diff options
| author | Konstantin Khlebnikov <koct9i@gmail.com> | 2016-01-08 15:21:46 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-01-15 14:35:24 -0500 |
| commit | 9207f9d45b0ad071baa128e846d7e7ed85016df3 (patch) | |
| tree | 9053fd455c6a19176174674e898ee05c37724827 /net/core | |
| parent | 5d19c619ab3f0551864684f09c2a2f22ee972bef (diff) | |
net: preserve IP control block during GSO segmentation
Skb_gso_segment() uses skb control block during segmentation.
This patch adds 32-bytes room for previous control block which
will be copied into all resulting segments.
This patch fixes kernel crash during fragmenting forwarded packets.
Fragmentation requires valid IP CB in skb for clearing ip options.
Also patch removes custom save/restore in ovs code, now it's redundant.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/dev.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 0ca95d5d7af0..cc9e3652cf93 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2695,6 +2695,8 @@ static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) * * It may return NULL if the skb requires no segmentation. This is * only possible when GSO is used for verifying header integrity. + * + * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb. */ struct sk_buff *__skb_gso_segment(struct sk_buff *skb, netdev_features_t features, bool tx_path) @@ -2709,6 +2711,9 @@ struct sk_buff *__skb_gso_segment(struct sk_buff *skb, return ERR_PTR(err); } + BUILD_BUG_ON(SKB_SGO_CB_OFFSET + + sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); + SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); SKB_GSO_CB(skb)->encap_level = 0; |