diff options
| author | Octavian Purdila <opurdila@ixiacom.com> | 2008-06-28 02:27:21 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-06-28 02:27:21 +0200 |
| commit | db43a282d3ec92ea45109c5551fff3dcc5afef02 (patch) | |
| tree | 9104c9559f3bfbdb0868e04a46176989e65c2efa | |
| parent | tcp: calculate tcp_mem based on low memory instead of all memory (diff) | |
| download | linux-db43a282d3ec92ea45109c5551fff3dcc5afef02.tar.xz linux-db43a282d3ec92ea45109c5551fff3dcc5afef02.zip | |
tcp: fix for splice receive when used with software LRO
If an skb has nr_frags set to zero but its frag_list is not empty (as
it can happen if software LRO is enabled), and a previous
tcp_read_sock has consumed the linear part of the skb, then
__skb_splice_bits:
(a) incorrectly reports an error and
(b) forgets to update the offset to account for the linear part
Any of the two problems will cause the subsequent __skb_splice_bits
call (the one that handles the frag_list skbs) to either skip data,
or, if the unadjusted offset is greater then the size of the next skb
in the frag_list, make tcp_splice_read loop forever.
Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/skbuff.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 1e556d312117..366621610e76 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1292,12 +1292,14 @@ static int __skb_splice_bits(struct sk_buff *skb, unsigned int *offset, { unsigned int nr_pages = spd->nr_pages; unsigned int poff, plen, len, toff, tlen; - int headlen, seg; + int headlen, seg, error = 0; toff = *offset; tlen = *total_len; - if (!tlen) + if (!tlen) { + error = 1; goto err; + } /* * if the offset is greater than the linear part, go directly to @@ -1339,7 +1341,8 @@ static int __skb_splice_bits(struct sk_buff *skb, unsigned int *offset, * just jump directly to update and return, no point * in going over fragments when the output is full. */ - if (spd_fill_page(spd, virt_to_page(p), plen, poff, skb)) + error = spd_fill_page(spd, virt_to_page(p), plen, poff, skb); + if (error) goto done; tlen -= plen; @@ -1369,7 +1372,8 @@ map_frag: if (!plen) break; - if (spd_fill_page(spd, f->page, plen, poff, skb)) + error = spd_fill_page(spd, f->page, plen, poff, skb); + if (error) break; tlen -= plen; @@ -1382,7 +1386,10 @@ done: return 0; } err: - return 1; + /* update the offset to reflect the linear part skip, if any */ + if (!error) + *offset = toff; + return error; } /* |