From patchwork Thu Apr 7 21:22:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 12805762 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B35BC433EF for ; Thu, 7 Apr 2022 21:29:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231488AbiDGVb3 (ORCPT ); Thu, 7 Apr 2022 17:31:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231487AbiDGVbX (ORCPT ); Thu, 7 Apr 2022 17:31:23 -0400 Received: from sonic305-28.consmr.mail.ne1.yahoo.com (sonic305-28.consmr.mail.ne1.yahoo.com [66.163.185.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 457891A54C2 for ; Thu, 7 Apr 2022 14:29:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1649366960; bh=qWirYQox07XOTVDcUrrg8xs3C9TRpx0QbTKULbb9FEM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject:Reply-To; b=IAF16EcNdlSIFBD0a0VK/1ymoQOmKb9URDU8BkgrcR/Ko4hnibylkHT/bXv6Xuhb/szD+/Akm7f7ZFXuK7qaAiYP3K77/IzziyzxVRuN2Bn68MIVImAaHQr+QmN1FPhkS/ktZB4sS+Ctk8LeyHv7C3bN/R2D2FDV1nCpjlkJCsaZge/AYUusCbVXwRok4WOygN0Cl8JUtGaw04fSN+FodAvoiZ/3FA3ikgYT678rMhx9mUtr2I5yXo4PVRCFMWROOkhdBFKCJvSOCwhbem+cmZMjAPFcQhfg67OR/Eqmy33rcQMG1+47voY7qP9GVtBa5ZSXRBP+NvvlHYaXtD5P3g== X-SONIC-DKIM-SIGN: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1649366960; bh=rEAXI7AMm25t5WclhriyAb/Mh6Ol6RVrJuhb3efFEMP=; h=X-Sonic-MF:From:To:Subject:Date:From:Subject; b=twgrKphKQpUxqBkjc8KhGRV7qUttnhomDby8UeZHbD0Of2ulnlde56fWYxOBqOFtU8FDi16XVdJWFOa/CO5qEmnKwiEUc9nK54xDNryvjJtD7lrm6M9QEQI0KjkPwPlrdvLVmTGv7BkkZL2Pyt2lN+RiKqS0iTvN4QbAu25a58N8cysyBCl72RPWpu6or2mSyXdSBuE5gNIMHBDwqjiMXyHpRDIBOnaTAdCUTukLrgYX9mK0JWctYe+iB26qHbkLCYEk6Lnh0yU8fxbYKjnp6mEmUQXbC4D4z5fxL7Bw04dEssfo3eX8FmaCR7IpWyV1FXjfZqrF7XD31Uv5xDBkHg== X-YMail-OSG: ZsNQIIoVM1m_ycDgIkAOSpRO3H0hEilZ1AvtLLr4IqmJ_PfQVAOJuWS3MTNGCns zlrbtJe8vD4nkdUqhqVJMaHQb.I80I6eJ0keBb8SnrS53i3r9OLI5573npyAqPGyTasNEHEUCIa9 hvQ6Mjh68c9X67D6Lw99yEgPfGc.eldZNwMnpI1cgN0LHkE77L6nwjPU0ucXYaK5rTMpvRdGOqAR PSQxu0eaEJhT6BcyW.JeFdhxlo59gLu7Yr3jWEm5pboO_odmn5jGHduLj3MsZBAipbwelosX.4v9 ojo9ZFkGLqZ1DoUGwWtFSkCj7DvmCKaGjTRJJdX96sEhJYgVtwdZlUKKbyA4jcigBehhRZWQcH_d vWJkMbPAPcl6FFAgupdr5VsnAx04U6fImbUlOHg8LhjPvWqcNTjfjQ.F8ZQI8pFNuAp36ddbZJuN ehvM16Y5lp1DiXhE.FxR.VVQpv.UMA2QUzEABWWO9cUcIo5q40YGQlGzYVulkeciSg6wKcpePrqX LW2QAYJ5ZSqMLoGz5x.hJg2la_kC8andKodLcqHsdqm7znQ7.wJiekxWlE2b1LwzGTr5bRzog_Hf dtuQUCdXlKOgv_Exb_n5RzGdtC4mJ4BhQAtuxEPHXframvwZCXzueDv0Trx5M6nMExa6Jr.xklFL 2Gz5.GEiQ2AMeo_dbDphxC.mSQjQAcrI3nG.jlJ7gkOI.J_iSkjuW.i6zkbdcRVjwqPXnW3kHz8s EeI0AW3zb_duHUHXLNUJ1pEBMHBcX3GPzA3zA5eMN2N1yjViTFvHzAvy8ixzTJ2Dpq2zGxZ5V4MV JunOZK5tZfr_4XExDzJUEFvFsJ4jDQzS2WbngirywfsCkq7AiSpOI.m8eB_fwR8JKFDlwTxXn5Tl 1cGyeNDoJKGrSfwwAf.sdFhVGSBRqHF9OEwrNyOVcIn2BU3RmgpOlflisrAvjT2S8Seyq0WZXcU5 Kli9N5HRg7dadQnv8.NQSYkhwQo3rT9Ajf22OG0V3_irz9Dj_cIHJP9iJk1zv6ErLbVUm4y28Go_ H0q3LwBCqfKSRNuLuWA2.JVxzg4sAJ9AxxnAMqi5EVpQETPMyo5Qb0YieLBvlRvMv6z9LdWlQW8e Y.Lqe.53Zk6FcnXOjkwZUwgfpsuRlhezO5lpX_MhxUf26LjDoD6Jj.jxxHhLthXURgS0DTSfjvo8 ICBimp8yVeJvjktGRHqq.ZW6.eYePmsleGNKc00GH_jwjuWHXrBMSn2fZFiUvDQHxyutw5JUpXqP jTE1Z7HOodbBa.1A2T7jCvKo0ev6oQdLYo5Fb6FmO6H9REgSQG2YI18Ib56JwaE.3g8X8YOLCe_u ZvmAe045DXdatht6ShJqak0L.cfJieALvpRowDv3iXWx.rXFAM8rK8CcWsEFCyWMB78h7hUYAI.a slreO2yjiQNBwIS2aNnk0Kl0d5klZzjRSIhKFufXLuFihXgbAVRsYXnEOrwBm4.6S0asq418eRH8 wfXyEJI2t30TFdi3xWnnfhT8I10PE8Fzxt5G.Hub8U44Ied4EO1abMFk66EIDvLMfpQCAqyCI9.v 5uPchEnOkYDNkMfTYnyFG0F_lEjxv6q9G79EMY4fS778rNB6gr1HY9j85GghXeC1i4NYe1741zRz 6a.V3z3W.1PeLqFTjfZzpCZXn65pKwpp7q87LAAWAPV._nJADWexr02gnmthkZvIjp2oQXPyiepZ ehT7p3QosKH17u3Pei.YBa3OjQgV7c57A5Uol5QJK3A9lYp1rVPJv6LJgM3eXC9sfxCVs7mcZf5o COSMKxIBYCUsc9tOrsCcVcpqFjzL1Y4MhOpR2.czHNP7hOC3Bn_IUxRlXUwpUNWhVC8EdHUDWMND MQgKSPtC1NvijHQaq4IbzfQvr936seImQI2ehQR9GAsMz4Iyd3GssAtK3Gv.bj7MvIVJKzGtYzWz W4I.oAC.VTQxyl_vCfIuPRzmDiFv2hUWVDd.pdVn3j70cx7aDoJ0rsUoKg__Q15Mqp54OcbQ32_O LccH_e_gqcYneeUNpp7YXINCR4zedYVkhlqap098LFquF.sii0GQDkeGuzJKmoB0kg118XpKBNqu RswGWBet1Nn5TQnKea3l5AsaN2ZVrydvW_R1UrRtOd6ut6hd80QMdSHCOwyv0vTBp_XdGqY0ZnmL g3cAr_JmZnt8s2xHgNCh_ALZEtqiSsBj8EgE4z57CLj3JxiTyqP4zov4akNdj3.l1waFpjveeDRl kl6syn_pLXH84x_2noM.KGpx.AzMMTeKQt3q7yETCPt3zzRgnVi8ZTAJWL5O9w.STSx6R7hnQ39. HkHJrsUfGxtEtyNyo5YxU9sMI2Q8XJYkvFGtAKZG.Gw-- X-Sonic-MF: Received: from sonic.gate.mail.ne1.yahoo.com by sonic305.consmr.mail.ne1.yahoo.com with HTTP; Thu, 7 Apr 2022 21:29:20 +0000 Received: by kubenode520.mail-prod1.omega.ne1.yahoo.com (VZM Hermes SMTP Server) with ESMTPA ID 5dcb49a390aaddbe04fc320d63f58082; Thu, 07 Apr 2022 21:29:18 +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, linux-audit@redhat.com, keescook@chromium.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, stephen.smalley.work@gmail.com, linux-kernel@vger.kernel.org, Greg Kroah-Hartman , linux-api@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH v34 14/29] LSM: Specify which LSM to display Date: Thu, 7 Apr 2022 14:22:15 -0700 Message-Id: <20220407212230.12893-15-casey@schaufler-ca.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220407212230.12893-1-casey@schaufler-ca.com> References: <20220407212230.12893-1-casey@schaufler-ca.com> MIME-Version: 1.0 Precedence: bulk List-ID: Create a new entry "interface_lsm" in the procfs attr directory for controlling which LSM security information is displayed for a process. A process can only read or write its own display value. The name of an active LSM that supplies hooks for human readable data may be written to "interface_lsm" to set the value. The name of the LSM currently in use can be read from "interface_lsm". At this point there can only be one LSM capable of display active. A helper function lsm_task_ilsm() is provided to get the interface lsm slot for a task_struct. Setting the "interface_lsm" requires that all security modules using setprocattr hooks allow the action. Each security module is responsible for defining its policy. AppArmor hook provided by John Johansen SELinux hook provided by Stephen Smalley Signed-off-by: Casey Schaufler Cc: Kees Cook Cc: Stephen Smalley Cc: Paul Moore Cc: John Johansen Cc: Greg Kroah-Hartman Cc: linux-api@vger.kernel.org Cc: linux-doc@vger.kernel.org --- .../ABI/testing/procfs-attr-lsm_display | 22 +++ Documentation/security/lsm.rst | 14 ++ fs/proc/base.c | 1 + include/linux/security.h | 17 ++ security/apparmor/include/apparmor.h | 3 +- security/apparmor/lsm.c | 32 ++++ security/security.c | 166 ++++++++++++++++-- security/selinux/hooks.c | 11 ++ security/selinux/include/classmap.h | 3 +- security/smack/smack_lsm.c | 7 + 10 files changed, 257 insertions(+), 19 deletions(-) create mode 100644 Documentation/ABI/testing/procfs-attr-lsm_display diff --git a/Documentation/ABI/testing/procfs-attr-lsm_display b/Documentation/ABI/testing/procfs-attr-lsm_display new file mode 100644 index 000000000000..0f60005c235c --- /dev/null +++ b/Documentation/ABI/testing/procfs-attr-lsm_display @@ -0,0 +1,22 @@ +What: /proc/*/attr/lsm_display +Contact: linux-security-module@vger.kernel.org, +Description: The name of the Linux security module (LSM) that will + provide information in the /proc/*/attr/current, + /proc/*/attr/prev and /proc/*/attr/exec interfaces. + The details of permissions required to read from + this interface are dependent on the LSMs active on the + system. + A process cannot write to this interface unless it + refers to itself. + The other details of permissions required to write to + this interface are dependent on the LSMs active on the + system. + The format of the data used by this interface is a + text string identifying the name of an LSM. The values + accepted are: + selinux - the SELinux LSM + smack - the Smack LSM + apparmor - The AppArmor LSM + By convention the LSM names are lower case and do not + contain special characters. +Users: LSM user-space diff --git a/Documentation/security/lsm.rst b/Documentation/security/lsm.rst index 6a2a2e973080..b77b4a540391 100644 --- a/Documentation/security/lsm.rst +++ b/Documentation/security/lsm.rst @@ -129,3 +129,17 @@ to identify it as the first security module to be registered. The capabilities security module does not use the general security blobs, unlike other modules. The reasons are historical and are based on overhead, complexity and performance concerns. + +LSM External Interfaces +======================= + +The LSM infrastructure does not generally provide external interfaces. +The individual security modules provide what external interfaces they +require. + +The file ``/sys/kernel/security/lsm`` provides a comma +separated list of the active security modules. + +The file ``/proc/pid/attr/interface_lsm`` contains the name of the security +module for which the ``/proc/pid/attr/current`` interface will +apply. This interface can be written to. diff --git a/fs/proc/base.c b/fs/proc/base.c index c1031843cc6a..f2d15348bdff 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2827,6 +2827,7 @@ static const struct pid_entry attr_dir_stuff[] = { ATTR(NULL, "fscreate", 0666), ATTR(NULL, "keycreate", 0666), ATTR(NULL, "sockcreate", 0666), + ATTR(NULL, "interface_lsm", 0666), #ifdef CONFIG_SECURITY_SMACK DIR("smack", 0555, proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops), diff --git a/include/linux/security.h b/include/linux/security.h index e36d7f35b228..4a4abda5d06d 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -220,6 +220,23 @@ static inline u32 lsmblob_value(const struct lsmblob *blob) return 0; } +/** + * lsm_task_ilsm - the "interface_lsm" for this task + * @task: The task to report on + * + * Returns the task's interface LSM slot. + */ +static inline int lsm_task_ilsm(struct task_struct *task) +{ +#ifdef CONFIG_SECURITY + int *ilsm = task->security; + + if (ilsm) + return *ilsm; +#endif + return LSMBLOB_INVALID; +} + /* These functions are in security/commoncap.c */ extern int cap_capable(const struct cred *cred, struct user_namespace *ns, int cap, unsigned int opts); diff --git a/security/apparmor/include/apparmor.h b/security/apparmor/include/apparmor.h index 1fbabdb565a8..b1622fcb4394 100644 --- a/security/apparmor/include/apparmor.h +++ b/security/apparmor/include/apparmor.h @@ -28,8 +28,9 @@ #define AA_CLASS_SIGNAL 10 #define AA_CLASS_NET 14 #define AA_CLASS_LABEL 16 +#define AA_CLASS_DISPLAY_LSM 17 -#define AA_CLASS_LAST AA_CLASS_LABEL +#define AA_CLASS_LAST AA_CLASS_DISPLAY_LSM /* Control parameters settable through module/boot flags */ extern enum audit_mode aa_g_audit; diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 1e53fea61335..29181bc8c693 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -621,6 +621,25 @@ static int apparmor_getprocattr(struct task_struct *task, char *name, return error; } + +static int profile_interface_lsm(struct aa_profile *profile, + struct common_audit_data *sa) +{ + struct aa_perms perms = { }; + unsigned int state; + + state = PROFILE_MEDIATES(profile, AA_CLASS_DISPLAY_LSM); + if (state) { + aa_compute_perms(profile->policy.dfa, state, &perms); + aa_apply_modes_to_perms(profile, &perms); + aad(sa)->label = &profile->label; + + return aa_check_perms(profile, &perms, AA_MAY_WRITE, sa, NULL); + } + + return 0; +} + static int apparmor_setprocattr(const char *name, void *value, size_t size) { @@ -632,6 +651,19 @@ static int apparmor_setprocattr(const char *name, void *value, if (size == 0) return -EINVAL; + /* LSM infrastructure does actual setting of interface_lsm if allowed */ + if (!strcmp(name, "interface_lsm")) { + struct aa_profile *profile; + struct aa_label *label; + + aad(&sa)->info = "set interface lsm"; + label = begin_current_label_crit_section(); + error = fn_for_each_confined(label, profile, + profile_interface_lsm(profile, &sa)); + end_current_label_crit_section(label); + return error; + } + /* AppArmor requires that the buffer must be null terminated atm */ if (args[size - 1] != '\0') { /* null terminate */ diff --git a/security/security.c b/security/security.c index 2ad0d4eb24b3..52d3d0601636 100644 --- a/security/security.c +++ b/security/security.c @@ -78,7 +78,16 @@ static struct kmem_cache *lsm_file_cache; static struct kmem_cache *lsm_inode_cache; char *lsm_names; -static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init; + +/* + * The task blob includes the "interface_lsm" slot used for + * chosing which module presents contexts. + * Using a long to avoid potential alignment issues with + * module assigned task blobs. + */ +static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init = { + .lbs_task = sizeof(long), +}; /* Boot-time LSM user choice */ static __initdata const char *chosen_lsm_order; @@ -672,6 +681,8 @@ int lsm_inode_alloc(struct inode *inode) */ static int lsm_task_alloc(struct task_struct *task) { + int *ilsm; + if (blob_sizes.lbs_task == 0) { task->security = NULL; return 0; @@ -680,6 +691,15 @@ static int lsm_task_alloc(struct task_struct *task) task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL); if (task->security == NULL) return -ENOMEM; + + /* + * The start of the task blob contains the "interface" LSM slot number. + * Start with it set to the invalid slot number, indicating that the + * default first registered LSM be displayed. + */ + ilsm = task->security; + *ilsm = LSMBLOB_INVALID; + return 0; } @@ -1752,14 +1772,26 @@ int security_file_open(struct file *file) int security_task_alloc(struct task_struct *task, unsigned long clone_flags) { + int *oilsm = current->security; + int *nilsm; int rc = lsm_task_alloc(task); - if (rc) + if (unlikely(rc)) return rc; + rc = call_int_hook(task_alloc, 0, task, clone_flags); - if (unlikely(rc)) + if (unlikely(rc)) { security_task_free(task); - return rc; + return rc; + } + + if (oilsm) { + nilsm = task->security; + if (nilsm) + *nilsm = *oilsm; + } + + return 0; } void security_task_free(struct task_struct *task) @@ -2191,23 +2223,110 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name, char **value) { struct security_hook_list *hp; + int ilsm = lsm_task_ilsm(current); + int slot = 0; + + if (!strcmp(name, "interface_lsm")) { + /* + * lsm_slot will be 0 if there are no displaying modules. + */ + if (lsm_slot == 0) + return -EINVAL; + + /* + * Only allow getting the current process' interface_lsm. + * There are too few reasons to get another process' + * interface_lsm and too many LSM policy issues. + */ + if (current != p) + return -EINVAL; + + ilsm = lsm_task_ilsm(p); + if (ilsm != LSMBLOB_INVALID) + slot = ilsm; + *value = kstrdup(lsm_slotlist[slot]->lsm, GFP_KERNEL); + if (*value) + return strlen(*value); + return -ENOMEM; + } hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) { if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) continue; + if (lsm == NULL && ilsm != LSMBLOB_INVALID && + ilsm != hp->lsmid->slot) + continue; return hp->hook.getprocattr(p, name, value); } return LSM_RET_DEFAULT(getprocattr); } +/** + * security_setprocattr - Set process attributes via /proc + * @lsm: name of module involved, or NULL + * @name: name of the attribute + * @value: value to set the attribute to + * @size: size of the value + * + * Set the process attribute for the specified security module + * to the specified value. Note that this can only be used to set + * the process attributes for the current, or "self" process. + * The /proc code has already done this check. + * + * Returns 0 on success, an appropriate code otherwise. + */ int security_setprocattr(const char *lsm, const char *name, void *value, size_t size) { struct security_hook_list *hp; + char *termed; + char *copy; + int *ilsm = current->security; + int rc = -EINVAL; + int slot = 0; + + if (!strcmp(name, "interface_lsm")) { + /* + * Change the "interface_lsm" value only if all the security + * modules that support setting a procattr allow it. + * It is assumed that all such security modules will be + * cooperative. + */ + if (size == 0) + return -EINVAL; + + hlist_for_each_entry(hp, &security_hook_heads.setprocattr, + list) { + rc = hp->hook.setprocattr(name, value, size); + if (rc < 0) + return rc; + } + + rc = -EINVAL; + + copy = kmemdup_nul(value, size, GFP_KERNEL); + if (copy == NULL) + return -ENOMEM; + + termed = strsep(©, " \n"); + + for (slot = 0; slot < lsm_slot; slot++) + if (!strcmp(termed, lsm_slotlist[slot]->lsm)) { + *ilsm = lsm_slotlist[slot]->slot; + rc = size; + break; + } + + kfree(termed); + return rc; + } hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) { if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) continue; + if (lsm == NULL && *ilsm != LSMBLOB_INVALID && + *ilsm != hp->lsmid->slot) + continue; return hp->hook.setprocattr(name, value, size); } return LSM_RET_DEFAULT(setprocattr); @@ -2227,15 +2346,15 @@ EXPORT_SYMBOL(security_ismaclabel); int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen) { struct security_hook_list *hp; - int rc; + int ilsm = lsm_task_ilsm(current); hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) { if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) continue; - rc = hp->hook.secid_to_secctx(blob->secid[hp->lsmid->slot], - secdata, seclen); - if (rc != LSM_RET_DEFAULT(secid_to_secctx)) - return rc; + if (ilsm == LSMBLOB_INVALID || ilsm == hp->lsmid->slot) + return hp->hook.secid_to_secctx( + blob->secid[hp->lsmid->slot], + secdata, seclen); } return LSM_RET_DEFAULT(secid_to_secctx); @@ -2246,16 +2365,15 @@ int security_secctx_to_secid(const char *secdata, u32 seclen, struct lsmblob *blob) { struct security_hook_list *hp; - int rc; + int ilsm = lsm_task_ilsm(current); lsmblob_init(blob, 0); hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) { if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) continue; - rc = hp->hook.secctx_to_secid(secdata, seclen, - &blob->secid[hp->lsmid->slot]); - if (rc != 0) - return rc; + if (ilsm == LSMBLOB_INVALID || ilsm == hp->lsmid->slot) + return hp->hook.secctx_to_secid(secdata, seclen, + &blob->secid[hp->lsmid->slot]); } return 0; } @@ -2263,7 +2381,14 @@ EXPORT_SYMBOL(security_secctx_to_secid); void security_release_secctx(char *secdata, u32 seclen) { - call_void_hook(release_secctx, secdata, seclen); + struct security_hook_list *hp; + int ilsm = lsm_task_ilsm(current); + + hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list) + if (ilsm == LSMBLOB_INVALID || ilsm == hp->lsmid->slot) { + hp->hook.release_secctx(secdata, seclen); + return; + } } EXPORT_SYMBOL(security_release_secctx); @@ -2404,8 +2529,15 @@ EXPORT_SYMBOL(security_sock_rcv_skb); int security_socket_getpeersec_stream(struct socket *sock, char __user *optval, int __user *optlen, unsigned len) { - return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock, - optval, optlen, len); + int ilsm = lsm_task_ilsm(current); + struct security_hook_list *hp; + + hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream, + list) + if (ilsm == LSMBLOB_INVALID || ilsm == hp->lsmid->slot) + return hp->hook.socket_getpeersec_stream(sock, optval, + optlen, len); + return -ENOPROTOOPT; } int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9f82920ca986..bf93dc6ad160 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6388,6 +6388,17 @@ static int selinux_setprocattr(const char *name, void *value, size_t size) /* * Basic control over ability to set these attributes at all. */ + + /* + * For setting interface_lsm, we only perform a permission check; + * the actual update to the interface_lsm value is handled by the + * LSM framework. + */ + if (!strcmp(name, "interface_lsm")) + return avc_has_perm(&selinux_state, + mysid, mysid, SECCLASS_PROCESS2, + PROCESS2__SETINTERFACE_LSM, NULL); + if (!strcmp(name, "exec")) error = avc_has_perm(&selinux_state, mysid, mysid, SECCLASS_PROCESS, diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h index 35aac62a662e..79b480983bdc 100644 --- a/security/selinux/include/classmap.h +++ b/security/selinux/include/classmap.h @@ -53,7 +53,8 @@ struct security_class_mapping secclass_map[] = { "execmem", "execstack", "execheap", "setkeycreate", "setsockcreate", "getrlimit", NULL } }, { "process2", - { "nnp_transition", "nosuid_transition", NULL } }, + { "nnp_transition", "nosuid_transition", "setinterface_lsm", + NULL } }, { "system", { "ipc_info", "syslog_read", "syslog_mod", "syslog_console", "module_request", "module_load", NULL } }, diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 6e0eaecd8256..552c4d4d8fac 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3516,6 +3516,13 @@ static int smack_setprocattr(const char *name, void *value, size_t size) struct smack_known_list_elem *sklep; int rc; + /* + * Allow the /proc/.../attr/current and SO_PEERSEC "interface_lsm" + * to be reset at will. + */ + if (strcmp(name, "interface_lsm") == 0) + return 0; + if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel)) return -EPERM;