diff options
| author | Xufeng Zhang <xufeng.zhang@windriver.com> | 2011-06-21 10:43:40 +0000 |
|---|---|---|
| committer | Andi Kleen <ak@linux.intel.com> | 2011-08-01 13:54:59 -0700 |
| commit | cc51d661483c95a61b5385e70e56af019059bde8 (patch) | |
| tree | 55dc62eeb60cbc3f9c48f03917f1e2ae31974325 /net | |
| parent | f5e8deec38218b6c2c20b546dd7727640d68d8f5 (diff) | |
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>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
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 f0fbbba1d203..43536dc8b954 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1206,6 +1206,9 @@ 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 e49cf67506e8..af1a88502d07 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -447,6 +447,9 @@ csum_copy_err: if (noblock) return -EAGAIN; + + /* starting over for a new packet */ + msg->msg_flags &= ~MSG_TRUNC; goto try_again; } |