smb3: missing null check in SMB2_change_notify

[ Upstream commit b535cc796a4b4942cd189652588e8d37c1f5925a ]

If plen is null when passed in, we only checked for null
in one of the two places where it could be used. Although
plen is always valid (not null) for current callers of the
SMB2_change_notify function, this change makes it more consistent.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/all/202305251831.3V1gbbFs-lkp@intel.com/
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 02228a590cd5467396b6262993b27cba478a8575..a2a95cd113df8822ff8e6a64cb38e6be784c902b 100644 (file)
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -3777,7 +3777,7 @@ SMB2_change_notify(const unsigned int xid, struct cifs_tcon *tcon,
                if (*out_data == NULL) {
                        rc = -ENOMEM;
                        goto cnotify_exit;
-               } else
+               } else if (plen)
                        *plen = le32_to_cpu(smb_rsp->OutputBufferLength);
        }