linux-kernel - [PATCH v9 07/20] x86/paravirt: Add stack frame dependency to PVOP inline asm calls

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <4646ec1e44b053aada6eaa77bbd7d3bb4554fd2c.1438963009.git.jpoimboe@redhat.com>
Date:	Fri,  7 Aug 2015 11:50:16 -0500
From:	Josh Poimboeuf <jpoimboe@...hat.com>
To:	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>
Cc:	Michal Marek <mmarek@...e.cz>,
	Peter Zijlstra <peterz@...radead.org>,
	Andy Lutomirski <luto@...nel.org>,
	Borislav Petkov <bp@...en8.de>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andi Kleen <andi@...stfloor.org>,
	Pedro Alves <palves@...hat.com>,
	Namhyung Kim <namhyung@...il.com>,
	Bernd Petrovitsch <bernd@...rovitsch.priv.at>, x86@...nel.org,
	live-patching@...r.kernel.org, linux-kernel@...r.kernel.org,
	Jeremy Fitzhardinge <jeremy@...p.org>,
	Chris Wright <chrisw@...s-sol.org>,
	Alok Kataria <akataria@...are.com>,
	Rusty Russell <rusty@...tcorp.com.au>
Subject: [PATCH v9 07/20] x86/paravirt: Add stack frame dependency to PVOP inline asm calls

If a PVOP call macro is inlined at the beginning of a function, gcc can
insert the call instruction before setting up a stack frame, which
breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and
can result in a bad stack trace.

Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the PVOP inline asm
statements.

Signed-off-by: Josh Poimboeuf <jpoimboe@...hat.com>
Cc: Jeremy Fitzhardinge <jeremy@...p.org>
Cc: Chris Wright <chrisw@...s-sol.org>
Cc: Alok Kataria <akataria@...are.com>
Cc: Rusty Russell <rusty@...tcorp.com.au>
---
 arch/x86/include/asm/paravirt_types.h | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index ce029e4..1812294 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -497,8 +497,9 @@ int paravirt_disable_iospace(void);
  * makes sure the incoming and outgoing types are always correct.
  */
 #ifdef CONFIG_X86_32
-#define PVOP_VCALL_ARGS				\
-	unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx
+#define PVOP_VCALL_ARGS							\
+	unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx;	\
+	register void *__sp asm("esp")
 #define PVOP_CALL_ARGS			PVOP_VCALL_ARGS
 
 #define PVOP_CALL_ARG1(x)		"a" ((unsigned long)(x))
@@ -516,9 +517,10 @@ int paravirt_disable_iospace(void);
 #define VEXTRA_CLOBBERS
 #else  /* CONFIG_X86_64 */
 /* [re]ax isn't an arg, but the return val */
-#define PVOP_VCALL_ARGS					\
-	unsigned long __edi = __edi, __esi = __esi,	\
-		__edx = __edx, __ecx = __ecx, __eax = __eax
+#define PVOP_VCALL_ARGS						\
+	unsigned long __edi = __edi, __esi = __esi,		\
+		__edx = __edx, __ecx = __ecx, __eax = __eax;	\
+	register void *__sp asm("rsp")
 #define PVOP_CALL_ARGS		PVOP_VCALL_ARGS
 
 #define PVOP_CALL_ARG1(x)		"D" ((unsigned long)(x))
@@ -557,7 +559,7 @@ int paravirt_disable_iospace(void);
 			asm volatile(pre				\
 				     paravirt_alt(PARAVIRT_CALL)	\
 				     post				\
-				     : call_clbr			\
+				     : "+r" (__sp), call_clbr		\
 				     : paravirt_type(op),		\
 				       paravirt_clobber(clbr),		\
 				       ##__VA_ARGS__			\
@@ -567,7 +569,7 @@ int paravirt_disable_iospace(void);
 			asm volatile(pre				\
 				     paravirt_alt(PARAVIRT_CALL)	\
 				     post				\
-				     : call_clbr			\
+				     : "+r" (__sp), call_clbr		\
 				     : paravirt_type(op),		\
 				       paravirt_clobber(clbr),		\
 				       ##__VA_ARGS__			\
@@ -594,7 +596,7 @@ int paravirt_disable_iospace(void);
 		asm volatile(pre					\
 			     paravirt_alt(PARAVIRT_CALL)		\
 			     post					\
-			     : call_clbr				\
+			     : "+r" (__sp), call_clbr			\
 			     : paravirt_type(op),			\
 			       paravirt_clobber(clbr),			\
 			       ##__VA_ARGS__				\
-- 
2.4.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/