From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 8F8EB1FF13A for ; Wed, 10 Jun 2026 16:01:16 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 11662106E0; Wed, 10 Jun 2026 16:01:16 +0200 (CEST) Message-ID: Date: Wed, 10 Jun 2026 16:00:42 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Beta Subject: Re: [PATCH log-tracker] handle smtp filter message: prevent panicking with non-standard output To: Thomas Lamprecht , pmg-devel@lists.proxmox.com References: <20260610131513.2907268-1-d.csapak@proxmox.com> <8ecd0b57-478d-4d99-ab92-19bcc4b00a3f@proxmox.com> Content-Language: en-US From: Dominik Csapak In-Reply-To: <8ecd0b57-478d-4d99-ab92-19bcc4b00a3f@proxmox.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1781099995618 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.049 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: OCEGUDXSSTOAYZM4QS42MKMKBQFAZJD4 X-Message-ID-Hash: OCEGUDXSSTOAYZM4QS42MKMKBQFAZJD4 X-MailFrom: d.csapak@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox Mail Gateway development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On 6/10/26 3:51 PM, Thomas Lamprecht wrote: > On 10/06/2026 15:15, Dominik Csapak wrote: >> Currently a custom checkscript can print it's output into the syslog >> under the guise of the pmg-smtp-filter unit, so it will picked up >> by the log tracker. In case there is a line with a delimiter and nothing >> after it, every thing before is detected as a qid but the remaining >> message only contains the delimiter. >> >> Prevent the panicking here by checking its length beforehand. >> >> While the real fix is either to prevent custom check scripts to output >> to syslog, or to prefix it with something we can filter away here, >> protecting against malformed output still makes sense. >> >> Signed-off-by: Dominik Csapak >> --- >> src/main.rs | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/src/main.rs b/src/main.rs >> index efdfd30..4787a36 100644 >> --- a/src/main.rs >> +++ b/src/main.rs >> @@ -115,6 +115,11 @@ fn handle_pmg_smtp_filter_message(msg: &[u8], parser: &mut Parser, complete_line >> Some((q, m)) => (q, m), >> None => return, >> }; >> + if data.len() < 2 { >> + // after the QID there is no separator and space, so it can't be a proper smtp-filter >> + // message. It's possibly output from a custom check script or a malformed log line. > > this comment confuses me, reads like a separator and space after a QID > being wrong, but it's what's expected, with the &data[2..]; IMO no comment > would be required, but short one can be fine - will squash that in on applying. ah ok sorry, i wanted to express that this is missing in this branch, so after the length check shows it's shorter > >> + return; >> + } >> // skip ': ' following the QID >> let data = &data[2..]; >> >