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| author | Jesper Juhl <jj@chaosbits.net> | 2011-07-29 16:38:49 +0200 |
|---|---|---|
| committer | Patrick McHardy <kaber@trash.net> | 2011-07-29 16:38:49 +0200 |
| commit | 91c66c6893a3e2bb8a88a30cb76007d5d49d32c9 (patch) | |
| tree | 1f37d40b668d46f305dd9088737c72ece4a91533 /net | |
| parent | 00fe1ae91e0d69e52e8212d23cd3ecc74a7259a0 (diff) | |
| download | linux-91c66c6893a3e2bb8a88a30cb76007d5d49d32c9.tar.gz linux-91c66c6893a3e2bb8a88a30cb76007d5d49d32c9.tar.bz2 linux-91c66c6893a3e2bb8a88a30cb76007d5d49d32c9.zip | |
netfilter: ip_queue: Fix small leak in ipq_build_packet_message()
ipq_build_packet_message() in net/ipv4/netfilter/ip_queue.c and
net/ipv6/netfilter/ip6_queue.c contain a small potential mem leak as
far as I can tell.
We allocate memory for 'skb' with alloc_skb() annd then call
nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
NLMSG_PUT is a macro
NLMSG_PUT(skb, pid, seq, type, len) \
NLMSG_NEW(skb, pid, seq, type, len, 0)
that expands to NLMSG_NEW, which is also a macro which expands to:
NLMSG_NEW(skb, pid, seq, type, len, flags) \
({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
goto nlmsg_failure; \
__nlmsg_put(skb, pid, seq, type, len, flags); })
If we take the true branch of the 'if' statement and 'goto
nlmsg_failure', then we'll, at that point, return from
ipq_build_packet_message() without having assigned 'skb' to anything
and we'll leak the memory we allocated for it when it goes out of
scope.
Fix this by placing a 'kfree(skb)' at 'nlmsg_failure'.
I admit that I do not know how likely this to actually happen or even
if there's something that guarantees that it will never happen - I'm
not that familiar with this code, but if that is so, I've not been
able to spot it.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/netfilter/ip_queue.c | 1 | ||||
| -rw-r--r-- | net/ipv6/netfilter/ip6_queue.c | 1 |
2 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c index 5c9b9d963918..48f7d5b4ff37 100644 --- a/net/ipv4/netfilter/ip_queue.c +++ b/net/ipv4/netfilter/ip_queue.c @@ -218,6 +218,7 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp) return skb; nlmsg_failure: + kfree_skb(skb); *errp = -EINVAL; printk(KERN_ERR "ip_queue: error creating packet message\n"); return NULL; diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c index 249394863284..87b243a25afa 100644 --- a/net/ipv6/netfilter/ip6_queue.c +++ b/net/ipv6/netfilter/ip6_queue.c @@ -218,6 +218,7 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp) return skb; nlmsg_failure: + kfree_skb(skb); *errp = -EINVAL; printk(KERN_ERR "ip6_queue: error creating packet message\n"); return NULL; |