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@davemloft.net>
This commit is contained in:
David S. Miller 2008-08-07 23:04:37 -07:00
parent 764f2579d9
commit 433c5f7068
1 changed files with 4 additions and 2 deletions

View File

@ -26,13 +26,15 @@ 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;