From 9b86d3e5de1997ed8d3153d4530bcb981e6602b9 Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Sun, 3 Oct 2021 05:03:59 +0300 Subject: [PATCH] When queuing ignored signal, only abort target thread' sleep if it is inside sigwait() Reported and tested by: trasz Reviewed by: markj Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D32252 --- sys/kern/kern_sig.c | 16 ++++++++++++++-- sys/kern/subr_sleepqueue.c | 3 ++- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c index 59e16ca8e6c..b88556f2954 100644 --- a/sys/kern/kern_sig.c +++ b/sys/kern/kern_sig.c @@ -2156,6 +2156,18 @@ tdksignal(struct thread *td, int sig, ksiginfo_t *ksi) (void) tdsendsignal(td->td_proc, td, sig, ksi); } +static int +sig_sleepq_abort(struct thread *td, int intrval) +{ + THREAD_LOCK_ASSERT(td, MA_OWNED); + + if (intrval == 0 && (td->td_flags & TDF_SIGWAIT) == 0) { + thread_unlock(td); + return (0); + } + return (sleepq_abort(td, intrval)); +} + int tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi) { @@ -2374,7 +2386,7 @@ tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi) PROC_SLOCK(p); thread_lock(td); if (TD_CAN_ABORT(td)) - wakeup_swapper = sleepq_abort(td, intrval); + wakeup_swapper = sig_sleepq_abort(td, intrval); else thread_unlock(td); PROC_SUNLOCK(p); @@ -2505,7 +2517,7 @@ tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval) if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td)) sched_prio(td, PUSER); - wakeup_swapper = sleepq_abort(td, intrval); + wakeup_swapper = sig_sleepq_abort(td, intrval); PROC_SUNLOCK(p); if (wakeup_swapper) kick_proc0(); diff --git a/sys/kern/subr_sleepqueue.c b/sys/kern/subr_sleepqueue.c index 8d61383f973..36832ef96ba 100644 --- a/sys/kern/subr_sleepqueue.c +++ b/sys/kern/subr_sleepqueue.c @@ -1126,7 +1126,8 @@ sleepq_abort(struct thread *td, int intrval) THREAD_LOCK_ASSERT(td, MA_OWNED); MPASS(TD_ON_SLEEPQ(td)); MPASS(td->td_flags & TDF_SINTR); - MPASS(intrval == 0 || intrval == EINTR || intrval == ERESTART); + MPASS((intrval == 0 && (td->td_flags & TDF_SIGWAIT) != 0) || + intrval == EINTR || intrval == ERESTART); /* * If the TDF_TIMEOUT flag is set, just leave. A -- 2.45.0