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

posix_spawn: fix child spinning on write to a broken pipe

Browse source 
A child process created by posix_spawn reports errors to its parent via
a pipe, retrying infinitely on any write error to prevent falsely
reporting success. If the (original) parent dies before write is
attempted, there is nobody to report to, but the child will remain
stuck in the write loop forever if SIGPIPE is blocked or ignored.
Fix this by not retrying write if it fails with EPIPE.
This commit is contained in:
Alexey Izbyshev 2024-02-29 14:13:18 +03:00 • committed by Rich Felker
parent 80e3b09823
commit d3a61059c0
1 changed files with 6 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
src/process/posix_spawn.c
View file

@ -4,6 +4,7 @@
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/wait.h>
#include "syscall.h"
#include "lock.h"
@ -156,7 +157,11 @@ static int child(void *args_vp)
fail:
/* Since sizeof errno < PIPE_BUF, the write is atomic. */
ret = -ret;
if (ret) while (__syscall(SYS_write, p, &ret, sizeof ret) < 0);
if (ret) {
int r;
do r = __syscall(SYS_write, p, &ret, sizeof ret);
while (r<0 && r!=-EPIPE);
}
_exit(127);
}