| Message ID | CANT5p=pqb7MmFe+kQU67Eytm98tZB1ztr0d5Rwq44oxAq81+Dw@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | cifs: add server conn_id to fscache client cookie | expand |
Added fix for problem (missing ifdef) pointed out by kernel test robot +#ifdef CONFIG_CIFS_FSCACHE + else + tcp_ses->fscache = tcp_ses->primary_server->fscache; +#endif /* CONFIG_CIFS_FSCACHE */ See attached On Fri, Dec 3, 2021 at 3:28 AM Shyam Prasad N <nspmangalore@gmail.com> wrote: > > The fscache client cookie uses the server address > (and port) as the cookie key. This is a problem when > nosharesock is used. Two different connections will > use duplicate cookies. Avoid this by adding > server->conn_id to the key, so that it's guaranteed > that cookie will not be duplicated. > > Also, for secondary channels of a session, copy the > fscache pointer from the primary channel. The primary > channel is guaranteed not to go away as long as secondary > channels are in use. > > Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> > --- > fs/cifs/connect.c | 2 ++ > fs/cifs/fscache.c | 10 ++++++++++ > 2 files changed, 12 insertions(+) > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > index eee994b0925f..d8822e835cc4 100644 > --- a/fs/cifs/connect.c > +++ b/fs/cifs/connect.c > @@ -1562,6 +1562,8 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx, > /* fscache server cookies are based on primary channel only */ > if (!CIFS_SERVER_IS_CHAN(tcp_ses)) > cifs_fscache_get_client_cookie(tcp_ses); > + else > + tcp_ses->fscache = tcp_ses->primary_server->fscache; > > /* queue echo request delayed work */ > queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval); > diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c > index f4da693760c1..1db3437f3b7d 100644 > --- a/fs/cifs/fscache.c > +++ b/fs/cifs/fscache.c > @@ -24,6 +24,7 @@ struct cifs_server_key { > struct in_addr ipv4_addr; > struct in6_addr ipv6_addr; > }; > + __u64 conn_id; > } __packed; > > /* > @@ -37,6 +38,14 @@ void cifs_fscache_get_client_cookie(struct > TCP_Server_Info *server) > struct cifs_server_key key; > uint16_t key_len = sizeof(key.hdr); > > + /* > + * Check if cookie was already initialized so don't reinitialize it. > + * In the future, as we integrate with newer fscache features, > + * we may want to instead add a check if cookie has changed > + */ > + if (server->fscache) > + return; > + > memset(&key, 0, sizeof(key)); > > /* > @@ -62,6 +71,7 @@ void cifs_fscache_get_client_cookie(struct > TCP_Server_Info *server) > server->fscache = NULL; > return; > } > + key.conn_id = server->conn_id; > > server->fscache = > fscache_acquire_cookie(cifs_fscache_netfs.primary_index,
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index eee994b0925f..d8822e835cc4 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1562,6 +1562,8 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx, /* fscache server cookies are based on primary channel only */ if (!CIFS_SERVER_IS_CHAN(tcp_ses)) cifs_fscache_get_client_cookie(tcp_ses); + else + tcp_ses->fscache = tcp_ses->primary_server->fscache; /* queue echo request delayed work */ queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval); diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c index f4da693760c1..1db3437f3b7d 100644 --- a/fs/cifs/fscache.c +++ b/fs/cifs/fscache.c @@ -24,6 +24,7 @@ struct cifs_server_key { struct in_addr ipv4_addr; struct in6_addr ipv6_addr; }; + __u64 conn_id; } __packed; /* @@ -37,6 +38,14 @@ void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) struct cifs_server_key key; uint16_t key_len = sizeof(key.hdr); + /* + * Check if cookie was already initialized so don't reinitialize it. + * In the future, as we integrate with newer fscache features, + * we may want to instead add a check if cookie has changed + */ + if (server->fscache) + return; + memset(&key, 0, sizeof(key));
The fscache client cookie uses the server address (and port) as the cookie key. This is a problem when nosharesock is used. Two different connections will use duplicate cookies. Avoid this by adding server->conn_id to the key, so that it's guaranteed that cookie will not be duplicated. Also, for secondary channels of a session, copy the fscache pointer from the primary channel. The primary channel is guaranteed not to go away as long as secondary channels are in use. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> --- fs/cifs/connect.c | 2 ++ fs/cifs/fscache.c | 10 ++++++++++ 2 files changed, 12 insertions(+) /* @@ -62,6 +71,7 @@ void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) server->fscache = NULL; return; } + key.conn_id = server->conn_id; server->fscache = fscache_acquire_cookie(cifs_fscache_netfs.primary_index,