Regex errors spam in syslog

Vaporize

This was actually reported before: https://forum.vivaldi.net/topic/46268/ad-blocker-logs-spam-filter-list-regex-errors-in-syslog but that thread went into Archive category without being fixed. It's been over 4 years and syslog is still being constantly spammed with RE2 regex error lines.

10月 11 16:14:50 dell vivaldi-stable[2952]: E0000 00:00:1728634490.263280    2945 re2.cc:237] Error parsing '^https?:\/\/(?!assets|script|static)(?:[0-9a-z]{10,13}|[0-9a-z]{6})\.[0-9A-Za-z.\-_]+\/(?=[0-9a-z+\/...': invalid perl operator: (?!
10月 11 16:14:50 dell vivaldi-stable[2952]: E0000 00:00:1728634490.263305    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?!
10月 11 16:14:50 dell vivaldi-stable[2952]: E0000 00:00:1728634490.274564    2945 re2.cc:237] Error parsing '^https?:\/\/(?!assets|script|static)(?:[0-9a-z]{10,13}|[0-9a-z]{6})\.[0-9A-Za-z.\-_]+\/(?=[0-9a-z+\/...': invalid perl operator: (?!
10月 11 16:14:50 dell vivaldi-stable[2952]: E0000 00:00:1728634490.274758    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?!
10月 11 16:14:58 dell vivaldi-stable[2952]: E0000 00:00:1728634498.603064    2945 re2.cc:237] Error parsing '^https:\/\/[a-z]{5,12}\.com\/[a-z0-9]{1,20}\?[A-Za-z0-9]{15,22}=(?=.*[A-Z])[A-Za-z0-9%]{200,}$': invalid perl operator: (?=
10月 11 16:14:58 dell vivaldi-stable[2952]: E0000 00:00:1728634498.603111    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?=
10月 11 16:14:58 dell vivaldi-stable[2952]: E0000 00:00:1728634498.603759    2945 re2.cc:237] Error parsing '^https?:\/\/(?:[a-z]{2}\.)?[0-9a-z]{5,16}\.[a-z]{3,7}\/[a-z](?=[a-z]{0,25}[0-9A-Z])[0-9a-zA-Z]{3,26}...': invalid perl operator: (?=
10月 11 16:14:58 dell vivaldi-stable[2952]: E0000 00:00:1728634498.603767    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?=
10月 11 16:15:00 dell vivaldi-stable[2952]: E0000 00:00:1728634500.200672    2945 re2.cc:237] Error parsing '^https:\/\/[a-z]{5,12}\.com\/[a-z0-9]{1,20}\?[A-Za-z0-9]{15,22}=(?=.*[A-Z])[A-Za-z0-9%]{200,}$': invalid perl operator: (?=
10月 11 16:15:00 dell vivaldi-stable[2952]: E0000 00:00:1728634500.200686    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?=
10月 11 16:15:00 dell vivaldi-stable[2952]: E0000 00:00:1728634500.201275    2945 re2.cc:237] Error parsing '^https?:\/\/(?:[a-z]{2}\.)?[0-9a-z]{5,16}\.[a-z]{3,7}\/[a-z](?=[a-z]{0,25}[0-9A-Z])[0-9a-zA-Z]{3,26}...': invalid perl operator: (?=
10月 11 16:15:00 dell vivaldi-stable[2952]: E0000 00:00:1728634500.201288    2945 re2.cc:921] Invalid RE2: invalid perl operator: (?=

It's already known that some adblock rules (either in the built-in adblocker or in Adguard or some other extensions) triggers this error, but this seems rather easy to fix: just don't log error for adblocker regex parse errors except for when the rule list is updated.

For a user actively surfing through the Internet, this error triggers thousands - sometimes tens of thousands times a single day. Basically my syslog content is full of it, which makes debugging other things very difficult. It also causes unnecessary disk writes, which in turn could lead to periodic lagging on systems without an SSD.

My environment is Manjaro Linux latest, with Vivaldi latest (currently 6.9.3447.51).

The original thread also contains a workaround but it unfortunately only works for rsyslogd.

Please can we get a fix on this issue?

DoctorG

@Vaporize How was Vivaldi installed?
by Snap, Flatpak, RPM package?

Can you check which of your active block lists is causing this?
Deactivate all.
Test.
Watch syslog
Enable on blocklist
Test.
Watch syslog
And so on until you found the one which causes the issue.

Vaporize

@DoctorG It's installed from extra repo of Manjaro Linux. Just search for Vivaldi in Add/Remove software.

DoctorG

@Vaporize Missed this edit?

Vaporize

@DoctorG In my case it seems to be caused by this list:

which is loaded from https://filters.adtidy.org/extension/ublock/filters/3.txt. Particularly, this line contains the (?= and (?! which showed up in the error log.

But I suspect this is not accurate, since this list also contains these two operators:

I'll do more test some days later and see if I can pin it down to a single list.

DoctorG

@Vaporize said in Regex errors spam in syslog:

I'll do more test some days later and see if I can pin it down to a single list.

When you ave detected the list causing your issue, please report issue to Vivaldi bug tracker. Once that is done, share the bug number (beginning with VB-) you got by bug report mail.
Thanks for helping us making Vivaldi better.