The signal handler for SIGALRM calls longjmp, but the handler is installed before the jump target has been initialized. If another process sends SIGALRM right between handler installation and target initialization, the jump leads to undefined behavior.
This can easily be fixed by moving the signal handler installation into the "SETJMP == 0" conditional block, which means that the target has just been initialized. Signed-off-by: Tobias Stoeckmann <[email protected]> --- src/utils.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/utils.c b/src/utils.c index b07da9f..e42bb8f 100644 --- a/src/utils.c +++ b/src/utils.c @@ -2045,13 +2045,16 @@ run_with_timeout (double timeout, void (*fun) (void *), void *arg) return false; } - signal (SIGALRM, abort_run_with_timeout); if (SETJMP (run_with_timeout_env) != 0) { /* Longjumped out of FUN with a timeout. */ signal (SIGALRM, SIG_DFL); return true; } + else + { + signal (SIGALRM, abort_run_with_timeout); + } alarm_set (timeout); fun (arg); -- 2.9.2
