ksmbd: no response from compound read

[ Upstream commit e202a1e8634b186da38cbbff85382ea2b9e297cf ]

ksmbd doesn't support compound read. If client send read-read in
compound to ksmbd, there can be memory leak from read buffer.
Windows and linux clients doesn't send it to server yet. For now,
No response from compound read. compound read will be supported soon.

Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-21587, ZDI-CAN-21588
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 74c245809772ede5a3f0860b6b722d76f2c8e097..f6fd5cf976a50da2c1744adb4cd1ed5e766c959a 100644 (file)
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -6314,6 +6314,11 @@ int smb2_read(struct ksmbd_work *work)
        unsigned int max_read_size = conn->vals->max_read_size;
 
        WORK_BUFFERS(work, req, rsp);
+       if (work->next_smb2_rcv_hdr_off) {
+               work->send_no_response = 1;
+               err = -EOPNOTSUPP;
+               goto out;
+       }
 
        if (test_share_config_flag(work->tcon->share_conf,
                                   KSMBD_SHARE_FLAG_PIPE)) {