From 271ab2406f0d082c5ca46dc6755ede9de2d0fc20 Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Fri, 16 Jan 2015 07:06:58 +0000 Subject: [PATCH] For sigaction(2), ignore possible garbage in sa_flags for sa_handler == SIG_DFL or SIG_IGN. Sloppy code does not fully initialize struct sigaction for such cases, and being too demanding in the case of default handler does not catch anything. Reported and tested by: Alex Tutubalin Sponsored by: The FreeBSD Foundation MFC after: 1 week --- sys/kern/kern_sig.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c index a4f0f889005..06d8e9924f8 100644 --- a/sys/kern/kern_sig.c +++ b/sys/kern/kern_sig.c @@ -653,9 +653,10 @@ kern_sigaction(td, sig, act, oact, flags) if (!_SIG_VALID(sig)) return (EINVAL); - if (act != NULL && (act->sa_flags & ~(SA_ONSTACK | SA_RESTART | - SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER | SA_NOCLDWAIT | - SA_SIGINFO)) != 0) + if (act != NULL && act->sa_handler != SIG_DFL && + act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK | + SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER | + SA_NOCLDWAIT | SA_SIGINFO)) != 0) return (EINVAL); PROC_LOCK(p);