ksmbd: fix possible null-deref in smb_lazy_parent_lease_break_close

rcu_dereference can return NULL, so make sure we check against that.

Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c
index 9af5fd68bd85b45ac1fb6ef9f066a666603ec99b..b30ff8b9777df6e13e3bec298b99ef20d2ef829c 100644 (file)
--- a/fs/smb/server/oplock.c
+++ b/fs/smb/server/oplock.c
@@ -1143,7 +1143,7 @@ void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp)
        opinfo = rcu_dereference(fp->f_opinfo);
        rcu_read_unlock();
 
-       if (!opinfo->is_lease || opinfo->o_lease->version != 2)
+       if (!opinfo || !opinfo->is_lease || opinfo->o_lease->version != 2)
                return;
 
        p_ci = ksmbd_inode_lookup_lock(fp->filp->f_path.dentry->d_parent);