diff options
author | Mathias Krause <minipli@googlemail.com> | 2012-09-13 11:41:26 +0000 |
---|---|---|
committer | Willy Tarreau <w@1wt.eu> | 2013-06-10 11:42:53 +0200 |
commit | 30d5e9d86fd710b54d6ec4ab9d38ebc357e10f84 (patch) | |
tree | 624e802febc1ff1953772652fb72f546066a3c57 /net | |
parent | 89cee197c7947e90ae3600553aaa477eac1ee55a (diff) |
xfrm_user: return error pointer instead of NULL
commit 864745d291b5ba80ea0bd0edcbe67273de368836 upstream.
When dump_one_state() returns an error, e.g. because of a too small
buffer to dump the whole xfrm state, xfrm_state_netlink() returns NULL
instead of an error pointer. But its callers expect an error pointer
and therefore continue to operate on a NULL skbuff.
This could lead to a privilege escalation (execution of user code in
kernel context) if the attacker has CAP_NET_ADMIN and is able to map
address 0.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Diffstat (limited to 'net')
-rw-r--r-- | net/xfrm/xfrm_user.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index a8d83c4dbcc6..dff20acdf672 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -647,6 +647,7 @@ static struct sk_buff *xfrm_state_netlink(struct sk_buff *in_skb, { struct xfrm_dump_info info; struct sk_buff *skb; + int err; skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); if (!skb) @@ -657,9 +658,10 @@ static struct sk_buff *xfrm_state_netlink(struct sk_buff *in_skb, info.nlmsg_seq = seq; info.nlmsg_flags = 0; - if (dump_one_state(x, 0, &info)) { + err = dump_one_state(x, 0, &info); + if (err) { kfree_skb(skb); - return NULL; + return ERR_PTR(err); } return skb; |