X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=arch%2Fs390%2Fkernel%2Fsignal.c;h=b976820402154a49b3792e7f8c07d7c803416358;hb=996abf053eec4d67136be8b911bbaaf989cfb99c;hp=4449bf32cbf1e976e414518cee77998587ba18a3;hpb=dd07a8db7283f52f347aee468007556944b5b393;p=linux-2.6

diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 4449bf32cb..b976820402 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -27,6 +27,7 @@
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/lowcore.h>
+#include "entry.h"
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
@@ -235,6 +236,10 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
 	/* Default to using normal stack */
 	sp = regs->gprs[15];
 
+	/* Overflow on alternate signal stack gives SIGSEGV. */
+	if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
+		return (void __user *) -1UL;
+
 	/* This is the X/Open sanctioned signal stack switching.  */
 	if (ka->sa.sa_flags & SA_ONSTACK) {
 		if (! sas_ss_flags(sp))
@@ -270,6 +275,9 @@ static int setup_frame(int sig, struct k_sigaction *ka,
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe)))
 		goto give_sigsegv;
 
+	if (frame == (void __user *) -1UL)
+		goto give_sigsegv;
+
 	if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE))
 		goto give_sigsegv;
 
@@ -327,6 +335,9 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe)))
 		goto give_sigsegv;
 
+	if (frame == (void __user *) -1UL)
+		goto give_sigsegv;
+
 	if (copy_siginfo_to_user(&frame->info, info))
 		goto give_sigsegv;
 
@@ -474,11 +485,6 @@ void do_signal(struct pt_regs *regs)
 		int ret;
 #ifdef CONFIG_COMPAT
 		if (test_thread_flag(TIF_31BIT)) {
-			extern int handle_signal32(unsigned long sig,
-						   struct k_sigaction *ka,
-						   siginfo_t *info,
-						   sigset_t *oldset,
-						   struct pt_regs *regs);
 			ret = handle_signal32(signr, &ka, &info, oldset, regs);
 	        }
 		else