From ad30f3ff3deb4037f2beea15812d01d795f8b3cc Mon Sep 17 00:00:00 2001 From: John David Anglin <dave.anglin@bell.net> Date: Sun, 25 Nov 2012 21:39:00 +0000 Subject: [PATCH] parisc: sigaltstack doesn't round ss.ss_sp as required 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> Signed-off-by: Helge Deller <deller@gmx.de> --- arch/parisc/kernel/signal.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c index 537996955998..fd051705a407 100644 --- a/arch/parisc/kernel/signal.c +++ b/arch/parisc/kernel/signal.c @@ -190,8 +190,10 @@ 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. */ -- GitLab