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Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Paolo Abeni , Simon Horman , Jason Xing Content-Type: text/plain; charset="UTF-8" skb_copy_ubufs drops clones and modifies the SKB via pskb_expand_head() before checking for !skb_frags_readable(skb). This alters the SKB geometry prior to throwing an -EFAULT on an invalid SKB. Check readability first. Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Signed-off-by: Mina Almasry --- Note to sashiko: if you find pre-existing issues, mark them clearly as pre-existing. --- net/core/skbuff.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d4382b68d56e0..201c9ec1519c7 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2001,12 +2001,12 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) int i, order, psize, new_frags; u32 d_off; - if (skb_shared(skb) || skb_unclone(skb, gfp_mask)) - return -EINVAL; - if (!skb_frags_readable(skb)) return -EFAULT; + if (skb_shared(skb) || skb_unclone(skb, gfp_mask)) + return -EINVAL; + if (!num_frags) goto release; base-commit: 7cbfb180945ce529608e4d4e24a6d483699fab1e -- 2.55.0.766.g2966f0265a-goog