| Message ID | 20220913104059.2545304-2-zhangxiaoxu5@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix some bug in FSCTL_VALIDATE_NEGOTIATE_INFO handler | expand |
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,
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> Reviewed-by: Tom Talpey <tom@talpey.com> --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)