On Tue, 14 Sep 2010 15:18:32 +0530
Suresh Jayaraman <sjayaraman@xxxxxxx> wrote:
> On 09/13/2010 11:32 PM, Jeff Layton wrote:
> > cifs_get_smb_ses must be called on a server pointer on which it holds an
> > active reference. It first does a search for an existing SMB session. If
> > it finds one, it'll put the server reference and then try to ensure that
> > the negprot is done, etc.
> >
> > If it encounters an error at that point then it'll return an error.
> > There's a potential problem here though. When cifs_get_smb_ses returns
> > an error, the caller will also put the TCP server reference leading to a
> > double-put.
> >
> > Fix this by having cifs_get_smb_ses only put the server reference if
> > it found an existing session that it could use and isn't returning an
> > error.
> >
> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > ---
> > fs/cifs/connect.c | 6 +++---
> > 1 files changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> > index 67dad54..88c84a3 100644
> > --- a/fs/cifs/connect.c
> > +++ b/fs/cifs/connect.c
> > @@ -1706,9 +1706,6 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
> > if (ses) {
> > cFYI(1, "Existing smb sess found (status=%d)", ses->status);
> >
> > - /* existing SMB ses has a server reference already */
> > - cifs_put_tcp_session(server);
> > -
> > mutex_lock(&ses->session_mutex);
> > rc = cifs_negotiate_protocol(xid, ses);
> > if (rc) {
> > @@ -1731,6 +1728,9 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
> > }
> > }
> > mutex_unlock(&ses->session_mutex);
> > +
> > + /* existing SMB ses has a server reference already */
> > + cifs_put_tcp_session(server);
> > FreeXid(xid);
> > return ses;
> > }
>
> Looks correct to me.
>
> Reviewed-by: Suresh Jayaraman <sjayaraman@xxxxxxx>
Thanks. In hindsight, I should have probably sent this to stable too.
Steve, would you like me to resend and cc stable? We probably want this
in 2.6.36 too, if possible.
--
Jeff Layton <jlayton@xxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
