From c8884edd078748905552d667857259e5358e1232 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Sun, 29 Oct 2006 15:59:41 -0800 Subject: [PATCH] [NET]: Fix segmentation of linear packets skb_segment fails to segment linear packets correctly because it tries to write all linear parts of the original skb into each segment. This will always panic as each segment only contains enough space for one MSS. This was not detected earlier because linear packets should be rare for GSO. In fact it still remains to be seen what exactly created the linear packets that triggered this bug. Basically the only time this should happen is if someone enables GSO emulation on an interface that does not support SG. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/core/skbuff.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 3c23760c5827..f735455dc5d1 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1946,7 +1946,7 @@ struct sk_buff *skb_segment(struct sk_buff *skb, int features) do { struct sk_buff *nskb; skb_frag_t *frag; - int hsize, nsize; + int hsize; int k; int size; @@ -1957,11 +1957,10 @@ struct sk_buff *skb_segment(struct sk_buff *skb, int features) hsize = skb_headlen(skb) - offset; if (hsize < 0) hsize = 0; - nsize = hsize + doffset; - if (nsize > len + doffset || !sg) - nsize = len + doffset; + if (hsize > len || !sg) + hsize = len; - nskb = alloc_skb(nsize + headroom, GFP_ATOMIC); + nskb = alloc_skb(hsize + doffset + headroom, GFP_ATOMIC); if (unlikely(!nskb)) goto err; -- 2.20.1