diff options
| author | Juergen Gross <jgross@suse.com> | 2015-08-06 10:04:38 +0200 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2015-08-25 16:57:01 +0200 |
| commit | 8993fe757113915695cdd020447182b33f0889ad (patch) | |
| tree | f286992e35b2f9bb902a3b3d4b855ac96deee5e2 | |
| parent | 62fc7228f8cc8c89ecbd37008a0495ac28e41c5c (diff) | |
x86/ldt: Correct LDT access in single stepping logic
commit 136d9d83c07c5e30ac49fc83b27e8c4842f108fc upstream.
Commit 37868fe113ff ("x86/ldt: Make modify_ldt synchronous")
introduced a new struct ldt_struct anchored at mm->context.ldt.
convert_ip_to_linear() was changed to reflect this, but indexing
into the ldt has to be changed as the pointer is no longer void *.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/1438848278-12906-1-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
| -rw-r--r-- | arch/x86/kernel/step.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/step.c b/arch/x86/kernel/step.c index 6273324186ac..0ccb53a9fcd9 100644 --- a/arch/x86/kernel/step.c +++ b/arch/x86/kernel/step.c @@ -28,11 +28,11 @@ unsigned long convert_ip_to_linear(struct task_struct *child, struct pt_regs *re struct desc_struct *desc; unsigned long base; - seg &= ~7UL; + seg >>= 3; mutex_lock(&child->mm->context.lock); if (unlikely(!child->mm->context.ldt || - (seg >> 3) >= child->mm->context.ldt->size)) + seg >= child->mm->context.ldt->size)) addr = -1L; /* bogus selector, access would fault */ else { desc = &child->mm->context.ldt->entries[seg]; |