Commit c527c8a7 authored Nov 03, 2008 by Steve French

[CIFS] Can't rely on iov length and base when kernel_recvmsg returns error

When retrying kernel_recvmsg, reset iov_base and iov_len.

Note comment from Sridhar: "In the normal path, iov.iov_len is clearly set to 4. But i think you are
running into a case where kernel_recvmsg() is called via 'goto incomplete_rcv'
It happens if the previous call fails with EAGAIN.
If you want to call recvmsg() after EAGAIN failure, you need to reset iov."

Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

parent a75952b7

fs/cifs/connect.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -417,9 +417,14 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server)
		msleep(1); /* minimum sleep to prevent looping
		allowing socket to clear and app threads to set
		tcpStatus CifsNeedReconnect if server hung */
		if (pdu_length < 4)
		if (pdu_length < 4) {
		iov.iov_base = (4 - pdu_length) +
		(char *)smb_buffer;
		iov.iov_len = pdu_length;
		smb_msg.msg_control = NULL;
		smb_msg.msg_controllen = 0;
		goto incomplete_rcv;
		else
		} else
		continue;
		} else if (length <= 0) {
		if (server->tcpStatus == CifsNew) {