Message-ID: <545D935F.3070300@lekkertech.net>
Date: Fri, 07 Nov 2014 19:51:59 -0800
From: Willem Pinckaers <willem_qemu@lekkertech.net>
MIME-Version: 1.0
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Subject: [Qemu-devel] [PATCH] coroutine-sigaltstack: Change jmp_buf to
	sigjmp_buf
To: qemu-devel@nongnu.org
Cc: qemu-trivial@nongnu.org


This is a simple patch to change the type of old_env from jmp_buf
to sigjmp_buf.  old_env is used by sigsetjmp and as such should be
a sigjmp_buf.

This fixes a stack_chk fail in a OSX 32bit build. Since at least on
OSX sigjmp_buf is four bytes larger then a jmpbuf, resulting in an
overflow in sigsetjmp. Due to variable reordering this overwrites
the stack cookie.

Signed-off-by: Willem Pinckaers <willem_qemu@lekkertech.net>
---
 coroutine-sigaltstack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/coroutine-sigaltstack.c b/coroutine-sigaltstack.c
index 3de0bb3..63519ff 100644
--- a/coroutine-sigaltstack.c
+++ b/coroutine-sigaltstack.c
@@ -155,7 +155,7 @@ Coroutine *qemu_coroutine_new(void)
     stack_t oss;
     sigset_t sigs;
     sigset_t osigs;
-    jmp_buf old_env;
+    sigjmp_buf old_env;

     /* The way to manipulate stack is with the sigaltstack function. We
      * prepare a stack, with it delivering a signal to ourselves and then
-- 
1.9.3 (Apple Git-50)