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 <[email protected]> --- fs/proc/base.c | 6 ++-- include/linux/audit.h | 42 +++++++++++++------------ include/linux/sched.h | 2 +- init/init_task.c | 2 +- kernel/audit.c | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++ kernel/auditsc.c | 84 -------------------------------------------------- 6 files changed, 113 insertions(+), 108 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 633a63462573..a23651ce6960 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1210,7 +1210,7 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, .llseek = default_llseek, }; -#ifdef CONFIG_AUDITSYSCALL +#ifdef CONFIG_AUDIT #define TMPBUFLEN 11 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, size_t count, loff_t *ppos) @@ -3002,7 +3002,7 @@ static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns, ONE("oom_score", S_IRUGO, proc_oom_score), REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), -#ifdef CONFIG_AUDITSYSCALL +#ifdef CONFIG_AUDIT REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), #endif @@ -3390,7 +3390,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask) ONE("oom_score", S_IRUGO, proc_oom_score), REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), -#ifdef CONFIG_AUDITSYSCALL +#ifdef CONFIG_AUDIT REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), #endif diff --git a/include/linux/audit.h b/include/linux/audit.h index a625c29a2ea2..ecb5d317d6a2 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -159,6 +159,18 @@ extern void audit_log_key(struct audit_buffer *ab, extern int audit_rule_change(int type, int seq, void *data, size_t datasz); extern int audit_list_rules_send(struct sk_buff *request_skb, int seq); +extern int audit_set_loginuid(kuid_t loginuid); + +static inline kuid_t audit_get_loginuid(struct task_struct *tsk) +{ + return tsk->loginuid; +} + +static inline unsigned int audit_get_sessionid(struct task_struct *tsk) +{ + return tsk->sessionid; +} + extern u32 audit_enabled; #else /* CONFIG_AUDIT */ static inline __printf(4, 5) @@ -201,6 +213,17 @@ static inline int audit_log_task_context(struct audit_buffer *ab) } static inline void audit_log_task_info(struct audit_buffer *ab) { } + +static inline kuid_t audit_get_loginuid(struct task_struct *tsk) +{ + return INVALID_UID; +} + +static inline unsigned int audit_get_sessionid(struct task_struct *tsk) +{ + return AUDIT_SID_UNSET; +} + #define audit_enabled AUDIT_OFF #endif /* CONFIG_AUDIT */ @@ -323,17 +346,6 @@ static inline void audit_ptrace(struct task_struct *t) extern unsigned int audit_serial(void); extern int auditsc_get_stamp(struct audit_context *ctx, struct timespec64 *t, unsigned int *serial); -extern int audit_set_loginuid(kuid_t loginuid); - -static inline kuid_t audit_get_loginuid(struct task_struct *tsk) -{ - return tsk->loginuid; -} - -static inline unsigned int audit_get_sessionid(struct task_struct *tsk) -{ - return tsk->sessionid; -} extern void __audit_ipc_obj(struct kern_ipc_perm *ipcp); extern void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode); @@ -519,14 +531,6 @@ static inline int auditsc_get_stamp(struct audit_context *ctx, { return 0; } -static inline kuid_t audit_get_loginuid(struct task_struct *tsk) -{ - return INVALID_UID; -} -static inline unsigned int audit_get_sessionid(struct task_struct *tsk) -{ - return AUDIT_SID_UNSET; -} static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp) { } static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t uid, diff --git a/include/linux/sched.h b/include/linux/sched.h index 89541d248893..f9788bb122c5 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -886,7 +886,7 @@ struct task_struct { struct callback_head *task_works; struct audit_context *audit_context; -#ifdef CONFIG_AUDITSYSCALL +#ifdef CONFIG_AUDIT kuid_t loginuid; unsigned int sessionid; #endif diff --git a/init/init_task.c b/init/init_task.c index 5aebe3be4d7c..39c3109acc1a 100644 --- a/init/init_task.c +++ b/init/init_task.c @@ -121,7 +121,7 @@ struct task_struct init_task .thread_pid = &init_struct_pid, .thread_group = LIST_HEAD_INIT(init_task.thread_group), .thread_node = LIST_HEAD_INIT(init_signals.thread_head), -#ifdef CONFIG_AUDITSYSCALL +#ifdef CONFIG_AUDIT .loginuid = INVALID_UID, .sessionid = AUDIT_SID_UNSET, #endif diff --git a/kernel/audit.c b/kernel/audit.c index ca55ccb46b76..dc375857c59b 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2334,6 +2334,91 @@ 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 diff --git a/kernel/auditsc.c b/kernel/auditsc.c index b585ceb2f7a2..572d247957fb 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1983,90 +1983,6 @@ int auditsc_get_stamp(struct audit_context *ctx, return 1; } -/* 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 audit_context 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_mq_open - record audit data for a POSIX MQ open * @oflag: open flag -- 1.8.3.1
