FAILED: patch "[PATCH] CIFS: Reconnect expired SMB sessions" failed to apply to 4.9-stable tree

PATCH [email protected] 1 participant 1 message Jul 25, 2017 Stable branch

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[email protected]

author maintainer

2017-07-25 01:22 UTC #0 lore raw

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From 511c54a2f69195b28afb9dd119f03787b1625bb4 Mon Sep 17 00:00:00 2001

From: Pavel Shilovsky <[email protected]>
Date: Sat, 8 Jul 2017 14:32:00 -0700
Subject: [PATCH] CIFS: Reconnect expired SMB sessions

According to the MS-SMB2 spec (3.2.5.1.6) once the client receives STATUS_NETWORK_SESSION_EXPIRED error code from a server it should reconnect the current SMB session. Currently the client doesn't do that. This can result in subsequent client requests failing by the server. The patch adds an additional logic to the demultiplex thread to identify expired sessions and reconnect them.

Cc <[email protected]>

Signed-off-by Pavel Shilovsky <[email protected]>

Signed-off-by Steve French <[email protected]>

fs/cifs/cifsglob.h +2 -0

index bcc7d9acad64..fb482515a64b 100644
@@ -367,6 +367,8 @@ struct smb_version_operations {
 	unsigned int (*calc_smb_size)(void *);
 	/* check for STATUS_PENDING and process it in a positive case */
 	bool (*is_status_pending)(char *, struct TCP_Server_Info *, int);
+	/* check for STATUS_NETWORK_SESSION_EXPIRED */
+	bool (*is_session_expired)(char *);
 	/* send oplock break response */
 	int (*oplock_response)(struct cifs_tcon *, struct cifs_fid *,
 			       struct cifsInodeInfo *);

fs/cifs/cifssmb.c +7 -0

index fbb0d4cbda41..72a53bd19865 100644
@@ -1460,6 +1460,13 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		return length;
 	server->total_read += length;
 
+	if (server->ops->is_session_expired &&
+	    server->ops->is_session_expired(buf)) {
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return -1;
+	}
+
 	if (server->ops->is_status_pending &&
 	    server->ops->is_status_pending(buf, server, 0)) {
 		cifs_discard_remaining_data(server);

fs/cifs/connect.c +7 -0

index 9365c0cf77ad..c59d77f64f74 100644
@@ -812,6 +812,13 @@ cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		cifs_dump_mem("Bad SMB: ", buf,
 			min_t(unsigned int, server->total_read, 48));
 
+	if (server->ops->is_session_expired &&
+	    server->ops->is_session_expired(buf)) {
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return -1;
+	}
+
 	if (server->ops->is_status_pending &&
 	    server->ops->is_status_pending(buf, server, length))
 		return -1;

fs/cifs/smb2ops.c +23 -0

index ed98daa0891c..cfacf2c97e94 100644
@@ -1036,6 +1036,18 @@ smb2_is_status_pending(char *buf, struct TCP_Server_Info *server, int length)
 	return true;
 }
 
+static bool
+smb2_is_session_expired(char *buf)
+{
+	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+
+	if (shdr->Status != STATUS_NETWORK_SESSION_EXPIRED)
+		return false;
+
+	cifs_dbg(FYI, "Session expired\n");
+	return true;
+}
+
 static int
 smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
 		     struct cifsInodeInfo *cinode)

@@ -2217,6 +2229,13 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 		return -ENOTSUPP;
 	}
 
+	if (server->ops->is_session_expired &&
+	    server->ops->is_session_expired(buf)) {
+		cifs_reconnect(server);
+		wake_up(&server->response_q);
+		return -1;
+	}
+
 	if (server->ops->is_status_pending &&
 			server->ops->is_status_pending(buf, server, 0))
 		return -1;

@@ -2534,6 +2553,7 @@ struct smb_version_operations smb20_operations = {
 	.close_dir = smb2_close_dir,
 	.calc_smb_size = smb2_calc_size,
 	.is_status_pending = smb2_is_status_pending,
+	.is_session_expired = smb2_is_session_expired,
 	.oplock_response = smb2_oplock_response,
 	.queryfs = smb2_queryfs,
 	.mand_lock = smb2_mand_lock,

@@ -2622,6 +2642,7 @@ struct smb_version_operations smb21_operations = {
 	.close_dir = smb2_close_dir,
 	.calc_smb_size = smb2_calc_size,
 	.is_status_pending = smb2_is_status_pending,
+	.is_session_expired = smb2_is_session_expired,
 	.oplock_response = smb2_oplock_response,
 	.queryfs = smb2_queryfs,
 	.mand_lock = smb2_mand_lock,

@@ -2712,6 +2733,7 @@ struct smb_version_operations smb30_operations = {
 	.close_dir = smb2_close_dir,
 	.calc_smb_size = smb2_calc_size,
 	.is_status_pending = smb2_is_status_pending,
+	.is_session_expired = smb2_is_session_expired,
 	.oplock_response = smb2_oplock_response,
 	.queryfs = smb2_queryfs,
 	.mand_lock = smb2_mand_lock,

@@ -2812,6 +2834,7 @@ struct smb_version_operations smb311_operations = {
 	.close_dir = smb2_close_dir,
 	.calc_smb_size = smb2_calc_size,
 	.is_status_pending = smb2_is_status_pending,
+	.is_session_expired = smb2_is_session_expired,
 	.oplock_response = smb2_oplock_response,
 	.queryfs = smb2_queryfs,
 	.mand_lock = smb2_mand_lock,