diff options
author | Jesper Juhl <jesper.juhl@gmail.com> | 2006-12-08 05:39:34 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-08 11:29:01 -0500 |
commit | f6e2cdc8aa395ea813603bfd81b70b5c461a8ebf (patch) | |
tree | cc6c66b9b53bfd313114c4b464223bef992449b4 /drivers/isdn | |
parent | ba6d14aff4112b9518856d2d3979a386cb3a2945 (diff) |
[PATCH] ISDN: Avoid a potential NULL ptr deref in ippp
There's a potential problem in isdn_ppp.c::isdn_ppp_decompress().
dev_alloc_skb() may fail and return NULL. If it does we will be passing a
NULL skb_out to ipc->decompress() and may also end up
dereferencing a NULL pointer at
*proto = isdn_ppp_strip_proto(skb_out);
Correct this by testing 'skb_out' against NULL early and bail out.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/isdn')
-rw-r--r-- | drivers/isdn/i4l/isdn_ppp.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c index 175199088bf4..26e46720fc1c 100644 --- a/drivers/isdn/i4l/isdn_ppp.c +++ b/drivers/isdn/i4l/isdn_ppp.c | |||
@@ -2536,6 +2536,11 @@ static struct sk_buff *isdn_ppp_decompress(struct sk_buff *skb,struct ippp_struc | |||
2536 | rsparm.maxdlen = IPPP_RESET_MAXDATABYTES; | 2536 | rsparm.maxdlen = IPPP_RESET_MAXDATABYTES; |
2537 | 2537 | ||
2538 | skb_out = dev_alloc_skb(is->mru + PPP_HDRLEN); | 2538 | skb_out = dev_alloc_skb(is->mru + PPP_HDRLEN); |
2539 | if (!skb_out) { | ||
2540 | kfree_skb(skb); | ||
2541 | printk(KERN_ERR "ippp: decomp memory allocation failure\n"); | ||
2542 | return NULL; | ||
2543 | } | ||
2539 | len = ipc->decompress(stat, skb, skb_out, &rsparm); | 2544 | len = ipc->decompress(stat, skb, skb_out, &rsparm); |
2540 | kfree_skb(skb); | 2545 | kfree_skb(skb); |
2541 | if (len <= 0) { | 2546 | if (len <= 0) { |