[BUG] ps3netsrv-go can't stat PS3 CHD files from ISOS above 10GB

[kadai]

While I was doing tests for #37 I happened to come across some issues with some PS3 CHD files.

Upon digging more into the logs, I started to see entries like this in my log files:

2026-04-03T20:32:18.306121-05:00 homeserver ps3netsrv-go[152877]: Apr  3 20:32:18.305 DBG Trying opener request_path=PS3ISO// op=readdir opener=viso path="PS3ISO///Bayonetta (USA) (En,Ja,Fr,De,Es,It).chd"
2026-04-03T20:32:18.306258-05:00 homeserver ps3netsrv-go[152877]: Apr  3 20:32:18.305 DBG Trying opener request_path=PS3ISO// op=readdir opener=chd path="PS3ISO///Bayonetta (USA) (En,Ja,Fr,De,Es,It).chd"
2026-04-03T20:32:18.306405-05:00 homeserver ps3netsrv-go[152877]: Apr  3 20:32:18.305 DBG Trying to open CHD file path="PS3ISO///Bayonetta (USA) (En,Ja,Fr,De,Es,It).chd"
2026-04-03T20:32:18.330570-05:00 homeserver ps3netsrv-go[152877]: Apr  3 20:32:18.330 ERR CHD file open for stat failed, report as try next err="chd: open: invalid data"

Then, I started to dig more and more and created more CHD files and discovered this:

Apparently, the CHD library (or something else, maybe even ps3netsrv-go) can't open CHD files in that its generated ISO file is above 10GB ... if the original ISO was below it, it works fine.

The actual size of the CHD does not mater.

I know the original ISOS work fine with ps3netsv-go because I tried FFXIII (44.7GB) and Borderlands Triple Pack (14.3GB) without issues.

I generated the CHD files using the "tochd" library like this:
tochd -qs -m dvd .

Then, I have tested the CHD files and getting the SHA1 hash from them using this command:
chdman info -i <filename>.chd

I have tested FFXIII and Borderlands for its hashes and they match from the ISO... I have yet to test all of my files, but I am positive it may not be an encoding issue ... at least not right now. But I'll try and extract the ISO from the CHD to see if there is an issue there.

[xakep666]

@kadai thank your for such kind of work. Looks like it's an issue inside libchdr because "invalid data" error is returned from it.
Next step is probably to write a simple console tools in C with libchdr usage and try to extract image using it. If it also ends up with error, you can file an issue in libchdr repo.

From my side I can implement more compressed image formats (cso/csov2, isz). They can be implemented in pure go, without external C libs.

[kadai]

I am going to report this to libchdr, and see what the developer/maintainer says... maybe all could be an issue for how the CHD are being created, as I have read that the CHD can handle sources of about 40GB or maybe more. Or maybe is a real bug in the library!

[treloret]

Found the issue in libchdr:

/* we're currently only using this for CD/DVDs, if we end up with more than 10GB data, it's probably invalid */
#define CHD_MAX_FILE_SIZE (10ULL * 1024 * 1024 * 1024)

[xakep666]

@treloret thank you! Looks like it's worth to add more compressed images format support. So I'll keep this issue open

[treloret]

Or change the 10ULL to 128ULL since BD is limited to 128GB.

[xakep666]

@treloret this is not easy to do because I'm loading already compiled library without any source code modifications. Such modification also may break something inside libchdr itself.

[treloret]

As the comment states, this was a sanity check in libchdr because no DVD would ever reach up to that number, think the error is only triggered once, when it tries to reach a sector count beyond 10GB. Any ISO file will have the same 2048 byte sector layout, no matter the original medium. But problem is best solved upstream in libchdr indeed.

[kadai]

@treloret this is not easy to do because I'm loading already compiled library without any source code modifications. Such modification also may break something inside libchdr itself.

Yes, is better to wait for the official library to be updated... but if that does not happens, can always ship a modified compiled version as most PS3 games are above 10GB

Also, I modified the libchdr_chd.c file to allow up to 128GB CHD files and tested it with my larger game (~44GB ISO, ~39GB CHD)... so far, it loaded fine (CHD was detected by webman-mod and mounted the CHD).

Played like for one hour with only one issue (maybe related to the fact the server was having a read overload as I was converting other titles to CHD).

Still, I'll test with other games. But so far, no hints that there may be issues by using this fix,

[treloret]

libchdr has been updated with a 1TB limit, with a formal release.

[xakep666]

@treloret thanks for notice. I'll update it a bit later.

[kadai]

@treloret thanks for notice. I'll update it a bit later.

thanks!

I have tested the new libchdr library, and while it opens the CHD properly... now I am getting this weird error and do not get any PS3 CHD detected... it tries to open "PS3ISO [auto]" and fails:

May  1 01:58:39.073 DBG Opener succeded request_path=PS3ISO// op=readdir opener=chd path="PS3ISO///Final Fantasy XIII (USA, Canada) (En,Fr,De,Es,It).chd"
May  1 01:58:39.074 DBG Received opcode remote=192.168.0.203:65363 opcode=CmdStatFile remote=192.168.0.203:65363
May  1 01:58:39.074 INF Stat file path="/PS3ISO [auto]" remote=192.168.0.203:65363
May  1 01:58:39.074 DBG Trying opener path_request="PS3ISO [auto]" fs_op=stat opener=viso remote=192.168.0.203:65363
May  1 01:58:39.074 DBG Trying opener path_request="PS3ISO [auto]" fs_op=stat opener=chd remote=192.168.0.203:65363
May  1 01:58:39.074 DBG Openers didn't succeed, trying native path_request="PS3ISO [auto]" fs_op=stat remote=192.168.0.203:65363
May  1 01:58:39.074 DBG Received opcode remote=192.168.0.203:65363 opcode=CmdOpenDir remote=192.168.0.203:65363
May  1 01:58:39.074 INF Open dir path="/PS3ISO [auto]//" remote=192.168.0.203:65363
May  1 01:58:39.075 DBG Trying opener path_request="PS3ISO [auto]//" fs_op=open opener=viso remote=192.168.0.203:65363
May  1 01:58:39.075 DBG Trying opener path_request="PS3ISO [auto]//" fs_op=open opener=chd remote=192.168.0.203:65363
May  1 01:58:39.075 DBG Openers didn't succeed, trying native path_request="PS3ISO [auto]//" fs_op=open remote=192.168.0.203:65363
May  1 01:58:39.075 WRN Open failed path="/PS3ISO [auto]//" err="openat PS3ISO [auto]//: no such file or directory" remote=192.168.0.203:65363
May  1 01:58:39.075 DBG Received opcode remote=192.168.0.203:65363 opcode=CmdReadDir remote=192.168.0.203:65363
May  1 01:58:39.075 INF Read dir path=PS3ISO// remote=192.168.0.203:65363

PSXISO with CHD files and PSPISO with CHD files are not affected

[xakep666]

This looks like a different problem. Quick search didn't reveal anything about "[auto]" suffix handling in original ps3netsrv. Maybe this related to "search in subdirectories" (inexact name) WebMAN option.

[kadai]

This looks like a different problem. Quick search didn't reveal anything about "[auto]" suffix handling in original ps3netsrv. Maybe this related to "search in subdirectories" (inexact name) WebMAN option.

yeah, is weird... only have seen ti pop-up when I add CHD files to the PS3ISO folder (or if it contains iso and chd mixed, only isos do not cause issues)