4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pavel Shilovsky pshilov@microsoft.com
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@vger.kernel.org Signed-off-by: Pavel Shilovsky pshilov@microsoft.com Reviewed-by: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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;