From 7a77dd0168e94667ca4f44a33721380dfc1fd104 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 22 Oct 2012 09:03:40 +0000 Subject: [PATCH] net: fix secpath kmemleak [ 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(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index ef172afd3a8b..97087775b1b3 100644 --- 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); -- 2.39.5