diff options
| author | Xufeng Zhang <xufeng.zhang@windriver.com> | 2011-06-21 10:43:40 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-07-13 05:31:27 +0200 |
| commit | fae5c27e842fef2c59ea3ab4a9afaf903cbd267e (patch) | |
| tree | 23e5c831d4381bb9b2662d89b62143c3c3abef27 | |
| parent | 05c824cea44ddb773182ac849276a2e0419e3ab2 (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>
| -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 659f3b2ea85..743a1210ac0 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1203,6 +1203,9 @@ 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 e363c6c76af..3e9969b429b 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -443,6 +443,9 @@ csum_copy_err: if (noblock) return -EAGAIN; + + /* starting over for a new packet */ + msg->msg_flags &= ~MSG_TRUNC; goto try_again; } |