[PATCH] s390: fix stack frame handling in _dl_runtime_profile.

[PATCH] s390: fix stack frame handling in _dl_runtime_profile.

[Martin Schwidefsky]

Greetings,
a code inspection done by Curtis Taylor found a problem with the stack
pointer handling in _dl_runtime_profile. The stack frame is created with
a "aghi %r15,-160" which is fine but it is removed by a "lr %r15,%r12".
If the stack pointer in %r15 crossed a 4GB boundary with the aghi then
the stack will be off by 4GB after the lr. Not likely to happen but fatal
for the application if it does.

-- 
blue skies,
  Martin.

"Reality continues to ruin my life." - Calvin.
--

2008-11-03  Martin Schwidefsky  <schwidefsky@de.ibm.com>

	* sysdeps/s390/s390-64/dl-trampoline.S: use the correct instruction
	to remove the stack frame in _dl_runtime_profile.

diff -urpN libc/sysdeps/s390/s390-64/dl-trampoline.S libc-s390/sysdeps/s390/s390-64/dl-trampoline.S
--- libc/sysdeps/s390/s390-64/dl-trampoline.S	2005-07-11 10:54:40.000000000 +0200
+++ libc-s390/sysdeps/s390/s390-64/dl-trampoline.S	2008-11-03 13:24:03.000000000 +0100
@@ -91,7 +91,7 @@ _dl_runtime_profile:
 	ld     %f4,120(%r12)
 	ld     %f6,128(%r12)
 	basr   %r14,%r1			# call resolved function
-0:	lr     %r15,%r12		# remove stack frame
+0:	lgr    %r15,%r12		# remove stack frame
 	cfi_def_cfa_register (15)
 	lg     %r14,32(%r15)		# restore registers
 	lg     %r12,24(%r15)

Re: [PATCH] s390: fix stack frame handling in _dl_runtime_profile.

[Jakub Jelinek]

On Mon, Nov 03, 2008 at 01:35:59PM +0100, Martin Schwidefsky wrote:
> 2008-11-03  Martin Schwidefsky  <schwidefsky@de.ibm.com>
> 
> 	* sysdeps/s390/s390-64/dl-trampoline.S: use the correct instruction
> 	to remove the stack frame in _dl_runtime_profile.

Committed after fixing up ChangeLog entry.  Thanks.

	Jakub