system/musl: more POSIX

1 files changed, 55 insertions, 0 deletions

diff --git a/system/musl/0007-abort-raise-SIGABRT-again-if-signal-is-ignored.patch b/system/musl/0007-abort-raise-SIGABRT-again-if-signal-is-ignored.patch
new file mode 100644
index 000000000..4ab303c7d
--- /dev/null
+++ b/system/musl/0007-abort-raise-SIGABRT-again-if-signal-is-ignored.patch
@@ -0,0 +1,55 @@
+From 1316aae0c862240ff58b1cf38c92cd8cefd02a91 Mon Sep 17 00:00:00 2001
+From: "A. Wilcox" <AWilcox@Wilcox-Tech.com>
+Date: Tue, 17 Apr 2018 22:08:48 -0500
+Subject: [PATCH 7/7] abort: raise SIGABRT again if signal is ignored
+
+POSIX requires that abort() gives the SIGABRT status to waitpid(3) and
+friends.  If a signal handler is installed, and erroneously returns,
+then the status given to waitpid(3) is SIGSEGV instead of SIGABRT.
+
+This change gives another opportunity for the proper SIGABRT status to
+be given to any process monitoring this one's process, before we fall
+back to a_crash(), which should be sufficient.
+---
+ src/exit/abort.c | 18 ++++++++++++++++++
+ 1 file changed, 18 insertions(+)
+
+diff --git a/src/exit/abort.c b/src/exit/abort.c
+index ecc0f735..5e5a87c3 100644
+--- a/src/exit/abort.c
++++ b/src/exit/abort.c
+@@ -1,13 +1,31 @@
+ #include <stdlib.h>
+ #include <signal.h>
++#include <string.h>
+ #include "syscall.h"
+ #include "pthread_impl.h"
+ #include "atomic.h"
+ 
+ _Noreturn void abort(void)
+ {
++	struct sigaction abrtaction;
++	sigset_t abrtset;
++
+ 	raise(SIGABRT);
+ 	__block_all_sigs(0);
++
++	/* Unblock just SIGABRT, and set default handler */
++	sigemptyset(&abrtset);
++	sigaddset(&abrtset, SIGABRT);
++	sigprocmask(SIG_UNBLOCK, &abrtset, 0);
++
++	memset(&abrtaction, 0, sizeof(struct sigaction));
++	abrtaction.sa_handler = SIG_DFL;
++
++	sigaction(SIGABRT, &abrtaction, NULL);
++
++	raise(SIGABRT);
++
++	/* Ok, give up. */
+ 	a_crash();
+ 	raise(SIGKILL);
+ 	_Exit(127);
+-- 
+2.15.0
+