2021-10-02 21:49 GMT+09:00, Ralph Boehme <slow@xxxxxxxxx>: > Am 02.10.21 um 14:45 schrieb Hyunchul Lee: >> Hi Ralph, >> >> 2021년 10월 1일 (금) 오후 9:25, Ralph Boehme <slow@xxxxxxxxx>님이 작성: >>> >>> Note: we already have the same check in is_chained_smb2_message(), but >>> there it >>> only applies to compound requests, so we have to repeat the check here to >>> cover >>> both cases. >>> >>> Cc: Namjae Jeon <linkinjeon@xxxxxxxxxx> >>> Cc: Tom Talpey <tom@xxxxxxxxxx> >>> Cc: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx> >>> Cc: Steve French <smfrench@xxxxxxxxx> >>> Cc: Hyunchul Lee <hyc.lee@xxxxxxxxx> >>> Signed-off-by: Ralph Boehme <slow@xxxxxxxxx> >>> --- >>> fs/ksmbd/smb2misc.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/fs/ksmbd/smb2misc.c b/fs/ksmbd/smb2misc.c >>> index 7ed266eb6c5e..541b39b7a84b 100644 >>> --- a/fs/ksmbd/smb2misc.c >>> +++ b/fs/ksmbd/smb2misc.c >>> @@ -338,6 +338,9 @@ int ksmbd_smb2_check_message(struct ksmbd_work >>> *work) >>> if (check_smb2_hdr(hdr)) >>> return 1; >>> >>> + if (len < sizeof(struct smb2_pdu) - 4) >>> + return 1; >>> + >> >> Do we need this check before accessing any fields of smb2_hdr in >> ksmbd_verify_smb_message()? > > well, my idea was to have the core PDU size checking logic in > ksmbd_smb2_check_message() and ksmbd_verify_smb_message() merely > switches between SMB1/SMB2. Hyunchul pointed out that this header buffer check should be moved to the above check_smb2_hdr(). I think that it should be move to the above ksmbd_smb2_cur_pdu_buflen(). > > -slow > > -- > Ralph Boehme, Samba Team https://samba.org/ > SerNet Samba Team Lead https://sernet.de/en/team-samba >
