smb3: do not attempt multichannel to server which does not support it

We were ignoring CAP_MULTI_CHANNEL in the server response - if the server doesn't support multichannel we should not be attempting it. See MS-SMB2 section 3.2.5.2 Reviewed-by: Shyam Prasad N <[email protected]> Reviewed-By: Tom Talpey <[email protected]> Cc: <[email protected]> # v5.8+ Signed-off-by: Steve French <[email protected]>
wafgo · May 8, 2021 · 9c2dc11 · 9c2dc11
1 parent 679971e
commit 9c2dc11
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
@@ -97,6 +97,12 @@ int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 		return 0;
 	}
 
+	if (!(ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
+		cifs_dbg(VFS, "server %s does not support multichannel\n", ses->server->hostname);
+		ses->chan_max = 1;
+		return 0;
+	}
+
 	/*
 	 * Make a copy of the iface list at the time and use that
 	 * instead so as to not hold the iface spinlock for opening