diff options
Diffstat (limited to 'kernel/signal.c')
| -rw-r--r-- | kernel/signal.c | 62 |
1 files changed, 58 insertions, 4 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index ef8f2a28d37c..c37170655171 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -984,7 +984,7 @@ static inline bool wants_signal(int sig, struct task_struct *p) if (task_is_stopped_or_traced(p)) return false; - return task_curr(p) || !signal_pending(p); + return task_curr(p) || !task_sigpending(p); } static void complete_signal(int sig, struct task_struct *p, enum pid_type type) @@ -2524,12 +2524,46 @@ static int ptrace_signal(int signr, kernel_siginfo_t *info) return signr; } +static void hide_si_addr_tag_bits(struct ksignal *ksig) +{ + switch (siginfo_layout(ksig->sig, ksig->info.si_code)) { + case SIL_FAULT: + case SIL_FAULT_MCEERR: + case SIL_FAULT_BNDERR: + case SIL_FAULT_PKUERR: + ksig->info.si_addr = arch_untagged_si_addr( + ksig->info.si_addr, ksig->sig, ksig->info.si_code); + break; + case SIL_KILL: + case SIL_TIMER: + case SIL_POLL: + case SIL_CHLD: + case SIL_RT: + case SIL_SYS: + break; + } +} + bool get_signal(struct ksignal *ksig) { struct sighand_struct *sighand = current->sighand; struct signal_struct *signal = current->signal; int signr; + /* + * For non-generic architectures, check for TIF_NOTIFY_SIGNAL so + * that the arch handlers don't all have to do it. If we get here + * without TIF_SIGPENDING, just exit after running signal work. + */ +#ifdef TIF_NOTIFY_SIGNAL + if (!IS_ENABLED(CONFIG_GENERIC_ENTRY)) { + if (test_thread_flag(TIF_NOTIFY_SIGNAL)) + tracehook_notify_signal(); + if (!task_sigpending(current)) + return false; + } +#endif + if (unlikely(uprobe_deny_signal())) return false; @@ -2761,6 +2795,10 @@ relock: spin_unlock_irq(&sighand->siglock); ksig->sig = signr; + + if (!(ksig->ka.sa.sa_flags & SA_EXPOSE_TAGBITS)) + hide_si_addr_tag_bits(ksig); + return ksig->sig > 0; } @@ -2823,7 +2861,7 @@ static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) /* Remove the signals this thread can handle. */ sigandsets(&retarget, &retarget, &t->blocked); - if (!signal_pending(t)) + if (!task_sigpending(t)) signal_wake_up(t, 0); if (sigisemptyset(&retarget)) @@ -2857,7 +2895,7 @@ void exit_signals(struct task_struct *tsk) cgroup_threadgroup_change_end(tsk); - if (!signal_pending(tsk)) + if (!task_sigpending(tsk)) goto out; unblocked = tsk->blocked; @@ -2901,7 +2939,7 @@ long do_no_restart_syscall(struct restart_block *param) static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset) { - if (signal_pending(tsk) && !thread_group_empty(tsk)) { + if (task_sigpending(tsk) && !thread_group_empty(tsk)) { sigset_t newblocked; /* A set of now blocked but previously unblocked signals. */ sigandnsets(&newblocked, newset, ¤t->blocked); @@ -3985,6 +4023,22 @@ int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) if (oact) *oact = *k; + /* + * Make sure that we never accidentally claim to support SA_UNSUPPORTED, + * e.g. by having an architecture use the bit in their uapi. + */ + BUILD_BUG_ON(UAPI_SA_FLAGS & SA_UNSUPPORTED); + + /* + * Clear unknown flag bits in order to allow userspace to detect missing + * support for flag bits and to allow the kernel to use non-uapi bits + * internally. + */ + if (act) + act->sa.sa_flags &= UAPI_SA_FLAGS; + if (oact) + oact->sa.sa_flags &= UAPI_SA_FLAGS; + sigaction_compat_abi(act, oact); if (act) { |