diff options
| -rw-r--r-- | kernel/signal.c | 67 |
1 files changed, 40 insertions, 27 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index 18040d6bd63a..39a3eca5ce22 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1056,27 +1056,6 @@ static inline bool legacy_queue(struct sigpending *signals, int sig) return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); } -#ifdef CONFIG_USER_NS -static inline void userns_fixup_signal_uid(struct kernel_siginfo *info, struct task_struct *t) -{ - if (current_user_ns() == task_cred_xxx(t, user_ns)) - return; - - if (SI_FROMKERNEL(info)) - return; - - rcu_read_lock(); - info->si_uid = from_kuid_munged(task_cred_xxx(t, user_ns), - make_kuid(current_user_ns(), info->si_uid)); - rcu_read_unlock(); -} -#else -static inline void userns_fixup_signal_uid(struct kernel_siginfo *info, struct task_struct *t) -{ - return; -} -#endif - static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t, enum pid_type type, int from_ancestor_ns) { @@ -1134,7 +1113,11 @@ static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struc q->info.si_code = SI_USER; q->info.si_pid = task_tgid_nr_ns(current, task_active_pid_ns(t)); - q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); + rcu_read_lock(); + q->info.si_uid = + from_kuid_munged(task_cred_xxx(t, user_ns), + current_uid()); + rcu_read_unlock(); break; case (unsigned long) SEND_SIG_PRIV: clear_siginfo(&q->info); @@ -1146,13 +1129,8 @@ static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struc break; default: copy_siginfo(&q->info, info); - if (from_ancestor_ns) - q->info.si_pid = 0; break; } - - userns_fixup_signal_uid(&q->info, t); - } else if (!is_si_special(info)) { if (sig >= SIGRTMIN && info->si_code != SI_USER) { /* @@ -1196,6 +1174,28 @@ ret: return ret; } +static inline bool has_si_pid_and_uid(struct kernel_siginfo *info) +{ + bool ret = false; + switch (siginfo_layout(info->si_signo, info->si_code)) { + case SIL_KILL: + case SIL_CHLD: + case SIL_RT: + ret = true; + break; + case SIL_TIMER: + case SIL_POLL: + case SIL_FAULT: + case SIL_FAULT_MCEERR: + case SIL_FAULT_BNDERR: + case SIL_FAULT_PKUERR: + case SIL_SYS: + ret = false; + break; + } + return ret; +} + static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t, enum pid_type type) { @@ -1205,7 +1205,20 @@ static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct from_ancestor_ns = si_fromuser(info) && !task_pid_nr_ns(current, task_active_pid_ns(t)); #endif + if (!is_si_special(info) && has_si_pid_and_uid(info)) { + struct user_namespace *t_user_ns; + rcu_read_lock(); + t_user_ns = task_cred_xxx(t, user_ns); + if (current_user_ns() != t_user_ns) { + kuid_t uid = make_kuid(current_user_ns(), info->si_uid); + info->si_uid = from_kuid_munged(t_user_ns, uid); + } + rcu_read_unlock(); + + if (!task_pid_nr_ns(current, task_active_pid_ns(t))) + info->si_pid = 0; + } return __send_signal(sig, info, t, type, from_ancestor_ns); } |