From b3b2854dcf704c1db05d897072f98e8b79398af1 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Sun, 16 Aug 2020 23:14:20 +0200 Subject: mptcp: sendmsg: reset iter on error redux This fix wasn't correct: When this function is invoked from the retransmission worker, the iterator contains garbage and resetting it causes a crash. As the work queue should not be performance critical also zero the msghdr struct. Fixes: 35759383133f64d "(mptcp: sendmsg: reset iter on error)" Signed-off-by: Florian Westphal Signed-off-by: David S. Miller --- net/mptcp/protocol.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index c84b4051c2a4..1aad411a0e46 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -740,7 +740,8 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, ret = do_tcp_sendpages(ssk, page, offset, psize, msg->msg_flags | MSG_SENDPAGE_NOTLAST | MSG_DONTWAIT); if (ret <= 0) { - iov_iter_revert(&msg->msg_iter, psize); + if (!retransmission) + iov_iter_revert(&msg->msg_iter, psize); return ret; } @@ -1392,7 +1393,9 @@ static void mptcp_worker(struct work_struct *work) struct mptcp_data_frag *dfrag; u64 orig_write_seq; size_t copied = 0; - struct msghdr msg; + struct msghdr msg = { + .msg_flags = MSG_DONTWAIT, + }; long timeo = 0; lock_sock(sk); @@ -1425,7 +1428,6 @@ static void mptcp_worker(struct work_struct *work) lock_sock(ssk); - msg.msg_flags = MSG_DONTWAIT; orig_len = dfrag->data_len; orig_offset = dfrag->offset; orig_write_seq = dfrag->data_seq; -- cgit v1.2.3