From: Namjae Jeon <linkinjeon@kernel.org>
Date: Fri, 21 Jul 2023 15:09:28 +0000 (+0900)
Subject: ksmbd: fix out of bounds in smb3_decrypt_req()
X-Git-Tag: v6.4.16~719
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=af4ea4a6842e5e7e1e83a973e5d8e526bbc92d7f;p=thirdparty%2Fkernel%2Fstable.git

ksmbd: fix out of bounds in smb3_decrypt_req()

[ Upstream commit dc318846f3dd54574a36ae97fc8d8b75dd7cdb1e ]

smb3_decrypt_req() validate if pdu_length is smaller than
smb2_transform_hdr size.

Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-21589
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 6d0896c76b098..dab4c7d710914 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -8623,7 +8623,8 @@ int smb3_decrypt_req(struct ksmbd_work *work)
 	struct smb2_transform_hdr *tr_hdr = smb2_get_msg(buf);
 	int rc = 0;
 
-	if (buf_data_size < sizeof(struct smb2_hdr)) {
+	if (pdu_length < sizeof(struct smb2_transform_hdr) ||
+	    buf_data_size < sizeof(struct smb2_hdr)) {
 		pr_err("Transform message is too small (%u)\n",
 		       pdu_length);
 		return -ECONNABORTED;