x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs

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

Fixes: b645af2d59 ("x86_64, traps: Rework bad_iret")
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: <stable@vger.kernel.org> # Backport as far back as it would apply
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>
This commit is contained in:
Andy Lutomirski 2014-11-24 17:39:06 -08:00 committed by Ingo Molnar
parent 5d01410fe4
commit 7ddc6a2199

View file

@ -387,7 +387,7 @@ NOKPROBE_SYMBOL(do_int3);
* for scheduling or signal handling. The actual stack switch is done in
* entry.S
*/
asmlinkage __visible struct pt_regs *sync_regs(struct pt_regs *eregs)
asmlinkage __visible notrace struct pt_regs *sync_regs(struct pt_regs *eregs)
{
struct pt_regs *regs = eregs;
/* Did already sync */
@ -413,7 +413,7 @@ struct bad_iret_stack {
struct pt_regs regs;
};
asmlinkage __visible
asmlinkage __visible notrace
struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s)
{
/*
@ -436,6 +436,7 @@ struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s)
BUG_ON(!user_mode_vm(&new_stack->regs));
return new_stack;
}
NOKPROBE_SYMBOL(fixup_bad_iret);
#endif
/*