ksmbd: fix uaf in smb20_oplock_break_ack

commit c69813471a1ec081a0b9bf0c6bd7e8afd818afce upstream.

drop reference after use opinfo.

Signed-off-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index f6fd5cf976a50da2c1744adb4cd1ed5e766c959a..683152007566c90ebbd7a57afe8ae0abce926c2c 100644 (file)
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -8128,10 +8128,10 @@ static void smb20_oplock_break_ack(struct ksmbd_work *work)
                goto err_out;
        }
 
-       opinfo_put(opinfo);
-       ksmbd_fd_put(work, fp);
        opinfo->op_state = OPLOCK_STATE_NONE;
        wake_up_interruptible_all(&opinfo->oplock_q);
+       opinfo_put(opinfo);
+       ksmbd_fd_put(work, fp);
 
        rsp->StructureSize = cpu_to_le16(24);
        rsp->OplockLevel = rsp_oplevel;