[BUG] QBittorrent Memory Leak through Web-UI via Nginx

[lflare]

What happened?

Note: this is the weirdest bug I have ever experienced, and I am fresh out of ideas to even know where to begin attempting to fix it.

Steps to reproduce:

1. Install both nginx and qbittorrent-nox of version 4.3.9. Version of qbittorrent does not matter here, I have tested both 4.4.x and 4.3.x
2. Attempt to access qBittorrent via NGINX on a fresh start via `http:///qbittorrent/
3. Watch memory usage of qbittorrent-nox continuously go up
4. Run systemctl restart qbittorrent-nox nginx for a fresh re-test
5. Attempt to access qBittorrent directly via http://<domain>:10588/whateverport
6. Watch memory usage not go up.
7. ???

For some even weirder browser network logs,

Accessing qBittorrent via NGINX	Accessing qBittorrent directly

As you can see, the rid from accessing via NGINX never seems to properly increment past 1, and accessing it directly seems to properly increment it.

Strange right? Well, for an even weirder experience, from step 3, accessing qBittorrent directly after accessing it via nginx stops the memory leaks, and allows for normal access via nginx without fear of memory leak.

Expected results:

For memory leak to not happen.

Swizzin commit

dfc8942

What OS are you using?

Debian 11 (Bullseye)

What architecture is your OS?

amd64

Relevant logs and output

No response

[liaralabs]

We are using the recommended proxy settings here. Though I wonder if this is coming down to http1.1 vs http2

This might be better off reported to this qBittorrent devs, though I'm not seeing such memory issues in a k3s environment with nginx as the ingress point. This is using http/2 as well 😕

I definitely have noticed this issue; however and several other folks have reported (long ago) that this behavior started after an apt update one day

[liaralabs]

If you are still around and experiencing the issue and willing to try something, can you comment out the following directive from /etc/nginx/apps/qbittorrent.conf?

http2_push_preload on; # Enable http2 push

It's the only non-recommended value in the proxy config

[liaralabs]

I've been doing some dev work today and can't currently reproduce this RID issue you noted. My RID are incrementing fine; however the client doesn't have any data in it since it's just a test instance:

[liaralabs]

Just for some folks following on here, some internal chatter seems to indicate this could be an issue with older glibc versions.

This problem doesn't seem to rear its head on newest glibc versions (Debian 12/Ubuntu 22.04) or musl builds.