4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefan Metzmacher <metze@xxxxxxxxx> commit fa8f3a354bb775ec586e4475bcb07f7dece97e0c upstream. Only server which map unknown users to guest will allow access using a non-null LMChallengeResponse. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913 Signed-off-by: Stefan Metzmacher <metze@xxxxxxxxx> Signed-off-by: Steve French <smfrench@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/cifs/sess.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -678,20 +678,24 @@ sess_auth_lanman(struct sess_data *sess_ pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE; - /* no capabilities flags in old lanman negotiation */ - pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE); + if (ses->user_name != NULL) { + /* no capabilities flags in old lanman negotiation */ + pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE); - /* Calculate hash with password and copy into bcc_ptr. - * Encryption Key (stored as in cryptkey) gets used if the - * security mode bit in Negottiate Protocol response states - * to use challenge/response method (i.e. Password bit is 1). - */ - rc = calc_lanman_hash(ses->password, ses->server->cryptkey, - ses->server->sec_mode & SECMODE_PW_ENCRYPT ? - true : false, lnm_session_key); + /* Calculate hash with password and copy into bcc_ptr. + * Encryption Key (stored as in cryptkey) gets used if the + * security mode bit in Negottiate Protocol response states + * to use challenge/response method (i.e. Password bit is 1). + */ + rc = calc_lanman_hash(ses->password, ses->server->cryptkey, + ses->server->sec_mode & SECMODE_PW_ENCRYPT ? + true : false, lnm_session_key); - memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE); - bcc_ptr += CIFS_AUTH_RESP_SIZE; + memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE); + bcc_ptr += CIFS_AUTH_RESP_SIZE; + } else { + pSMB->old_req.PasswordLength = 0; + } /* * can not sign if LANMAN negotiated so no need -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html