diff options
author | Octavian Purdila <opurdila@ixiacom.com> | 2008-06-27 20:27:21 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2008-06-27 20:27:21 -0400 |
commit | db43a282d3ec92ea45109c5551fff3dcc5afef02 (patch) | |
tree | 9104c9559f3bfbdb0868e04a46176989e65c2efa /net | |
parent | 57413ebc4e0f1e471a3b4db4aff9a85c083d090e (diff) |
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>
Diffstat (limited to '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 1e556d31211..366621610e7 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, | |||
1292 | { | 1292 | { |
1293 | unsigned int nr_pages = spd->nr_pages; | 1293 | unsigned int nr_pages = spd->nr_pages; |
1294 | unsigned int poff, plen, len, toff, tlen; | 1294 | unsigned int poff, plen, len, toff, tlen; |
1295 | int headlen, seg; | 1295 | int headlen, seg, error = 0; |
1296 | 1296 | ||
1297 | toff = *offset; | 1297 | toff = *offset; |
1298 | tlen = *total_len; | 1298 | tlen = *total_len; |
1299 | if (!tlen) | 1299 | if (!tlen) { |
1300 | error = 1; | ||
1300 | goto err; | 1301 | goto err; |
1302 | } | ||
1301 | 1303 | ||
1302 | /* | 1304 | /* |
1303 | * if the offset is greater than the linear part, go directly to | 1305 | * 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, | |||
1339 | * just jump directly to update and return, no point | 1341 | * just jump directly to update and return, no point |
1340 | * in going over fragments when the output is full. | 1342 | * in going over fragments when the output is full. |
1341 | */ | 1343 | */ |
1342 | if (spd_fill_page(spd, virt_to_page(p), plen, poff, skb)) | 1344 | error = spd_fill_page(spd, virt_to_page(p), plen, poff, skb); |
1345 | if (error) | ||
1343 | goto done; | 1346 | goto done; |
1344 | 1347 | ||
1345 | tlen -= plen; | 1348 | tlen -= plen; |
@@ -1369,7 +1372,8 @@ map_frag: | |||
1369 | if (!plen) | 1372 | if (!plen) |
1370 | break; | 1373 | break; |
1371 | 1374 | ||
1372 | if (spd_fill_page(spd, f->page, plen, poff, skb)) | 1375 | error = spd_fill_page(spd, f->page, plen, poff, skb); |
1376 | if (error) | ||
1373 | break; | 1377 | break; |
1374 | 1378 | ||
1375 | tlen -= plen; | 1379 | tlen -= plen; |
@@ -1382,7 +1386,10 @@ done: | |||
1382 | return 0; | 1386 | return 0; |
1383 | } | 1387 | } |
1384 | err: | 1388 | err: |
1385 | return 1; | 1389 | /* update the offset to reflect the linear part skip, if any */ |
1390 | if (!error) | ||
1391 | *offset = toff; | ||
1392 | return error; | ||
1386 | } | 1393 | } |
1387 | 1394 | ||
1388 | /* | 1395 | /* |