4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
commit 8004c78c68e894e4fd5ac3c22cc22eb7dc24cabc upstream.
Currently we mark MID as malformed if we get an error from server
in a read response. This leads to not properly processing credits
in the readv callback. Fix this by marking such a response as
normal received response and process it appropriately.
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/cifssmb.c | 35 +++++++++++++++++++++++------------
1 file changed, 23 insertions(+), 12 deletions(-)
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1458,18 +1458,26 @@ cifs_discard_remaining_data(struct TCP_S
}
static int
-cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+__cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid,
+ bool malformed)
{
int length;
- struct cifs_readdata *rdata = mid->callback_data;
length = cifs_discard_remaining_data(server);
- dequeue_mid(mid, rdata->result);
+ dequeue_mid(mid, malformed);
mid->resp_buf = server->smallbuf;
server->smallbuf = NULL;
return length;
}
+static int
+cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+ struct cifs_readdata *rdata = mid->callback_data;
+
+ return __cifs_readv_discard(server, mid, rdata->result);
+}
+
int
cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
{
@@ -1511,12 +1519,23 @@ cifs_readv_receive(struct TCP_Server_Inf
return -1;
}
+ /* set up first two iov for signature check and to get credits */
+ rdata->iov[0].iov_base = buf;
+ rdata->iov[0].iov_len = 4;
+ rdata->iov[1].iov_base = buf + 4;
+ rdata->iov[1].iov_len = server->total_read - 4;
+ cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
+ rdata->iov[0].iov_base, rdata->iov[0].iov_len);
+ cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
+ rdata->iov[1].iov_base, rdata->iov[1].iov_len);
+
/* Was the SMB read successful? */
rdata->result = server->ops->map_error(buf, false);
if (rdata->result != 0) {
cifs_dbg(FYI, "%s: server returned error %d\n",
__func__, rdata->result);
- return cifs_readv_discard(server, mid);
+ /* normal error on read response */
+ return __cifs_readv_discard(server, mid, false);
}
/* Is there enough to get to the rest of the READ_RSP header? */
@@ -1560,14 +1579,6 @@ cifs_readv_receive(struct TCP_Server_Inf
server->total_read += length;
}
- /* set up first iov for signature check */
- rdata->iov[0].iov_base = buf;
- rdata->iov[0].iov_len = 4;
- rdata->iov[1].iov_base = buf + 4;
- rdata->iov[1].iov_len = server->total_read - 4;
- cifs_dbg(FYI, "0: iov_base=%p iov_len=%u\n",
- rdata->iov[0].iov_base, server->total_read);
-
/* how much data is in the response? */
#ifdef CONFIG_CIFS_SMB_DIRECT
use_rdma_mr = rdata->mr;
