Possible FD leak in webtorrent stream 1.9.9

[vooon]

Some time ago i have added few remote cameras re-streamed via webtorrent, because I wanted this traffic to avoid VPN. For some time that worked well, but then I started noticing troubles on rx go2rtc instance, when some of that cameras not working.

With 5 this webtorrent streams not connected I ran out of FDs limit in a few hours (tried to go up from 4k to 256k limit nofile). What I see - lots of sockets left open.

Here is normal state (when left only local RTSP streams):

root@go2rtc:~# lsof -p 2936 | wc -l
160

And here about 5 minutes with webtorrent streams:

root@go2rtc:~# lsof -p 12096 | wc -l
401
root@go2rtc:~# lsof -p 12096 | wc -l
447
root@go2rtc:~# lsof -p 12096 | wc -l
548
root@go2rtc:~# lsof -p 12096 | wc -l
690

I see lots of open UDP sockets, example:

go2rtc  12096 go2rtc  12u     IPv4 218029      0t0    TCP 192.168.25.200:34036->hiw-i400-cam20.lan:rtsp (ESTABLISHED)
go2rtc  12096 go2rtc  13u     IPv6 216773      0t0    TCP 192.168.25.200:8555->frigate.lan:36225 (ESTABLISHED)
go2rtc  12096 go2rtc  14u     IPv6 226599      0t0    TCP go2rtc.lan:1984->frigate.lan:37138 (ESTABLISHED)
go2rtc  12096 go2rtc  15u     IPv4 216805      0t0    UDP *:mdns 
go2rtc  12096 go2rtc  16u     IPv4 219405      0t0    UDP *:59873 
go2rtc  12096 go2rtc  17u     IPv4 218095      0t0    UDP *:33639 
go2rtc  12096 go2rtc  18u     IPv4 218094      0t0    UDP *:50066 
go2rtc  12096 go2rtc  19u     IPv6 225671      0t0    TCP go2rtc.lan:1984->frigate.lan:37136 (ESTABLISHED)
go2rtc  12096 go2rtc  20u     IPv4 218772      0t0    UDP *:mdns 
go2rtc  12096 go2rtc  21u     IPv4 219291      0t0    UDP *:mdns 
go2rtc  12096 go2rtc  22u     IPv4 216707      0t0    UDP *:mdns 
go2rtc  12096 go2rtc  23u     IPv4 219293      0t0    UDP *:42843 

Many of which on a random port, but also a lot on mdns:

root@go2rtc:~# lsof -p 12096 | fgrep ':mdns' | wc -l
165
root@go2rtc:~# lsof -p 12096 | fgrep ':mdns' | wc -l
172

Total amount of UDP slowly grows:

root@go2rtc:~# lsof -p 12096 | fgrep 'UDP' | wc -l
1121
root@go2rtc:~# lsof -p 12096 | fgrep 'UDP' | wc -l
1133
root@go2rtc:~# lsof -p 12096 | fgrep 'UDP' | wc -l
1139
root@go2rtc:~# lsof -p 12096 | fgrep 'UDP' | wc -l
1174

TCP also have some slow grow, but here seems some of the sockets were closed:

root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
287
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
293
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
293
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
297
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
299
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
307
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
305
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
301
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
303
root@go2rtc:~# lsof -p 12096 | fgrep 'TCP' | wc -l
303

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Version: 1.9.9 built from source Go: 1.25.0 Arch: x86_64