fix oops on rmmod capidrv

Fix overwriting the stack with the version string
(it is currently 10 bytes + zero) when unloading the
capidrv module. Safeguard against overwriting it
should the version string grow in the future.

Should fix Kernel Bug Tracker Bug 9696.

Signed-off-by: Gerd v. Egidy <gerd.von.egidy@intra2net.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/isdn/capi/capidrv.c b/drivers/isdn/capi/capidrv.c
index 48c1775ef5b3..cb42b690b45e 100644
--- a/drivers/isdn/capi/capidrv.c
+++ b/drivers/isdn/capi/capidrv.c
@@ -2332,13 +2332,14 @@ static int __init capidrv_init(void)
 
 static void __exit capidrv_exit(void)
 {
-        char rev[10];
+        char rev[32];
         char *p;
 
         if ((p = strchr(revision, ':')) != 0) {
-                strcpy(rev, p + 1);
-                p = strchr(rev, '$');
-                *p = 0;
+                strncpy(rev, p + 1, sizeof(rev));
+                rev[sizeof(rev)-1] = 0;
+                if ((p = strchr(rev, '$')) != 0)
+                        *p = 0;
         } else {
                 strcpy(rev, " ??? ");
         }