From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Mike Kazantsev , Eric Dumazet , "David S. Miller" Subject: [ 47/66] net: fix secpath kmemleak Date: Wed, 14 Nov 2012 20:10:52 -0800 Message-Id: <20121115040942.526241268@linuxfoundation.org> In-Reply-To: <20121115040939.016421011@linuxfoundation.org> References: <20121115040939.016421011@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 3d861f661006606bf159fd6bd973e83dbf21d0f9 ] Mike Kazantsev found 3.5 kernels and beyond were leaking memory, and tracked the faulty commit to a1c7fff7e18f59e ("net: netdev_alloc_skb() use build_skb()") While this commit seems fine, it uncovered a bug introduced in commit bad43ca8325 ("net: introduce skb_try_coalesce()), in function kfree_skb_partial()"): If head is stolen, we free the sk_buff, without removing references on secpath (skb->sp). So IPsec + IP defrag/reassembly (using skb coalescing), or TCP coalescing could leak secpath objects. Fix this bug by calling skb_release_head_state(skb) to properly release all possible references to linked objects. Reported-by: Mike Kazantsev Signed-off-by: Eric Dumazet Bisected-by: Mike Kazantsev Tested-by: Mike Kazantsev Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/skbuff.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3384,10 +3384,12 @@ EXPORT_SYMBOL(__skb_warn_lro_forwarding) void kfree_skb_partial(struct sk_buff *skb, bool head_stolen) { - if (head_stolen) + if (head_stolen) { + skb_release_head_state(skb); kmem_cache_free(skbuff_head_cache, skb); - else + } else { __kfree_skb(skb); + } } EXPORT_SYMBOL(kfree_skb_partial);