panic: runtime error: index out of range [0] with length 0

[nba1992]

What happened:
panic: runtime error: index out of range [0] with length 0 when dealing with files without extension.

What you expected to happen:
Support when file has no extension?

How to reproduce it (as minimally and precisely as possible):
On Windows, execute it , guaranteeing that inside a folder, there is a file without an extension.

Anything else we need to know?:
As mentioned in #1024, I tried to use the exclude as a workaround but didn't work.

Environment:
Application: grype
Version: 0.41.0
Syft Version: v0.50.0
BuildDate: 2022-07-06T15:20:18Z
GitCommit: 0e0a9d9e7a28592db489499db0294608e5fe69b8
GitDescription: v0.41.0
Platform: windows/amd64
GoVersion: go1.18.3
Compiler: gc
Supported DB Schema: 4

[spiffcs]

Updated the issue link -

Thanks for opening the bug @nba1992 - I'll link this with the other windows issue and try and get you guys a solution. We're working through a backlog of tickets right now so it might be some time before we get an update here. Pull requests or a more detailed stack trace with the exact command that caused it is always welcome if you have extra bandwidth.

Thanks again

[kzantow]

Sorry for the delay here @nba1992 -- could you try the latest version of Syft and provide the stack trace output if still seeing this issue?

[nba1992]

I had to run a vulnerability check again today.

Built: 2022-11-17 08:20:14 +0000 UTC
Schema: 5
Checksum: sha256:cc0cfd203f5f818f23f5374defc30f7b4efc48d42b14ff0b860af16724d44730
Status: valid
Application: grype
Version: 0.52.0
Syft Version: v0.60.3
BuildDate: 2022-11-03T17:15:32Z
GitCommit: c8ddd7e218f63eb3adac1ec98ba9d8db9f3f3fec
GitDescription: v0.52.0
Platform: windows/amd64
GoVersion: go1.18.7
Compiler: gc
Supported DB Schema: 5

After changing the $env:SYFT_LOG_LEVEL = "debug", i found what was happening, and it seems that for syft for windows does not support files without extension.
I deleted the problematic files/folder, and it finish with success.

Stacktrace:

[0000] INFO grype version: 0.52.0
[0000] DEBUG ├── buildDate: 2022-11-03T17:15:32Z
[0000] DEBUG ├── compiler: gc
[0000] DEBUG ├── gitCommit: c8ddd7e218f63eb3adac1ec98ba9d8db9f3f3fec
[0000] DEBUG ├── gitDescription: v0.52.0
[0000] DEBUG ├── goVersion: go1.18.7
[0000] DEBUG ├── platform: windows/amd64
[0000] DEBUG ├── syftVersion: v0.60.3
[0000] DEBUG └── version: 0.52.0
[0000] DEBUG gathering packages
[0000] DEBUG loading DB
[0000] DEBUG indexing filesystem path="D:\"
[0000] WARN unable to access path="D:\System Volume Information": open D:\System Volume Information: Access is denied.[0008] WARN unable to access path="/d/VB/crate/lib": unable to readlink for path="/d/VB/crate/lib": readlink /d/VB/crate/lib: The system cannot find the path specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/os-release" : CreateFile D:\etc: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/usr/lib/os-release" : CreateFile D:\usr: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/system-release-cpe" : CreateFile D:\etc: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/redhat-release" : CreateFile D:\etc: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/bin/busybox" : CreateFile D:\bin: The system cannot find the file specified.
[0010] INFO could not identify distro
[0010] INFO cataloging directory
[0010] DEBUG cataloging with "alpmdb-cataloger"
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/os-release" : CreateFile D:\etc: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/usr/lib/os-release" : CreateFile D:\usr: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/system-release-cpe" : CreateFile D:\etc: The system cannot find the file specified.
[0010] DEBUG directory resolver unable to evaluate symlink for path="/etc/redhat-release" : CreateFile D:\etc: The system cannot find the file specified.
[0011] DEBUG directory resolver unable to evaluate symlink for path="/bin/busybox" : CreateFile D:\bin: The system cannot find the file specified.
[0013] DEBUG directory resolver unable to evaluate symlink for path="D:\VB\chocolatey-tools\msys64\var\lib\pacman\local\gmp-6.2.1-1\mtree" : CreateFile D:\D:: The filename, directory name, or volume label syntax is incorrect.
panic: runtime error: index out of range [0] with length 0

goroutine 36 [running]:
github.com/anchore/syft/syft/pkg/cataloger/alpm.getFileReader({0xc0081270e0, 0x44}, {0x29cb570, 0xc00028ad20})
/Users/runner/go/pkg/mod/github.com/anchore/syft@v0.60.3/syft/pkg/cataloger/alpm/parse_alpm_db.go:110 +0x1a5
github.com/anchore/syft/syft/pkg/cataloger/alpm.parseAlpmDB({0x29cb570, 0xc00028ad20}, 0xc00d28ea28, {{{{0xc0080d2b90, 0x43}, {0x0, 0x0}}, {0x0, 0x0}, {0x18fdb, ...}}, ...})
/Users/runner/go/pkg/mod/github.com/anchore/syft@v0.60.3/syft/pkg/cataloger/alpm/parse_alpm_db.go:41 +0x13d
github.com/anchore/syft/syft/pkg/cataloger/generic.(*Cataloger).Catalog(0xc007c22810, {0x29cb570, 0xc00028ad20})
/Users/runner/go/pkg/mod/github.com/anchore/syft@v0.60.3/syft/pkg/cataloger/generic/cataloger.go:127 +0x70e
github.com/anchore/syft/syft/pkg/cataloger.Catalog({0x29cb570?, 0xc00028ad20}, 0x8?, {0xc00037ef20, 0x16, 0x0?})
/Users/runner/go/pkg/mod/github.com/anchore/syft@v0.60.3/syft/pkg/cataloger/catalog.go:54 +0x3d8
github.com/anchore/syft/syft.CatalogPackages(0xc0004fca80, {{0x1, 0x0, {0x2423d77, 0x8}}, {0x0, 0x0, 0x0}})
/Users/runner/go/pkg/mod/github.com/anchore/syft@v0.60.3/syft/lib.go:72 +0x5a5
github.com/anchore/grype/grype/pkg.syftProvider({0xc0000460b0?, 0x0?}, {0xc0006a71d0, {0x3e47a58, 0x0, 0x0}, {{0x1, 0x0, {0x2423d77, 0x8}}, ...}, ...})
/Users/runner/work/grype/grype/grype/pkg/syft_provider.go:24 +0x17e
github.com/anchore/grype/grype/pkg.Provide({0xc0000460b0, 0x8}, {0xc0006a71d0, {0x3e47a58, 0x0, 0x0}, {{0x1, 0x0, {0x2423d77, 0x8}}, ...}, ...})
/Users/runner/work/grype/grype/grype/pkg/provider.go:32 +0x20c
github.com/anchore/grype/cmd.startWorker.func1.2()
/Users/runner/work/grype/grype/cmd/root.go:342 +0x16f
created by github.com/anchore/grype/cmd.startWorker.func1
/Users/runner/work/grype/grype/cmd/root.go:339 +0x83d

[erik-bershel]

Hello @spiffcs, @kzantow
We got the same error for both latest and previous releases.

Error:
[xxxx] DEBUG directory resolver unable to evaluate symlink for path="C:\msys64\var\lib\pacman\local\libp11-kit-0.24.1-4\mtree" : CreateFile C:\C:: The filename, directory name, or volume label syntax is incorrect.
panic: runtime error: index out of range [0] with length 0

Repro steps (with choco, prev. version): run workflow with job:

  Windows:
    runs-on: windows-2019
    steps:
      - name: 'Install syft'
        run: choco install syft -y
        
      - name: 'Creating SBOM'
        run: syft dir:C:/ -vv -o spdx-json=sbom.json

Logs: logs_74.zip

Repro steps (installed from sources, latest) : run workflow with job:

  Windows:
    runs-on: windows-2019
    steps:
      - name: 'Install syft'
        run: curl -sSfL https://raw.githubusercontent.com/anchore/syft/main/install.sh | sh -s -- -b D:/syft

      - name: 'Creating SBOM'
        run: D:/syft/syft dir:C:/ -vv -o spdx-json=sbom.json

Logs: logs_77.zip

[spiffcs]

#1366 removes the panic condition. We should start seeing sane errors again for this failure. Based on the debug log posted by @erik-bershel it looks like the directory resolver needs a look so that the symlinks are being handled correctly.

[spiffcs]

Closing this since the underlying panic has been solved. Kept the replication and steps for debugging purposes on the new #1373 issue that addresses the directory resolution error case