Commit-ID: f05058c4d652b619adfda6c78d8f5b341169c264 Gitweb: http://git.kernel.org/tip/f05058c4d652b619adfda6c78d8f5b341169c264 Author: Chris J Arges <[email protected]> AuthorDate: Thu, 21 Jan 2016 16:49:25 -0600 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 24 Feb 2016 08:35:43 +0100
x86/uaccess: Add stack frame output operand in get_user() inline asm Numerous 'call without frame pointer save/setup' warnings are introduced by stacktool because of functions using the get_user() macro. Bad stack traces could occur due to lack of or misplacement of stack frame setup code. This patch forces a stack frame to be created before the inline asm code if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the get_user() inline assembly statement. Signed-off-by: Chris J Arges <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Bernd Petrovitsch <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michal Marek <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pedro Alves <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/bc85501f221ee512670797c7f110022e64b12c81.1453405861.git.jpoim...@redhat.com Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/include/asm/uaccess.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index a4a30e4..9bbb3b2 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -179,10 +179,11 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) ({ \ int __ret_gu; \ register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \ + register void *__sp asm(_ASM_SP); \ __chk_user_ptr(ptr); \ might_fault(); \ - asm volatile("call __get_user_%P3" \ - : "=a" (__ret_gu), "=r" (__val_gu) \ + asm volatile("call __get_user_%P4" \ + : "=a" (__ret_gu), "=r" (__val_gu), "+r" (__sp) \ : "0" (ptr), "i" (sizeof(*(ptr)))); \ (x) = (__force __typeof__(*(ptr))) __val_gu; \ __builtin_expect(__ret_gu, 0); \
