[CIFS] Fix buffer overflow if server sends corrupt response to small
request
In SendReceive() function in transport.c - it memcpy's
message payload into a buffer passed via out_buf param. The function
assumes that all buffers are of size (CIFSMaxBufSize +
MAX_CIFS_HDR_SIZE) , unfortunately it is also called with smaller
(MAX_CIFS_SMALL_BUFFER_SIZE) buffers. There are eight callers
(SMB worker functions) which are primarily affected by this change:
TreeDisconnect, uLogoff, Close, findClose, SetFileSize, SetFileTimes,
Lock and PosixLock
CC: Dave Kleikamp <shaggy@austin.ibm.com>
CC: Przemyslaw Wegrzyn <czajnik@czajsoft.pl>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 899dc60..ed01ef3 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -514,7 +514,7 @@
iov[1].iov_base = str_area;
iov[1].iov_len = count;
rc = SendReceive2(xid, ses, iov, 2 /* num_iovecs */, &resp_buf_type,
- 0 /* not long op */, 1 /* log NT STATUS if any */ );
+ CIFS_STD_OP /* not long */ | CIFS_LOG_ERROR);
/* SMB request buf freed in SendReceive2 */
cFYI(1, ("ssetup rc from sendrecv2 is %d", rc));