lkml.org 
[lkml]   [2015]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.12 162/176] x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs
Date
From: Andy Lutomirski <luto@amacapital.net>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 7ddc6a2199f1da405a2fb68c40db8899b1a8cd87 upstream.

These functions can be executed on the int3 stack, so kprobes
are dangerous. Tracing is probably a bad idea, too.

Fixes: b645af2d5905 ("x86_64, traps: Rework bad_iret")
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/50e33d26adca60816f3ba968875801652507d0c4.1416870125.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.10:
- Use __kprobes instead of NOKPROBE_SYMBOL()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/kernel/traps.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 5739ab5359a3..88f3d3b86802 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -369,7 +369,7 @@ exit:
* for scheduling or signal handling. The actual stack switch is done in
* entry.S
*/
-asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
+asmlinkage notrace __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
{
struct pt_regs *regs = eregs;
/* Did already sync */
@@ -394,7 +394,7 @@ struct bad_iret_stack {
struct pt_regs regs;
};

-asmlinkage __visible
+asmlinkage __visible notrace __kprobes
struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s)
{
/*
--
2.2.2


\
 
 \ /
  Last update: 2015-01-29 11:41    [W:0.579 / U:2.188 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site