diff options
author | Xufeng Zhang <xufeng.zhang@windriver.com> | 2011-06-21 06:43:40 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2011-06-22 01:34:27 -0400 |
commit | 9cfaa8def1c795a512bc04f2aec333b03724ca2e (patch) | |
tree | 2c4bff0afe8424472b780a65a8d356db2d62caf4 /net | |
parent | 32c90254ed4a0c698caa0794ebb4de63fcc69631 (diff) |
udp/recvmsg: Clear MSG_TRUNC flag when starting over for a new packet
Consider this scenario: When the size of the first received udp packet
is bigger than the receive buffer, MSG_TRUNC bit is set in msg->msg_flags.
However, if checksum error happens and this is a blocking socket, it will
goto try_again loop to receive the next packet. But if the size of the
next udp packet is smaller than receive buffer, MSG_TRUNC flag should not
be set, but because MSG_TRUNC bit is not cleared in msg->msg_flags before
receive the next packet, MSG_TRUNC is still set, which is wrong.
Fix this problem by clearing MSG_TRUNC flag when starting over for a
new packet.
Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/ipv4/udp.c | 3 | ||||
-rw-r--r-- | net/ipv6/udp.c | 3 |
2 files changed, 6 insertions, 0 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index abca870d8ff6..48cd88e62553 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c | |||
@@ -1249,6 +1249,9 @@ csum_copy_err: | |||
1249 | 1249 | ||
1250 | if (noblock) | 1250 | if (noblock) |
1251 | return -EAGAIN; | 1251 | return -EAGAIN; |
1252 | |||
1253 | /* starting over for a new packet */ | ||
1254 | msg->msg_flags &= ~MSG_TRUNC; | ||
1252 | goto try_again; | 1255 | goto try_again; |
1253 | } | 1256 | } |
1254 | 1257 | ||
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 1e7a43f500ab..328985c40883 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c | |||
@@ -455,6 +455,9 @@ csum_copy_err: | |||
455 | 455 | ||
456 | if (noblock) | 456 | if (noblock) |
457 | return -EAGAIN; | 457 | return -EAGAIN; |
458 | |||
459 | /* starting over for a new packet */ | ||
460 | msg->msg_flags &= ~MSG_TRUNC; | ||
458 | goto try_again; | 461 | goto try_again; |
459 | } | 462 | } |
460 | 463 | ||