From: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Date: Mon, 26 Sep 2022 11:36:29 +0800
Subject: [PATCH] cifs: Fix the error length of VALIDATE_NEGOTIATE_INFO message
Git-commit: e98ecc6e94f4e6d21c06660b0f336df02836694f
References: bsc#1190317
Patch-mainline: v6.1-rc1
Commit d5c7076b772a ("smb3: add smb3.1.1 to default dialect list")
extend the dialects from 3 to 4, but forget to decrease the extended
length when specific the dialect, then the message length is larger
than expected.
This maybe leak some info through network because not initialize the
message body.
After apply this patch, the VALIDATE_NEGOTIATE_INFO message length is
reduced from 28 bytes to 26 bytes.
Fixes: d5c7076b772a ("smb3: add smb3.1.1 to default dialect list")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Cc: <stable@vger.kernel.org>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/smb2pdu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 6352ab32c7e7..223056097b54 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1169,9 +1169,9 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
pneg_inbuf->Dialects[0] =
cpu_to_le16(server->vals->protocol_id);
pneg_inbuf->DialectCount = cpu_to_le16(1);
- /* structure is big enough for 3 dialects, sending only 1 */
+ /* structure is big enough for 4 dialects, sending only 1 */
inbuflen = sizeof(*pneg_inbuf) -
- sizeof(pneg_inbuf->Dialects[0]) * 2;
+ sizeof(pneg_inbuf->Dialects[0]) * 3;
}
rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
--
2.35.3