summaryrefslogtreecommitdiffstats
path: root/net/ipv4
diff options
context:
space:
mode:
authorXufeng Zhang <xufeng.zhang@windriver.com>2011-06-21 12:43:40 +0200
committerDavid S. Miller <davem@davemloft.net>2011-06-22 07:34:27 +0200
commit9cfaa8def1c795a512bc04f2aec333b03724ca2e (patch)
tree2c4bff0afe8424472b780a65a8d356db2d62caf4 /net/ipv4
parentipv6/udp: Use the correct variable to determine non-blocking condition (diff)
downloadlinux-9cfaa8def1c795a512bc04f2aec333b03724ca2e.tar.xz
linux-9cfaa8def1c795a512bc04f2aec333b03724ca2e.zip
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/ipv4')
-rw-r--r--net/ipv4/udp.c3
1 files changed, 3 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:
if (noblock)
return -EAGAIN;
+
+ /* starting over for a new packet */
+ msg->msg_flags &= ~MSG_TRUNC;
goto try_again;
}