diff options
author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2008-11-24 21:30:21 -0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2008-11-24 21:30:21 -0800 |
commit | 0ace285605314c54339710484b54814945a60df8 (patch) | |
tree | 1bdfab683c0baea4827f0ee465ab9bc2e5833ba9 | |
parent | 111cc8b913b42ef07793648b1699288332f273e1 (diff) |
tcp: handle shift/merge of cloned skbs too
This caused me to get repeatably:
tcpdump: pcap_loop: recvfrom: Bad address
Happens occassionally when I tcpdump my for-looped test xfers:
while [ : ]; do echo -n "$(date '+%s.%N') "; ./sendfile; sleep 20; done
Rest of the relevant commands:
ethtool -K eth0 tso off
tc qdisc add dev eth0 root netem drop 4%
tcpdump -n -s0 -i eth0 -w sacklog.all
Running net-next under kvm, connection goes to the same host
(basically just out of kvm). The connection itself works ok
and data gets sent without corruption even with a large
number of tests while tcpdump fails usually within less than
5 tests.
Whether it only happens because of this change or not, I
don't know for sure but it's the only thing with which
I've seen that error. The non-cloned variant works w/o it
for much longer time. I'm yet to debug where the error
actually comes from.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/core/skbuff.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 844b8abeb18..57555a4525d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2018,13 +2018,10 @@ void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len) skb_split_no_header(skb, skb1, len, pos); } -/* Shifting from/to a cloned skb is a no-go. - * - * TODO: handle cloned skbs by using pskb_expand_head() - */ +/* Shifting from/to a cloned skb is a no-go. */ static int skb_prepare_for_shift(struct sk_buff *skb) { - return skb_cloned(skb); + return skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC); } /** |