diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-01-27 07:11:27 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-01-27 12:03:29 -0500 |
| commit | 158f323b9868b59967ad96957c4ca388161be321 (patch) | |
| tree | 507829772e7f0849038baf503f85fe788b0e4340 /include/net/sock.h | |
| parent | b41fd8fdef5ad4a1dbd2a159714bd4358bb49625 (diff) | |
| download | linux-158f323b9868b59967ad96957c4ca388161be321.tar.gz linux-158f323b9868b59967ad96957c4ca388161be321.tar.xz | |
net: adjust skb->truesize in pskb_expand_head()
Slava Shwartsman reported a warning in skb_try_coalesce(), when we
detect skb->truesize is completely wrong.
In his case, issue came from IPv6 reassembly coping with malicious
datagrams, that forced various pskb_may_pull() to reallocate a bigger
skb->head than the one allocated by NIC driver before entering GRO
layer.
Current code does not change skb->truesize, leaving this burden to
callers if they care enough.
Blindly changing skb->truesize in pskb_expand_head() is not
easy, as some producers might track skb->truesize, for example
in xmit path for back pressure feedback (sk->sk_wmem_alloc)
We can detect the cases where it should be safe to change
skb->truesize :
1) skb is not attached to a socket.
2) If it is attached to a socket, destructor is sock_edemux()
My audit gave only two callers doing their own skb->truesize
manipulation.
I had to remove skb parameter in sock_edemux macro when
CONFIG_INET is not set to avoid a compile error.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Slava Shwartsman <slavash@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/sock.h')
| -rw-r--r-- | include/net/sock.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 7144750d14e5..94e65fd70354 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1534,7 +1534,7 @@ void sock_efree(struct sk_buff *skb); #ifdef CONFIG_INET void sock_edemux(struct sk_buff *skb); #else -#define sock_edemux(skb) sock_efree(skb) +#define sock_edemux sock_efree #endif int sock_setsockopt(struct socket *sock, int level, int op, |