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| author | Xufeng Zhang <xufeng.zhang@windriver.com> | 2011-06-21 10:43:40 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-07-08 23:14:55 -0700 |
| commit | 03f96d9a71e4b181bfd3946c66f7cf611235bbc7 (patch) | |
| tree | 66075a1b677e2c6696c4df28919cadd361b96093 | |
| parent | ecb58722ec1cdd36e177711fe73b718c89ed1a8c (diff) | |
| download | linux-stable-03f96d9a71e4b181bfd3946c66f7cf611235bbc7.tar.gz linux-stable-03f96d9a71e4b181bfd3946c66f7cf611235bbc7.tar.bz2 linux-stable-03f96d9a71e4b181bfd3946c66f7cf611235bbc7.zip | |
udp/recvmsg: Clear MSG_TRUNC flag when starting over for a new packet
[ Upstream commit 9cfaa8def1c795a512bc04f2aec333b03724ca2e ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -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 f87a8eb76f3b..0e33e34e1f74 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1241,6 +1241,9 @@ csum_copy_err: if (noblock) return -EAGAIN; + + /* starting over for a new packet */ + msg->msg_flags &= ~MSG_TRUNC; goto try_again; } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index f3ffc193e9f0..b31a2f347c3c 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -455,6 +455,9 @@ csum_copy_err: if (noblock) return -EAGAIN; + + /* starting over for a new packet */ + msg->msg_flags &= ~MSG_TRUNC; goto try_again; } |