tools/nolibc: s390: disable stackprotector in _start

Message ID 20230524-nolibc-stackprotector-s390-v1-1-5044d42230cc@weissschuh.net
State New
Headers
Series tools/nolibc: s390: disable stackprotector in _start |

Commit Message

Thomas Weißschuh May 24, 2023, 4:27 p.m. UTC
  s390 does not support the "global" stack protector mode that is
implemented in nolibc.

Now that nolibc detects if stack protectors are enabled at runtime it
could happen that a future compiler does indeed use global mode on
and nolibc would compile but segfault at runtime.

To avoid this hypothetic case and to align s390 with the other
architectures disable stack protectors when compiling _start().

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-s390.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)


---
base-commit: d5d0994c2f3cae2d2bdc04b98c6212e72efe0509
change-id: 20230524-nolibc-stackprotector-s390-0bc5c197ff6f

Best regards,
  

Comments

Willy Tarreau May 24, 2023, 4:30 p.m. UTC | #1
On Wed, May 24, 2023 at 06:27:06PM +0200, Thomas Weißschuh wrote:
> s390 does not support the "global" stack protector mode that is
> implemented in nolibc.
> 
> Now that nolibc detects if stack protectors are enabled at runtime it
> could happen that a future compiler does indeed use global mode on
> and nolibc would compile but segfault at runtime.
> 
> To avoid this hypothetic case and to align s390 with the other
> architectures disable stack protectors when compiling _start().
(...)

Queued, same branch. Thanks Thomas!
Willy
  

Patch

diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index a738e7f3f8e8..516dff5bff8b 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -8,6 +8,8 @@ 
 #include <asm/signal.h>
 #include <asm/unistd.h>
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall, equivalent to stat64(). The
  * syscall returns 116 bytes and stops in the middle of __unused.
  */
@@ -164,7 +166,7 @@  char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"lg	%r2,0(%r15)\n"		/* argument count */