1 files changed, 19 insertions, 0 deletions

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index e39290dd43c9..b57f6b6e5b9d 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -952,6 +952,7 @@ sigdflt(struct sigacts *ps, int sig)
 void
 execsigs(struct proc *p)
 {
+	sigset_t osigignore;
 	struct sigacts *ps;
 	int sig;
 	struct thread *td;
@@ -971,6 +972,24 @@ execsigs(struct proc *p)
 		if ((sigprop(sig) & SA_IGNORE) != 0)
 			sigqueue_delete_proc(p, sig);
 	}
+
+	/*
+	 * As CloudABI processes cannot modify signal handlers, fully
+	 * reset all signals to their default behavior. Do ignore
+	 * SIGPIPE, as it would otherwise be impossible to recover from
+	 * writes to broken pipes and sockets.
+	 */
+	if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
+		osigignore = ps->ps_sigignore;
+		while (SIGNOTEMPTY(osigignore)) {
+			sig = sig_ffs(&osigignore);
+			SIGDELSET(osigignore, sig);
+			if (sig != SIGPIPE)
+				sigdflt(ps, sig);
+		}
+		SIGADDSET(ps->ps_sigignore, SIGPIPE);
+	}
+
 	/*
 	 * Reset stack state to the user stack.
 	 * Clear set of signals caught on the signal stack.