From: Houcheng Lin <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== commit b51d3fa364885a2c1e1668f88776c67c95291820 upstream. The kernel should reserve enough room in the skb so that the DONE message can always be appended. However, in case of e.g. new attribute erronously not being size-accounted for, __nfulnl_send() will still try to put next nlmsg into this full skbuf, causing the skb to be stuck forever and blocking delivery of further messages. Fix issue by releasing skb immediately after nlmsg_put error and WARN() so we can track down the cause of such size mismatch. [ [email protected]: add tailroom/len info to WARN ] Signed-off-by: Houcheng Lin <[email protected]> Signed-off-by: Florian Westphal <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- net/netfilter/nfnetlink_log.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 39010fc1e9c0..09172d7abee2 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -348,26 +348,25 @@ nfulnl_alloc_skb(u32 peer_portid, unsigned int inst_size, unsigned int pkt_size) return skb; } -static int +static void __nfulnl_send(struct nfulnl_instance *inst) { - int status = -1; - if (inst->qlen > 1) { struct nlmsghdr *nlh = nlmsg_put(inst->skb, 0, 0, NLMSG_DONE, sizeof(struct nfgenmsg), 0); - if (!nlh) + if (WARN_ONCE(!nlh, "bad nlskb size: %u, tailroom %d\n", + inst->skb->len, skb_tailroom(inst->skb))) { + kfree_skb(inst->skb); goto out; + } } - status = nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid, - MSG_DONTWAIT); - + nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid, + MSG_DONTWAIT); +out: inst->qlen = 0; inst->skb = NULL; -out: - return status; } static void -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
