diff mbox

parisc: sigaltstack doesn't round ss.ss_sp as required

Message ID BLU0-SMTP91E4227D7FA649C74A9CB397580@phx.gbl (mailing list archive)
State Superseded
Headers show

Commit Message

John David Anglin Nov. 25, 2012, 9:39 p.m. UTC 
On 24-Nov-12, at 10:05 AM, John David Anglin wrote:

> In trying to build the debian libsigsegv2 package, I found that  
> sigaltstack
> doesn't round ss.ss_sp.  The tests intentionally pass an unaligned  
> pointer.
> This results in the two stack overflow tests failing.


The attached patch fixes this issue.

Signed-off-by: John David Anglin <dave.anglin@bell.net>

--
John David Anglin	dave.anglin@bell.net
diff mbox

Patch

diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
index 594459b..324644d 100644
--- a/arch/parisc/kernel/signal.c
+++ b/arch/parisc/kernel/signal.c
@@ -188,8 +188,10 @@  get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
 	DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
 			(unsigned long)ka, sp, frame_size);
 	
+	/* Align alternate stack and reserve 64 bytes for the signal
+	   handler's frame marker.  */
 	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
-		sp = current->sas_ss_sp; /* Stacks grow up! */
+		sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
 
 	DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
 	return (void __user *) sp; /* Stacks grow up.  Fun. */