Hexagon: check to if we will overflow the signal stack
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
diff --git a/arch/hexagon/kernel/signal.c b/arch/hexagon/kernel/signal.c
index 8a20e8e..097623c 100644
--- a/arch/hexagon/kernel/signal.c
+++ b/arch/hexagon/kernel/signal.c
@@ -41,6 +41,10 @@
{
unsigned long sp = regs->r29;
+ /* check if we would overflow the alt stack */
+ if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
+ return (void __user __force *)-1UL;
+
/* Switch to signal stack if appropriate */
if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
sp = current->sas_ss_sp + current->sas_ss_size;