From 433c5f706856689be25928a99636e724fb3ea7cf Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 7 Aug 2008 23:04:37 -0700 Subject: [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 --- arch/sparc64/kernel/stacktrace.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/sparc64/kernel/stacktrace.c b/arch/sparc64/kernel/stacktrace.c index b3e3737750d..e9d7f0660f2 100644 --- a/arch/sparc64/kernel/stacktrace.c +++ b/arch/sparc64/kernel/stacktrace.c @@ -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; -- 2.41.1