| Message ID | 1347652712-14584-1-git-send-email-minipli@googlemail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Fri, Sep 14, 2012 at 09:58:32PM +0200, Mathias Krause wrote: > When dump_one_policy() returns an error, e.g. because of a too small > buffer to dump the whole xfrm policy, xfrm_policy_netlink() returns > NULL instead of an error pointer. But its caller expects an error > pointer and therefore continues to operate on a NULL skbuff. > > Cc: stable@vger.kernel.org > Signed-off-by: Mathias Krause <minipli@googlemail.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Steffen Klassert <steffen.klassert@secunet.com> Date: Mon, 17 Sep 2012 09:18:53 +0200 > On Fri, Sep 14, 2012 at 09:58:32PM +0200, Mathias Krause wrote: >> When dump_one_policy() returns an error, e.g. because of a too small >> buffer to dump the whole xfrm policy, xfrm_policy_netlink() returns >> NULL instead of an error pointer. But its caller expects an error >> pointer and therefore continues to operate on a NULL skbuff. >> >> Cc: stable@vger.kernel.org >> Signed-off-by: Mathias Krause <minipli@googlemail.com> > > Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Applied and queued up for -stable. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index dac08e2..d12b625 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1548,6 +1548,7 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb, { struct xfrm_dump_info info; struct sk_buff *skb; + int err; skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!skb) @@ -1558,9 +1559,10 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb, info.nlmsg_seq = seq; info.nlmsg_flags = 0; - if (dump_one_policy(xp, dir, 0, &info) < 0) { + err = dump_one_policy(xp, dir, 0, &info); + if (err) { kfree_skb(skb); - return NULL; + return ERR_PTR(err); } return skb;
When dump_one_policy() returns an error, e.g. because of a too small buffer to dump the whole xfrm policy, xfrm_policy_netlink() returns NULL instead of an error pointer. But its caller expects an error pointer and therefore continues to operate on a NULL skbuff. Cc: stable@vger.kernel.org Signed-off-by: Mathias Krause <minipli@googlemail.com> --- Note, this is a different, but similar issue as my previous patch with the almost same subject. I'm not aware of a way how to exploit this bug as the policy *should* always fit into the netlink buffer but better safe then sorry, so cc stable. net/xfrm/xfrm_user.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)