inode); int security_kernel_module_request(char *kmod_name); diff --git a/kernel/audit.c b/kernel/audit.c index 1a7646854813..a7430f09afd9 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -125,7 +125,7 @@ static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME; /* The identity of the user shutting down the audit system. */ kuid_t audit_sig_uid = INVALID_UID; pid_t audit_sig_pid = -1; -u32 audit_sig_sid = 0; +struct lsmblob audit_sig_lsm; /* Records can be lost in several ways: 0) [suppressed in audit_alloc] @@ -1419,29 +1419,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) } case AUDIT_SIGNAL_INFO: len = 0; - if (audit_sig_sid) { - struct lsmblob blob; - - /* - * lsmblob_init sets all values in the lsmblob - * to audit_sig_sid. This is temporary until - * audit_sig_sid is converted to a lsmblob, which - * happens later in this patch set. - */ - lsmblob_init(&blob, audit_sig_sid); - err = security_secid_to_secctx(&blob, &ctx, &len); + if (lsmblob_is_set(&audit_sig_lsm)) { + err = security_secid_to_secctx(&audit_sig_lsm, &ctx, + &len); if (err) return err; } sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL); if (!sig_data) { - if (audit_sig_sid) + if (lsmblob_is_set(&audit_sig_lsm)) security_release_secctx(ctx, len); return -ENOMEM; } sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid); sig_data->pid = audit_sig_pid; - if (audit_sig_sid) { + if (lsmblob_is_set(&audit_sig_lsm)) { memcpy(sig_data->ctx, ctx, len); security_release_secctx(ctx, len); } @@ -2284,7 +2276,6 @@ int audit_set_loginuid(kuid_t loginuid) int audit_signal_info(int sig, struct task_struct *t) { kuid_t uid = current_uid(), auid; - struct lsmblob blob; if (auditd_test_task(t) && (sig == SIGTERM || sig == SIGHUP || @@ -2295,9 +2286,7 @@ int audit_signal_info(int sig, struct task_struct *t) audit_sig_uid = auid; else audit_sig_uid = uid; - security_task_getsecid(current, &blob); - /* scaffolding until audit_sig_sid is converted */ - audit_sig_sid = blob.secid[0]; + security_task_getsecid(current, &audit_sig_lsm); } return audit_signal_info_syscall(t); diff --git a/kernel/audit.h b/kernel/audit.h index 6fb7160412d4..f65f516913c6 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -134,7 +135,7 @@ struct audit_context { kuid_t target_auid; kuid_t target_uid; unsigned int target_sessionid; - u32 target_sid; + struct lsmblob target_lsm; char target_comm[TASK_COMM_LEN]; struct audit_tree_refs *trees, *first_trees; @@ -329,7 +330,7 @@ extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len); extern pid_t audit_sig_pid; extern kuid_t audit_sig_uid; -extern u32 audit_sig_sid; +extern struct lsmblob audit_sig_lsm; extern int audit_filter(int msgtype, unsigned int listtype); diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 5d4ce44bff91..97da8bf2eda9 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -112,7 +112,7 @@ struct audit_aux_data_pids { kuid_t target_auid[AUDIT_AUX_PIDS]; kuid_t target_uid[AUDIT_AUX_PIDS]; unsigned int target_sessionid[AUDIT_AUX_PIDS]; - u32 target_sid[AUDIT_AUX_PIDS]; + struct lsmblob target_lsm[AUDIT_AUX_PIDS]; char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; int pid_count; }; @@ -964,14 +964,14 @@ static inline void audit_free_context(struct audit_context *context) } static int audit_log_pid_context(struct audit_context *context, pid_t pid, - kuid_t auid, kuid_t uid, unsigned int sessionid, - u32 sid, char *comm) + kuid_t auid, kuid_t uid, + unsigned int sessionid, + struct lsmblob *blob, char *comm) { struct audit_buffer *ab; char *ctx = NULL; u32 len; int rc = 0; - struct lsmblob blob; ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); if (!ab) @@ -980,9 +980,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid, audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, from_kuid(&init_user_ns, auid), from_kuid(&init_user_ns, uid), sessionid); - if (sid) { - lsmblob_init(&blob, sid); - if (security_secid_to_secctx(&blob, &ctx, &len)) { + if (lsmblob_is_set(blob)) { + if (security_secid_to_secctx(blob, &ctx, &len)) { audit_log_format(ab, " obj=(none)"); rc = 1; } else { @@ -1553,7 +1552,7 @@ static void audit_log_exit(void) axs->target_auid[i], axs->target_uid[i], axs->target_sessionid[i], - axs->target_sid[i], + &axs->target_lsm[i], axs->target_comm[i])) call_panic = 1; } @@ -1562,7 +1561,7 @@ static void audit_log_exit(void) audit_log_pid_context(context, context->target_pid, context->target_auid, context->target_uid, context->target_sessionid, - context->target_sid, context->target_comm)) + &context->target_lsm, context->target_comm)) call_panic = 1; if (context->pwd.dentry && context->pwd.mnt) { @@ -1740,7 +1739,7 @@ void __audit_syscall_exit(int success, long return_code) context->aux = NULL; context->aux_pids = NULL; context->target_pid = 0; - context->target_sid = 0; + lsmblob_init(&context->target_lsm, 0); context->sockaddr_len = 0; context->type = 0; context->fds[0] = -1; @@ -2393,15 +2392,12 @@ int __audit_sockaddr(int len, void *a) void __audit_ptrace(struct task_struct *t) { struct audit_context *context = audit_context(); - struct lsmblob blob; context->target_pid = task_tgid_nr(t); context->target_auid = audit_get_loginuid(t); context->target_uid = task_uid(t); context->target_sessionid = audit_get_sessionid(t); - security_task_getsecid(t, &blob); - /* scaffolding - until target_sid is converted */ - context->target_sid = blob.secid[0]; + security_task_getsecid(t, &context->target_lsm); memcpy(context->target_comm, t->comm, TASK_COMM_LEN); } @@ -2417,7 +2413,6 @@ int audit_signal_info_syscall(struct task_struct *t) struct audit_aux_data_pids *axp; struct audit_context *ctx = audit_context(); kuid_t t_uid = task_uid(t); - struct lsmblob blob; if (!audit_signals || audit_dummy_context()) return 0; @@ -2429,9 +2424,7 @@ int audit_signal_info_syscall(struct task_struct *t) ctx->target_auid = audit_get_loginuid(t); ctx->target_uid = t_uid; ctx->target_sessionid = audit_get_sessionid(t); - security_task_getsecid(t, &blob); - /* scaffolding until target_sid is converted */ - ctx->target_sid = blob.secid[0]; + security_task_getsecid(t, &ctx->target_lsm); memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); return 0; } @@ -2452,9 +2445,7 @@ int audit_signal_info_syscall(struct task_struct *t) axp->target_auid[axp->pid_count] = audit_get_loginuid(t); axp->target_uid[axp->pid_count] = t_uid; axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); - security_task_getsecid(t, &blob); - /* scaffolding until target_sid is converted */ - axp->target_sid[axp->pid_count] = blob.secid[0]; + security_task_getsecid(t, &axp->target_lsm[axp->pid_count]); memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); axp->pid_count++; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 1f50f68a6f5b..8ad399ea7883 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -412,7 +412,6 @@ int ima_file_mmap(struct file *file, unsigned long prot) int ima_bprm_check(struct linux_binprm *bprm) { int ret; - u32 secid; struct lsmblob blob; security_task_getsecid(current, &blob); @@ -422,9 +421,10 @@ int ima_bprm_check(struct linux_binprm *bprm) if (ret) return ret; - security_cred_getsecid(bprm->cred, &secid); - return process_measurement(bprm->file, bprm->cred, secid, NULL, 0, - MAY_EXEC, CREDS_CHECK); + security_cred_getsecid(bprm->cred, &blob); + /* scaffolding until process_measurement changes */ + return process_measurement(bprm->file, bprm->cred, blob.secid[0], + NULL, 0, MAY_EXEC, CREDS_CHECK); } /** diff --git a/security/security.c b/security/security.c index 8cced3fc9ad3..bf71066ea19b 100644 --- a/security/security.c +++ b/security/security.c @@ -1647,10 +1647,16 @@ void security_transfer_creds(struct cred *new, const struct cred *old) call_void_hook(cred_transfer, new, old); } -void security_cred_getsecid(const struct cred *c, u32 *secid) +void security_cred_getsecid(const struct cred *c, struct lsmblob *blob) { - *secid = 0; - call_void_hook(cred_getsecid, c, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]); + } } EXPORT_SYMBOL(security_cred_getsecid);