From patchwork Mon Dec 16 22:24:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 11295481 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 B24A71593 for ; Mon, 16 Dec 2019 22:24:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8672921D7D for ; Mon, 16 Dec 2019 22:24:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=yahoo.com header.i=@yahoo.com header.b="laBBXD1B" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726141AbfLPWYp (ORCPT ); Mon, 16 Dec 2019 17:24:45 -0500 Received: from sonic311-30.consmr.mail.ne1.yahoo.com ([66.163.188.211]:45106 "EHLO sonic311-30.consmr.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726664AbfLPWYo (ORCPT ); Mon, 16 Dec 2019 17:24:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1576535081; bh=xz5saF6+S5lESAas0+OpfRtJjtkIV8YymEVMS9BeV7w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=laBBXD1BYYaX6o1vvzXxVQpXC/cjrNv41WuH3c9Jhm9G/4HWaihbBNU7Vcimi13q8yB2YCT2cfYnzKEGdN5wh/MrqMBl9gdsnlqeN7IIpD3sGVsLM8LD4XL8/35IEZnQUk3X8h5JrX43zlmiV3+7ksp4qDBJwIe0Z/E2pkMGezQB35FJJ2DxqLCgfxcGDCrS6legmfeHFleolHRWoyJnTzVFnGA6csA4JxHz0hZq7stPLOKOi+gMywquUQUYtmK350rG4+01CdlPz8DI2+1iMcRMC90y9+BcEclgUHv2J8ThgR3r+8d+/pCBSY/MF5xd98kwt7omDv/BhpXyc78uLw== X-YMail-OSG: 1wkMwyIVM1nLWqaEyvU39ZavF2RJfyziKOcDYFpdaF.hRh3Bugnmb.Vo6XnNQ8o H.HuK7uSpjDa20gCw7oKhMe6ojZVymGTcT6yZ9_eC4ESgALIZ883xAGqeKOUQg0HOuL.qQQ0bipZ RZIsCRrH2pw5JrjWlJxKL3s7.nS_W.TFRMWdd8njNkGh.ItXR4Fnmab8_U26ufDir7czCVraHU1B H07zvrYU2wWDl4Pv6eQfEtreGhU0Lp9IJApPkU_dWTdk74jeDhbLLHoKMzq7OCFfsRiTZ22KVpSn TXKEXCIhohtDzKG0Eyt2OHkAc5NTUN8sTsR47TIKbl1IgrOr2NDXHXCyGNR3STouNQe1yQoHGYkx e7sqXieUfnakjL8yuI_EHlTwj1cpzb.jHPIf1dzBz.ZzuFu4_O_MaINCbyVJ2cL_l_.d_AV9ZjVq 8uE8PU92G1MZkTTPwf8a_iN21wV3TLimzvV37wuh_yhZGe.E5m0hADcrOPLGHLqP7IyMdVBVP6cQ 5Exc2cP1ObdWcJELDGDP5a80bXdNUOGfFEWh013j4Te96wBuARm60VTEa.E_wBYmkLjkQLUeNx51 ee1TGhchFiLL__VqPnlZiEBiA636wCU7eubdxeC3FlcAbCp5s6QenE00LtxZTyLA32xQbWju6Tdn DbnOyAbLYmiQo_M8GixIWofzwTuLpnew0IVt_heUnNff4jUJZ0iuiGyJCpqGz0p3mLyxwHrozRGA zc0YNRVlvdElYJmbtiyu_b8.ukIDL06h64m2hP2XtZaZS.pLrtaW.MMaik3al_kWewpnu6fiwQgJ VlHPwJRM74X3QSeUAPeS4j0XoQMqtBJh2S3i8mn5hwPBQjcl16qVkqwqV7iclW26.nlGlVhp8ngX 7ugSJefyXjHoKrAJSVPap1XLGrujDGxutWhGIgWU6RUNDiX6IhGjNXm8VExt2Zv_1kBrlXXX5Fbt WfUf.JypAZFIj4AiTVsv6gvT7WuPOQsA7vrQhvuIkSWwIRHFL5nt5B92os4Px3exCCLwbnxmHbjD fTkbH2YjhxF2cHvGJl5CwRFSPSRwCVGksGFhr4pBws4.8ymoR.0n2OwyrI2wI69Wh6oUQRc98cgy 3rjUlWBRYma7Dl_6aVTleC139WGowQZit5tsAxpuZtC70lGqqIwlARgF2_BW3vYFhM19bgZq_sdj O_GttG1aULgDOUejoePNAyM9IIXUTuvbGlDdePhy4R3_TgHTFGGRvdjvELW3b6.jw1VUHLMUaL7k Omz.65M6jsWdnW1eWCA_sK.5_BL91sD5oEbrYvOvqcOGAm4Yx3_F0NuNB83_U85PMoLxI9ZEbc6M Wzh8seUnzHtQsJ58UM6FxvPRq2j3qgugZ7G1nSd_PqhRqcieFT6N9XZFs79tLWe.LGKpDfj3N.G8 vySXS6F8rEOttvcNTgs1B8yfZQo40zhlA_.Zo8kwTX1hyRqiKviDRngcNZDRT86GBPyQN Received: from sonic.gate.mail.ne1.yahoo.com by sonic311.consmr.mail.ne1.yahoo.com with HTTP; Mon, 16 Dec 2019 22:24:41 +0000 Received: by smtp426.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID e7b8acfb3713ab7004f68eee190caaf8; Mon, 16 Dec 2019 22:24:38 +0000 (UTC) From: Casey Schaufler To: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Cc: keescook@chromium.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, sds@tycho.nsa.gov Subject: [PATCH v12 02/25] LSM: Create and manage the lsmblob data structure. Date: Mon, 16 Dec 2019 14:24:08 -0800 Message-Id: <20191216222431.4956-3-casey@schaufler-ca.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191216222431.4956-1-casey@schaufler-ca.com> References: <20191216222431.4956-1-casey@schaufler-ca.com> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: When more than one security module is exporting data to audit and networking sub-systems a single 32 bit integer is no longer sufficient to represent the data. Add a structure to be used instead. The lsmblob structure is currently an array of u32 "secids". There is an entry for each of the security modules built into the system that would use secids if active. The system assigns the module a "slot" when it registers hooks. If modules are compiled in but not registered there will be unused slots. A new lsm_id structure, which contains the name of the LSM and its slot number, is created. There is an instance for each LSM, which assigns the name and passes it to the infrastructure to set the slot. Reviewed-by: John Johansen Signed-off-by: Casey Schaufler --- include/linux/lsm_hooks.h | 12 ++++++-- include/linux/security.h | 58 ++++++++++++++++++++++++++++++++++++++ security/apparmor/lsm.c | 7 ++++- security/commoncap.c | 7 ++++- security/loadpin/loadpin.c | 8 +++++- security/safesetid/lsm.c | 8 +++++- security/security.c | 28 ++++++++++++++---- security/selinux/hooks.c | 8 +++++- security/smack/smack_lsm.c | 7 ++++- security/tomoyo/tomoyo.c | 8 +++++- security/yama/yama_lsm.c | 7 ++++- 11 files changed, 142 insertions(+), 16 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index c2b1af29a8f0..7eb808cde051 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -2077,6 +2077,14 @@ struct security_hook_heads { #endif } __randomize_layout; +/* + * Information that identifies a security module. + */ +struct lsm_id { + const char *lsm; /* Name of the LSM */ + int slot; /* Slot in lsmblob if one is allocated */ +}; + /* * Security module hook list structure. * For use with generic list macros for common operations. @@ -2085,7 +2093,7 @@ struct security_hook_list { struct hlist_node list; struct hlist_head *head; union security_list_options hook; - char *lsm; + struct lsm_id *lsmid; } __randomize_layout; /* @@ -2114,7 +2122,7 @@ extern struct security_hook_heads security_hook_heads; extern char *lsm_names; extern void security_add_hooks(struct security_hook_list *hooks, int count, - char *lsm); + struct lsm_id *lsmid); #define LSM_FLAG_LEGACY_MAJOR BIT(0) #define LSM_FLAG_EXCLUSIVE BIT(1) diff --git a/include/linux/security.h b/include/linux/security.h index 3e8d4bacd59d..b74dc70088ca 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -128,6 +128,64 @@ enum lockdown_reason { LOCKDOWN_CONFIDENTIALITY_MAX, }; +/* + * Data exported by the security modules + * + * Any LSM that provides secid or secctx based hooks must be included. + */ +#define LSMBLOB_ENTRIES ( \ + (IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \ + (IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \ + (IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0)) + +struct lsmblob { + u32 secid[LSMBLOB_ENTRIES]; +}; + +#define LSMBLOB_INVALID -1 /* Not a valid LSM slot number */ +#define LSMBLOB_NEEDED -2 /* Slot requested on initialization */ +#define LSMBLOB_NOT_NEEDED -3 /* Slot not requested */ + +/** + * lsmblob_init - initialize an lsmblob structure. + * @blob: Pointer to the data to initialize + * @secid: The initial secid value + * + * Set all secid for all modules to the specified value. + */ +static inline void lsmblob_init(struct lsmblob *blob, u32 secid) +{ + int i; + + for (i = 0; i < LSMBLOB_ENTRIES; i++) + blob->secid[i] = secid; +} + +/** + * lsmblob_is_set - report if there is an value in the lsmblob + * @blob: Pointer to the exported LSM data + * + * Returns true if there is a secid set, false otherwise + */ +static inline bool lsmblob_is_set(struct lsmblob *blob) +{ + struct lsmblob empty = {}; + + return !!memcmp(blob, &empty, sizeof(*blob)); +} + +/** + * lsmblob_equal - report if the two lsmblob's are equal + * @bloba: Pointer to one LSM data + * @blobb: Pointer to the other LSM data + * + * Returns true if all entries in the two are equal, false otherwise + */ +static inline bool lsmblob_equal(struct lsmblob *bloba, struct lsmblob *blobb) +{ + return !memcmp(bloba, blobb, sizeof(*bloba)); +} + /* 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/lsm.c b/security/apparmor/lsm.c index 61b24f4eb355..146d75e5e021 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -1147,6 +1147,11 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = { .lbs_sock = sizeof(struct aa_sk_ctx), }; +static struct lsm_id apparmor_lsmid __lsm_ro_after_init = { + .lsm = "apparmor", + .slot = LSMBLOB_NEEDED +}; + static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme), @@ -1847,7 +1852,7 @@ static int __init apparmor_init(void) goto buffers_out; } security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks), - "apparmor"); + &apparmor_lsmid); /* Report that AppArmor successfully initialized */ apparmor_initialized = 1; diff --git a/security/commoncap.c b/security/commoncap.c index f4ee0ae106b2..9dcfd2a0e891 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -1339,6 +1339,11 @@ int cap_mmap_file(struct file *file, unsigned long reqprot, #ifdef CONFIG_SECURITY +static struct lsm_id capability_lsmid __lsm_ro_after_init = { + .lsm = "capability", + .slot = LSMBLOB_NOT_NEEDED +}; + static struct security_hook_list capability_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(capable, cap_capable), LSM_HOOK_INIT(settime, cap_settime), @@ -1363,7 +1368,7 @@ static struct security_hook_list capability_hooks[] __lsm_ro_after_init = { static int __init capability_init(void) { security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks), - "capability"); + &capability_lsmid); return 0; } diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index ee5cb944f4ad..86317e78899f 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -180,6 +180,11 @@ static int loadpin_load_data(enum kernel_load_data_id id) return loadpin_read_file(NULL, (enum kernel_read_file_id) id); } +static struct lsm_id loadpin_lsmid __lsm_ro_after_init = { + .lsm = "loadpin", + .slot = LSMBLOB_NOT_NEEDED +}; + static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security), LSM_HOOK_INIT(kernel_read_file, loadpin_read_file), @@ -227,7 +232,8 @@ static int __init loadpin_init(void) pr_info("ready to pin (currently %senforcing)\n", enforce ? "" : "not "); parse_exclude(); - security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin"); + security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), + &loadpin_lsmid); return 0; } diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c index 7760019ad35d..950dfb7f931e 100644 --- a/security/safesetid/lsm.c +++ b/security/safesetid/lsm.c @@ -149,6 +149,11 @@ static int safesetid_task_fix_setuid(struct cred *new, return -EACCES; } +static struct lsm_id safesetid_lsmid __lsm_ro_after_init = { + .lsm = "safesetid", + .slot = LSMBLOB_NOT_NEEDED +}; + static struct security_hook_list safesetid_security_hooks[] = { LSM_HOOK_INIT(task_fix_setuid, safesetid_task_fix_setuid), LSM_HOOK_INIT(capable, safesetid_security_capable) @@ -157,7 +162,8 @@ static struct security_hook_list safesetid_security_hooks[] = { static int __init safesetid_security_init(void) { security_add_hooks(safesetid_security_hooks, - ARRAY_SIZE(safesetid_security_hooks), "safesetid"); + ARRAY_SIZE(safesetid_security_hooks), + &safesetid_lsmid); /* Report that SafeSetID successfully initialized */ safesetid_initialized = 1; diff --git a/security/security.c b/security/security.c index 7fb6e5bcf6ec..a89634af639a 100644 --- a/security/security.c +++ b/security/security.c @@ -308,6 +308,7 @@ static void __init ordered_lsm_init(void) init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); init_debug("task blob size = %d\n", blob_sizes.lbs_task); + init_debug("lsmblob size = %lu\n", sizeof(struct lsmblob)); /* * Create any kmem_caches needed for blobs @@ -435,21 +436,36 @@ static int lsm_append(const char *new, char **result) return 0; } +/* + * Current index to use while initializing the lsmblob secid list. + */ +static int lsm_slot __initdata; + /** * security_add_hooks - Add a modules hooks to the hook lists. * @hooks: the hooks to add * @count: the number of hooks to add - * @lsm: the name of the security module + * @lsmid: the the identification information for the security module * * Each LSM has to register its hooks with the infrastructure. + * If the LSM is using hooks that export secids allocate a slot + * for it in the lsmblob. */ void __init security_add_hooks(struct security_hook_list *hooks, int count, - char *lsm) + struct lsm_id *lsmid) { int i; + if (lsmid->slot == LSMBLOB_NEEDED) { + if (lsm_slot >= LSMBLOB_ENTRIES) + panic("%s Too many LSMs registered.\n", __func__); + lsmid->slot = lsm_slot++; + init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm, + lsmid->slot); + } + for (i = 0; i < count; i++) { - hooks[i].lsm = lsm; + hooks[i].lsmid = lsmid; hlist_add_tail_rcu(&hooks[i].list, hooks[i].head); } @@ -458,7 +474,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count, * and fix this up afterwards. */ if (slab_is_available()) { - if (lsm_append(lsm, &lsm_names) < 0) + if (lsm_append(lsmid->lsm, &lsm_names) < 0) panic("%s - Cannot get early memory.\n", __func__); } } @@ -1906,7 +1922,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name, struct security_hook_list *hp; hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsm)) + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) continue; return hp->hook.getprocattr(p, name, value); } @@ -1919,7 +1935,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value, struct security_hook_list *hp; hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsm)) + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) continue; return hp->hook.setprocattr(name, value, size); } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 0839b2fbbf9b..97f2ee6e4080 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6860,6 +6860,11 @@ static int selinux_perf_event_write(struct perf_event *event) } #endif +static struct lsm_id selinux_lsmid __lsm_ro_after_init = { + .lsm = "selinux", + .slot = LSMBLOB_NEEDED +}; + static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), @@ -7128,7 +7133,8 @@ static __init int selinux_init(void) hashtab_cache_init(); - security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); + security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), + &selinux_lsmid); if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) panic("SELinux: Unable to register AVC netcache callback\n"); diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 4cecdfdcd913..82cbb3eeec76 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -4585,6 +4585,11 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = { .lbs_sock = sizeof(struct socket_smack), }; +static struct lsm_id smack_lsmid __lsm_ro_after_init = { + .lsm = "smack", + .slot = LSMBLOB_NEEDED +}; + static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme), @@ -4783,7 +4788,7 @@ static __init int smack_init(void) /* * Register with LSM */ - security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack"); + security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid); smack_enabled = 1; pr_info("Smack: Initializing.\n"); diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c index 716c92ec941a..f1968e80f06d 100644 --- a/security/tomoyo/tomoyo.c +++ b/security/tomoyo/tomoyo.c @@ -529,6 +529,11 @@ static void tomoyo_task_free(struct task_struct *task) } } +static struct lsm_id tomoyo_lsmid __lsm_ro_after_init = { + .lsm = "tomoyo", + .slot = LSMBLOB_NOT_NEEDED +}; + /* * tomoyo_security_ops is a "struct security_operations" which is used for * registering TOMOYO. @@ -581,7 +586,8 @@ static int __init tomoyo_init(void) struct tomoyo_task *s = tomoyo_task(current); /* register ourselves with the security framework */ - security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo"); + security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), + &tomoyo_lsmid); pr_info("TOMOYO Linux initialized\n"); s->domain_info = &tomoyo_kernel_domain; atomic_inc(&tomoyo_kernel_domain.users); diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c index 94dc346370b1..0f0cf7136929 100644 --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -421,6 +421,11 @@ static int yama_ptrace_traceme(struct task_struct *parent) return rc; } +static struct lsm_id yama_lsmid __lsm_ro_after_init = { + .lsm = "yama", + .slot = LSMBLOB_NOT_NEEDED +}; + static struct security_hook_list yama_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme), @@ -477,7 +482,7 @@ static inline void yama_init_sysctl(void) { } static int __init yama_init(void) { pr_info("Yama: becoming mindful.\n"); - security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), "yama"); + security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), &yama_lsmid); yama_init_sysctl(); return 0; }