Upgrade random crashes

[msdobrescu]

Luet version:

luet version 0.0.0 (Build time: 2026-03-04)

CPU architecture, OS, and Version:

Linux MXT 7.0.10-mocaccino #7.0.10-Mocaccino SMP PREEMPT_DYNAMIC Mon May 25 10:05:45 UTC 20 x86_64 Intel(R) Core(TM) i7-3630QM CPU @ 2.40GHz GenuineIntel GNU/Linux

Describe the bug

During upgrade, some package (not necessarily the same) fails as follows:

 WARNING   failed downloading image quay.io/mocaccino/desktop:X-layers-26.06-3: unexpected EOF
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xb22d26]

goroutine 66 [running]:
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).generateSum(0x3ef50269dd30, 0x3ef50269dc10?, {{0x10182e0?, 0x3ef50c952d00?}, {0xf8c40b?, 0x188db60?}})
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:78 +0x66
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).generateSHA256(0x3ef50269dd30, 0x0)
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:73 +0x57
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).Generate(...)
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:60
github.com/mudler/luet/pkg/api/core/types/artifact.(*PackageArtifact).Verify(0x0)
        /luetbuild/luet/pkg/api/core/types/artifact/artifact.go:104 +0xb1
github.com/mudler/luet/pkg/installer.(*LuetInstaller).getPackage(0x3ef510c6f3e0?, {0x3ef5038f1680?, 0x3ef50016a990?, {0x1011d00?, 0x3ef502181d80?}}, {0x1027ca0?, 0x3ef4f9943130?})
        /luetbuild/luet/pkg/installer/installer.go:962 +0x65
github.com/mudler/luet/pkg/installer.(*LuetInstaller).downloadWorker(0x3ef4f9d94e00, 0x0?, 0x0?, 0x0, 0x3ef50dee4000, {0x1027ca0, 0x3ef4f9943130})
        /luetbuild/luet/pkg/installer/installer.go:996 +0x10e
created by github.com/mudler/luet/pkg/installer.(*LuetInstaller).download in goroutine 1
        /luetbuild/luet/pkg/installer/installer.go:674 +0x645
\033[32;5mDone!\033[0m

To Reproduce

Issue luet upgrade, but it happened on three systems today, randomly with regard to the package.
Each upgrade brings other package that breaks the process. so it seems it is not related to a specific package.
All machines are AMD64, one AMD, two Intel based.

Expected behavior

Logs

Not this time, sorry. It worked just when I've retried with --debug.

Additional context

[msdobrescu]

Another crash, this time on installing a package:

luet install -y apps/dotnet-sdk-10
 INFO  Luet 0.0.0 (Build time: 2026-03-04)
 INFO  Copyright (C) 2019-2022 Ettore Di Giacinto
       This program comes with ABSOLUTELY NO WARRANTY.
       This is free software, and you are welcome to redistribute it under certain conditions.
       For documentation, visit https://luet.io.
 INFO   :::> Install
 INFO   🤔  Checking for available upgrades                                                                                                                                                                                                                 
 INFO   Nothing to upgrade
 INFO   Packages that are going to be installed in the system:

Program Name                         | Version  | License | Repository                
apps/dotnet-runtime-nugets-10-10.0.3 | 10.0.3   | MIT     | mocaccino-community-stable
apps/dotnet-sdk-10-10.0.103          | 10.0.103 | MIT     | mocaccino-community-stable

Downloading packages [0/2] █                                                                                                                                                                                                                         0% | 0s
 INFO   Downloading image quay.io/mocaccino/mocaccino-community:dotnet-runtime-nugets-10-apps-10.0.3                                                                                                                                                        
 INFO   Downloading image quay.io/mocaccino/mocaccino-community:dotnet-sdk-10-apps-10.0.103                                                                                                                                                                 
 INFO   Image: quay.io/mocaccino/mocaccino-community:dotnet-sdk-10-apps-10.0.103. Pulled: sha256:0361c2ac7ebdcadc0f9afc6e4a1cf45325ed15819225b40f8648b57ccc03fcc7. Size: 608.2MiB                                                                           
Downloading packages [1/2] ███████████████████████████████████████████████████████████████████████████████████████████████████████████                                                                                                           50% | 3m25s
 WARNING   failed downloading image quay.io/mocaccino/mocaccino-community:dotnet-runtime-nugets-10-apps-10.0.3: failed to Lchown "/var/tmp/luet/image1516325033/opt/dotnet-nugets/microsoft.netcore.app.runtime.linux-musl-x64.8.0.24.nupkg" for UID 0, GID 0: lchown /var/tmp/luet/image1516325033/opt/dotnet-nugets/microsoft.netcore.app.runtime.linux-musl-x64.8.0.24.nupkg: no such file or directory
panic: runtime error: invalid memory address or nil pointer dereference                                                                                                                                                                                     
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xb22d26]

goroutine 26 [running]:
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).generateSum(0x2115ae939d30, 0x2115ae939c10?, {{0x10182e0?, 0x21159faaa180?}, {0xf8c40b?, 0x188db60?}})
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:78 +0x66
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).generateSHA256(0x2115ae939d30, 0x0)
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:73 +0x57
github.com/mudler/luet/pkg/api/core/types/artifact.(*Checksums).Generate(...)
        /luetbuild/luet/pkg/api/core/types/artifact/checksum.go:60
github.com/mudler/luet/pkg/api/core/types/artifact.(*PackageArtifact).Verify(0x0)
        /luetbuild/luet/pkg/api/core/types/artifact/artifact.go:104 +0xb1
github.com/mudler/luet/pkg/installer.(*LuetInstaller).getPackage(0x0?, {0x2115a1210140?, 0x211592a33b90?, {0x1011d00?, 0x211592455880?}}, {0x1027ca0?, 0x2115921dc730?})
        /luetbuild/luet/pkg/installer/installer.go:962 +0x65
github.com/mudler/luet/pkg/installer.(*LuetInstaller).downloadWorker(0x2115920fc000, 0x0?, 0x0?, 0x2115ae90e0b0, 0x2115aac3ab60, {0x1027ca0, 0x2115921dc730})
        /luetbuild/luet/pkg/installer/installer.go:996 +0x10e
created by github.com/mudler/luet/pkg/installer.(*LuetInstaller).download in goroutine 1
        /luetbuild/luet/pkg/installer/installer.go:674 +0x645