niansa-misc/musl
1
0
Fork 0
mirror of git://git.musl-libc.org/musl synced 2025-03-06 20:48:29 +01:00
Code Issues Projects Releases Packages Wiki Activity

SIGEV_THREAD timers: fix fatal signal if internal SIGTIMER becomes unblocked

Browse source 
commit 6ae2568bc2 introduced a fatal
signal condition if the internal timer signal used for SIGEV_THREAD
timers is unblocked. this can happen whenever the application alters
the signal mask with SIG_SETMASK, since sigset_t objects never include
the bits used for implementation-internal signals.

this patch effectively reverts the breakage by adding back a no-op
signal handler.

overruns will not be accounted if the timer signal becomes unblocked,
but POSIX does not specify them except for SIGEV_SIGNAL timers anyway.
This commit is contained in:
Rich Felker 2024-12-13 11:31:40 +00:00
parent 61399d4bd0
commit 47fa6e4fcc
1 changed files with 8 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
src/time/timer_create.c
View file

@ -22,6 +22,10 @@ static void dummy_0()
}
weak_alias(dummy_0, __pthread_tsd_run_dtors);
static void timer_handler(int sig, siginfo_t *si, void *ctx)
{
}
static void cleanup_fromsig(void *p)
{
pthread_t self = __pthread_self();
@ -98,7 +102,10 @@ int timer_create(clockid_t clk, struct sigevent *restrict evp, timer_t *restrict
break;
case SIGEV_THREAD:
if (!init) {
struct sigaction sa = { .sa_handler = SIG_DFL };
struct sigaction sa = {
.sa_sigaction = timer_handler,
.sa_flags = SA_SIGINFO | SA_RESTART
};
__libc_sigaction(SIGTIMER, &sa, 0);
a_store(&init, 1);
}