[PATCH 4.7 077/186] cifs: unbreak TCP session reuse

From: Greg Kroah-Hartman
Date: Thu Aug 18 2016 - 10:12:26 EST


4.7-stable review patch. If anyone has any objections, please let me know.

------------------

From: Rabin Vincent <rabinv@xxxxxxxx>

commit b782fcc1cbeb7e336c0ed1f00004b2208f48ffe0 upstream.

adfeb3e0 ("cifs: Make echo interval tunable") added a comparison of
vol->echo_interval to server->echo_interval as a criterium to
match_server(), but:

(1) A default value is set for server->echo_interval but not for
vol->echo_interval, meaning these can never match if the echo_interval
option is not specified.

(2) vol->echo_interval is in seconds but server->echo_interval is in
jiffies, meaning these can never match even if the echo_interval option
is specified.

This broke TCP session reuse since match_server() can never return 1.
Fix it.

Fixes: adfeb3e0 ("cifs: Make echo interval tunable")
Signed-off-by: Rabin Vincent <rabinv@xxxxxxxx>
Acked-by: Sachin Prabhu <sprabhu@xxxxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/connect.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1228,6 +1228,8 @@ cifs_parse_mount_options(const char *mou
vol->ops = &smb1_operations;
vol->vals = &smb1_values;

+ vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
+
if (!mountdata)
goto cifs_parse_mount_err;

@@ -2049,7 +2051,7 @@ static int match_server(struct TCP_Serve
if (!match_security(server, vol))
return 0;

- if (server->echo_interval != vol->echo_interval)
+ if (server->echo_interval != vol->echo_interval * HZ)
return 0;

return 1;