The corresponding patch has been merged in the 4.19 branch
and is released as 4.19.29.
commit b4d965a37d89cd8611984ea16c85903d01ac967a
Author: Ronnie Sahlberg <lsahlber@redhat.com>
AuthorDate: Wed Oct 24 11:50:33 2018 +1000
Commit: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CommitDate: Wed Mar 13 14:02:40 2019 -0700
cifs: allow calling SMB2_xxx_free(NULL)
commit 32a1fb36f6e50183871c2c1fcf5493c633e84732 upstream.
Change these free functions to allow passing NULL as the argument and
treat it as a no-op just like free(NULL) would.
Or, if rqst->rq_iov is NULL.
The second scenario could happen for smb2_queryfs() if the call
to SMB2_query_info_init() fails and we go to qfs_exit to clean up
and free all resources.
In that case we have not yet assigned rqst[2].rq_iov and thus
the rq_iov dereference in SMB2_close_free() will cause a NULL pointer
dereference.
[ bp: upstream patch also fixes SMB2_set_info_free which was introduced in 4.20 ]
Fixes: 1eb9fb52040f ("cifs: create SMB2_open_init()/SMB2_open_free() helpers")
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>