From: "Alexander Beregalov" <a.beregalov@xxxxxxxxx>
Date: Mon, 7 Jul 2008 19:59:04 +0400
> I have turned off LOCKDEP and it boots properly.
> 2.6.26-rc9-00005-g1b40a89
>
> Mikael's config also does not contain LOCKDEP.
I have finally reproduced the problem locally and figured out the
bug.
Please try this patch:
sparc64: Fix end-of-stack checking in save_stack_trace().
Bug reported by Alexander Beregalov.
Before we dereference the stack frame or try to peek at the
pt_regs magic value, make sure the entire object is within
the kernel stack bounds.
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
diff --git a/arch/sparc64/kernel/stacktrace.c b/arch/sparc64/kernel/stacktrace.c
index c73ce3f..c5576e8 100644
--- a/arch/sparc64/kernel/stacktrace.c
+++ b/arch/sparc64/kernel/stacktrace.c
@@ -25,13 +25,15 @@ void save_stack_trace(struct stack_trace *trace)
/* Bogus frame pointer? */
if (fp < (thread_base + sizeof(struct thread_info)) ||
- fp >= (thread_base + THREAD_SIZE))
+ fp > (thread_base + THREAD_SIZE - sizeof(struct sparc_stackf)))
break;
sf = (struct sparc_stackf *) fp;
regs = (struct pt_regs *) (sf + 1);
- if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC) {
+ if (((unsigned long)regs <=
+ (thread_base + THREAD_SIZE - sizeof(*regs))) &&
+ (regs->magic & ~0x1ff) == PT_REGS_MAGIC) {
if (!(regs->tstate & TSTATE_PRIV))
break;
pc = regs->tpc;
--
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