From d5812a77e5803468a5033be91af978be0f7a17d9 Mon Sep 17 00:00:00 2001
From: Paul Mackerras <paulus@samba.org>
Date: Sun, 1 May 2005 08:58:42 -0700
Subject: [PATCH] [PATCH] ppc32: Fix address checking on lmw/stmw align
 exception

The handling of misaligned load/store multiple instructions did not check
to see if the address was ok to access before using __{get,put}_user().

Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 arch/ppc/kernel/align.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/ppc/kernel/align.c b/arch/ppc/kernel/align.c
index 40d356c66c4..ff81da9598d 100644
--- a/arch/ppc/kernel/align.c
+++ b/arch/ppc/kernel/align.c
@@ -290,6 +290,10 @@ fix_alignment(struct pt_regs *regs)
 			/* lwm, stmw */
 			nb = (32 - reg) * 4;
 		}
+
+		if (!access_ok((flags & ST? VERIFY_WRITE: VERIFY_READ), addr, nb+nb0))
+			return -EFAULT;	/* bad address */
+
 		rptr = (unsigned char *) &regs->gpr[reg];
 		if (flags & LD) {
 			for (i = 0; i < nb; ++i)
-- 
2.20.1