From 53fc7a01df51f58b317ea5ab1607a1af65d6d4cf Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Mon, 10 Dec 2018 17:17:48 -0500 Subject: audit: give a clue what CONFIG_CHANGE op was involved The failure to add an audit rule due to audit locked gives no clue what CONFIG_CHANGE operation failed. Similarly the set operation is the only other operation that doesn't give the "op=" field to indicate the action. All other CONFIG_CHANGE records include an op= field to give a clue as to what sort of configuration change is being executed. Since these are the only CONFIG_CHANGE records that that do not have an op= field, add them to bring them in line with the rest. Old records: type=CONFIG_CHANGE msg=audit(1519812997.781:374): pid=610 uid=0 auid=0 ses=1 subj=... audit_enabled=2 res=0 type=CONFIG_CHANGE msg=audit(2018-06-14 14:55:04.507:47) : audit_enabled=1 old=1 auid=unset ses=unset subj=... res=yes New records: type=CONFIG_CHANGE msg=audit(1520958477.855:100): pid=610 uid=0 auid=0 ses=1 subj=... op=add_rule audit_enabled=2 res=0 type=CONFIG_CHANGE msg=audit(2018-06-14 14:55:04.507:47) : op=set audit_enabled=1 old=1 auid=unset ses=unset subj=... res=yes See: https://github.com/linux-audit/audit-kernel/issues/59 Signed-off-by: Richard Guy Briggs [PM: fixed checkpatch.pl line length problems] Signed-off-by: Paul Moore --- kernel/audit.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index 632d36059556..d412fb4ae6d5 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -399,7 +399,7 @@ static int audit_log_config_change(char *function_name, u32 new, u32 old, ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (unlikely(!ab)) return rc; - audit_log_format(ab, "%s=%u old=%u ", function_name, new, old); + audit_log_format(ab, "op=set %s=%u old=%u ", function_name, new, old); audit_log_session_info(ab); rc = audit_log_task_context(ab); if (rc) @@ -1362,7 +1362,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return -EINVAL; if (audit_enabled == AUDIT_LOCKED) { audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); - audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled); + audit_log_format(ab, " op=%s audit_enabled=%d res=0", + msg_type == AUDIT_ADD_RULE ? + "add_rule" : "remove_rule", + audit_enabled); audit_log_end(ab); return -EPERM; } -- cgit v1.2.3 From 626abcd13d4ea2b67be3249a250046cf713f532a Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Fri, 18 Jan 2019 17:42:48 -0500 Subject: audit: add syscall information to CONFIG_CHANGE records Tie syscall information to all CONFIG_CHANGE calls since they are all a result of user actions. Exclude user records from syscall context: Since the function audit_log_common_recv_msg() is shared by a number of AUDIT_CONFIG_CHANGE and the entire range of AUDIT_USER_* record types, and since the AUDIT_CONFIG_CHANGE message type has been converted to a syscall accompanied record type, special-case the AUDIT_USER_* range of messages so they remain standalone records. See: https://github.com/linux-audit/audit-kernel/issues/59 See: https://github.com/linux-audit/audit-kernel/issues/50 Signed-off-by: Richard Guy Briggs [PM: fix line lengths in kernel/audit.c] Signed-off-by: Paul Moore --- kernel/audit.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index d412fb4ae6d5..c2a7662cc254 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -396,7 +396,7 @@ static int audit_log_config_change(char *function_name, u32 new, u32 old, struct audit_buffer *ab; int rc = 0; - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); + ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (unlikely(!ab)) return rc; audit_log_format(ab, "op=set %s=%u old=%u ", function_name, new, old); @@ -1053,7 +1053,8 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) return err; } -static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) +static void audit_log_common_recv_msg(struct audit_context *context, + struct audit_buffer **ab, u16 msg_type) { uid_t uid = from_kuid(&init_user_ns, current_uid()); pid_t pid = task_tgid_nr(current); @@ -1063,7 +1064,7 @@ static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) return; } - *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); + *ab = audit_log_start(context, GFP_KERNEL, msg_type); if (unlikely(!*ab)) return; audit_log_format(*ab, "pid=%d uid=%u ", pid, uid); @@ -1071,6 +1072,12 @@ static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) audit_log_task_context(*ab); } +static inline void audit_log_user_recv_msg(struct audit_buffer **ab, + u16 msg_type) +{ + audit_log_common_recv_msg(NULL, ab, msg_type); +} + int is_audit_feature_set(int i) { return af.features & AUDIT_FEATURE_TO_MASK(i); @@ -1338,7 +1345,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (err) break; } - audit_log_common_recv_msg(&ab, msg_type); + audit_log_user_recv_msg(&ab, msg_type); if (msg_type != AUDIT_USER_TTY) audit_log_format(ab, " msg='%.*s'", AUDIT_MESSAGE_TEXT_MAX, @@ -1361,7 +1368,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (nlmsg_len(nlh) < sizeof(struct audit_rule_data)) return -EINVAL; if (audit_enabled == AUDIT_LOCKED) { - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); + audit_log_common_recv_msg(audit_context(), &ab, + AUDIT_CONFIG_CHANGE); audit_log_format(ab, " op=%s audit_enabled=%d res=0", msg_type == AUDIT_ADD_RULE ? "add_rule" : "remove_rule", @@ -1376,7 +1384,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) break; case AUDIT_TRIM: audit_trim_trees(); - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); + audit_log_common_recv_msg(audit_context(), &ab, + AUDIT_CONFIG_CHANGE); audit_log_format(ab, " op=trim res=1"); audit_log_end(ab); break; @@ -1406,8 +1415,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) /* OK, here comes... */ err = audit_tag_tree(old, new); - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); - + audit_log_common_recv_msg(audit_context(), &ab, + AUDIT_CONFIG_CHANGE); audit_log_format(ab, " op=make_equiv old="); audit_log_untrustedstring(ab, old); audit_log_format(ab, " new="); @@ -1474,7 +1483,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) old.enabled = t & AUDIT_TTY_ENABLE; old.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD); - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); + audit_log_common_recv_msg(audit_context(), &ab, + AUDIT_CONFIG_CHANGE); audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d" " old-log_passwd=%d new-log_passwd=%d res=%d", old.enabled, s.enabled, old.log_passwd, -- cgit v1.2.3 From 4b7d248b3a1de483ffe9d05c1debbf32a544164d Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Tue, 22 Jan 2019 17:06:39 -0500 Subject: audit: move loginuid and sessionid from CONFIG_AUDITSYSCALL to CONFIG_AUDIT loginuid and sessionid (and audit_log_session_info) should be part of CONFIG_AUDIT scope and not CONFIG_AUDITSYSCALL since it is used in CONFIG_CHANGE, ANOM_LINK, FEATURE_CHANGE (and INTEGRITY_RULE), none of which are otherwise dependent on AUDITSYSCALL. Please see github issue https://github.com/linux-audit/audit-kernel/issues/104 Signed-off-by: Richard Guy Briggs [PM: tweaked subject line for better grep'ing] Signed-off-by: Paul Moore --- kernel/audit.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index c2a7662cc254..2a32f304223d 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2335,6 +2335,91 @@ void audit_log_link_denied(const char *operation) audit_log_end(ab); } +/* global counter which is incremented every time something logs in */ +static atomic_t session_id = ATOMIC_INIT(0); + +static int audit_set_loginuid_perm(kuid_t loginuid) +{ + /* if we are unset, we don't need privs */ + if (!audit_loginuid_set(current)) + return 0; + /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/ + if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE)) + return -EPERM; + /* it is set, you need permission */ + if (!capable(CAP_AUDIT_CONTROL)) + return -EPERM; + /* reject if this is not an unset and we don't allow that */ + if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) + && uid_valid(loginuid)) + return -EPERM; + return 0; +} + +static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, + unsigned int oldsessionid, + unsigned int sessionid, int rc) +{ + struct audit_buffer *ab; + uid_t uid, oldloginuid, loginuid; + struct tty_struct *tty; + + if (!audit_enabled) + return; + + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); + if (!ab) + return; + + uid = from_kuid(&init_user_ns, task_uid(current)); + oldloginuid = from_kuid(&init_user_ns, koldloginuid); + loginuid = from_kuid(&init_user_ns, kloginuid), + tty = audit_get_tty(); + + audit_log_format(ab, "pid=%d uid=%u", task_tgid_nr(current), uid); + audit_log_task_context(ab); + audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d", + oldloginuid, loginuid, tty ? tty_name(tty) : "(none)", + oldsessionid, sessionid, !rc); + audit_put_tty(tty); + audit_log_end(ab); +} + +/** + * audit_set_loginuid - set current task's loginuid + * @loginuid: loginuid value + * + * Returns 0. + * + * Called (set) from fs/proc/base.c::proc_loginuid_write(). + */ +int audit_set_loginuid(kuid_t loginuid) +{ + unsigned int oldsessionid, sessionid = AUDIT_SID_UNSET; + kuid_t oldloginuid; + int rc; + + oldloginuid = audit_get_loginuid(current); + oldsessionid = audit_get_sessionid(current); + + rc = audit_set_loginuid_perm(loginuid); + if (rc) + goto out; + + /* are we setting or clearing? */ + if (uid_valid(loginuid)) { + sessionid = (unsigned int)atomic_inc_return(&session_id); + if (unlikely(sessionid == AUDIT_SID_UNSET)) + sessionid = (unsigned int)atomic_inc_return(&session_id); + } + + current->sessionid = sessionid; + current->loginuid = loginuid; +out: + audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc); + return rc; +} + /** * audit_log_end - end one audit record * @ab: the audit_buffer -- cgit v1.2.3 From 2fec30e245a3b46fef89c4cb1f74eefc5fbb29a6 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Wed, 23 Jan 2019 21:36:25 -0500 Subject: audit: add support for fcaps v3 V3 namespaced file capabilities were introduced in commit 8db6c34f1dbc ("Introduce v3 namespaced file capabilities") Add support for these by adding the "frootid" field to the existing fcaps fields in the NAME and BPRM_FCAPS records. Please see github issue https://github.com/linux-audit/audit-kernel/issues/103 Signed-off-by: Richard Guy Briggs Acked-by: Serge Hallyn [PM: comment tweak to fit an 80 char line width] Signed-off-by: Paul Moore --- kernel/audit.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index 2a32f304223d..3f3f1888cac7 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2084,8 +2084,9 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) { audit_log_cap(ab, "cap_fp", &name->fcap.permitted); audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); - audit_log_format(ab, " cap_fe=%d cap_fver=%x", - name->fcap.fE, name->fcap_ver); + audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", + name->fcap.fE, name->fcap_ver, + from_kuid(&init_user_ns, name->fcap.rootid)); } static inline int audit_copy_fcaps(struct audit_names *name, @@ -2104,6 +2105,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, name->fcap.permitted = caps.permitted; name->fcap.inheritable = caps.inheritable; name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); + name->fcap.rootid = caps.rootid; name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; -- cgit v1.2.3 From 57d4657716aca81ef4d7ec23e8123d26e3d28954 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Wed, 23 Jan 2019 13:35:00 -0500 Subject: audit: ignore fcaps on umount Don't fetch fcaps when umount2 is called to avoid a process hang while it waits for the missing resource to (possibly never) re-appear. Note the comment above user_path_mountpoint_at(): * A umount is a special case for path walking. We're not actually interested * in the inode in this situation, and ESTALE errors can be a problem. We * simply want track down the dentry and vfsmount attached at the mountpoint * and avoid revalidating the last component. This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. Please see the github issue tracker https://github.com/linux-audit/audit-kernel/issues/100 Signed-off-by: Richard Guy Briggs [PM: merge fuzz in audit_log_fcaps()] Signed-off-by: Paul Moore --- kernel/audit.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index 3f3f1888cac7..b7177a8def2e 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2082,6 +2082,10 @@ void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) { + if (name->fcap_ver == -1) { + audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); + return; + } audit_log_cap(ab, "cap_fp", &name->fcap.permitted); audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", @@ -2114,7 +2118,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, /* Copy inode data into an audit_names. */ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode) + struct inode *inode, unsigned int flags) { name->ino = inode->i_ino; name->dev = inode->i_sb->s_dev; @@ -2123,6 +2127,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, name->gid = inode->i_gid; name->rdev = inode->i_rdev; security_inode_getsecid(inode, &name->osid); + if (flags & AUDIT_INODE_NOEVAL) { + name->fcap_ver = -1; + return; + } audit_copy_fcaps(name, dentry); } -- cgit v1.2.3 From 5f3d544f1671d214cd26e45bda326f921455256e Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Fri, 1 Feb 2019 22:45:17 -0500 Subject: audit: remove audit_context when CONFIG_ AUDIT and not AUDITSYSCALL Remove audit_context from struct task_struct and struct audit_buffer when CONFIG_AUDIT is enabled but CONFIG_AUDITSYSCALL is not. Also, audit_log_name() (and supporting inode and fcaps functions) should have been put back in auditsc.c when soft and hard link logging was normalized since it is only used by syscall auditing. See github issue https://github.com/linux-audit/audit-kernel/issues/105 Signed-off-by: Richard Guy Briggs Signed-off-by: Paul Moore --- kernel/audit.c | 157 --------------------------------------------------------- 1 file changed, 157 deletions(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index b7177a8def2e..c89ea48c70a6 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2067,163 +2067,6 @@ void audit_log_key(struct audit_buffer *ab, char *key) audit_log_format(ab, "(null)"); } -void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) -{ - int i; - - if (cap_isclear(*cap)) { - audit_log_format(ab, " %s=0", prefix); - return; - } - audit_log_format(ab, " %s=", prefix); - CAP_FOR_EACH_U32(i) - audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]); -} - -static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) -{ - if (name->fcap_ver == -1) { - audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); - return; - } - audit_log_cap(ab, "cap_fp", &name->fcap.permitted); - audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); - audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", - name->fcap.fE, name->fcap_ver, - from_kuid(&init_user_ns, name->fcap.rootid)); -} - -static inline int audit_copy_fcaps(struct audit_names *name, - const struct dentry *dentry) -{ - struct cpu_vfs_cap_data caps; - int rc; - - if (!dentry) - return 0; - - rc = get_vfs_caps_from_disk(dentry, &caps); - if (rc) - return rc; - - name->fcap.permitted = caps.permitted; - name->fcap.inheritable = caps.inheritable; - name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); - name->fcap.rootid = caps.rootid; - name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> - VFS_CAP_REVISION_SHIFT; - - return 0; -} - -/* Copy inode data into an audit_names. */ -void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode, unsigned int flags) -{ - name->ino = inode->i_ino; - name->dev = inode->i_sb->s_dev; - name->mode = inode->i_mode; - name->uid = inode->i_uid; - name->gid = inode->i_gid; - name->rdev = inode->i_rdev; - security_inode_getsecid(inode, &name->osid); - if (flags & AUDIT_INODE_NOEVAL) { - name->fcap_ver = -1; - return; - } - audit_copy_fcaps(name, dentry); -} - -/** - * audit_log_name - produce AUDIT_PATH record from struct audit_names - * @context: audit_context for the task - * @n: audit_names structure with reportable details - * @path: optional path to report instead of audit_names->name - * @record_num: record number to report when handling a list of names - * @call_panic: optional pointer to int that will be updated if secid fails - */ -void audit_log_name(struct audit_context *context, struct audit_names *n, - const struct path *path, int record_num, int *call_panic) -{ - struct audit_buffer *ab; - ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); - if (!ab) - return; - - audit_log_format(ab, "item=%d", record_num); - - if (path) - audit_log_d_path(ab, " name=", path); - else if (n->name) { - switch (n->name_len) { - case AUDIT_NAME_FULL: - /* log the full path */ - audit_log_format(ab, " name="); - audit_log_untrustedstring(ab, n->name->name); - break; - case 0: - /* name was specified as a relative path and the - * directory component is the cwd */ - audit_log_d_path(ab, " name=", &context->pwd); - break; - default: - /* log the name's directory component */ - audit_log_format(ab, " name="); - audit_log_n_untrustedstring(ab, n->name->name, - n->name_len); - } - } else - audit_log_format(ab, " name=(null)"); - - if (n->ino != AUDIT_INO_UNSET) - audit_log_format(ab, " inode=%lu" - " dev=%02x:%02x mode=%#ho" - " ouid=%u ogid=%u rdev=%02x:%02x", - n->ino, - MAJOR(n->dev), - MINOR(n->dev), - n->mode, - from_kuid(&init_user_ns, n->uid), - from_kgid(&init_user_ns, n->gid), - MAJOR(n->rdev), - MINOR(n->rdev)); - if (n->osid != 0) { - char *ctx = NULL; - u32 len; - if (security_secid_to_secctx( - n->osid, &ctx, &len)) { - audit_log_format(ab, " osid=%u", n->osid); - if (call_panic) - *call_panic = 2; - } else { - audit_log_format(ab, " obj=%s", ctx); - security_release_secctx(ctx, len); - } - } - - /* log the audit_names record type */ - switch(n->type) { - case AUDIT_TYPE_NORMAL: - audit_log_format(ab, " nametype=NORMAL"); - break; - case AUDIT_TYPE_PARENT: - audit_log_format(ab, " nametype=PARENT"); - break; - case AUDIT_TYPE_CHILD_DELETE: - audit_log_format(ab, " nametype=DELETE"); - break; - case AUDIT_TYPE_CHILD_CREATE: - audit_log_format(ab, " nametype=CREATE"); - break; - default: - audit_log_format(ab, " nametype=UNKNOWN"); - break; - } - - audit_log_fcaps(ab, n); - audit_log_end(ab); -} - int audit_log_task_context(struct audit_buffer *ab) { char *ctx = NULL; -- cgit v1.2.3