[Windows] Not able to scan volume mounted to folder

[dd-cws]

What happened:
syft fails to read directory which has a volume mounted on it.
Say F: is mounted on C:\Temp\Mounts\F and syft is executed as:
syft.exe packages dir:C:\Temp\Mounts\
it fails with following error:

[0000]  WARN unable to access path="/C/Temp/Mounts/F": unable to readlink for path="/C/Temp/Mounts/F": readlink /C/Temp/Mounts/F: The system cannot find the path specified.
No packages discovered

What you expected to happen:
syft should scan the entire folder C:\Temp\Mounts including mounted volume

Steps to reproduce the issue:
Create a folder C:\Temp\Mounts\F
Follow below steps to mount F: drive to C:\Temp\Mounts\F

1. Create empty folder C:\Temp\Mounts\F
2. Press Win + R keys to open Run and type diskmgmt.msc into Run and hit enter
3. In the disk management UI find F: drive, right click and select Change Drive Letter and Paths
4. Click on Add
5. In the textbox type C:\Temp\Mounts\F and click ok

Run syft.exe packages C:\Temp\Mounts

Anything else we need to know?:
The problem seems to be with the call to os.Readlink(p) in syft/source/directory_indexer.go in function addSymlinkToIndex
This should be replaced by filepath.EvalSymlinks(p)

Below is a quick patch that works for me:

diff --git a/syft/source/directory_indexer.go b/syft/source/directory_indexer.go
index e840a9dd..0cb2fe45 100644
--- a/syft/source/directory_indexer.go
+++ b/syft/source/directory_indexer.go
@@ -234,7 +234,16 @@ func (r directoryIndexer) addFileToIndex(p string, info os.FileInfo) error {
 }
 
 func (r directoryIndexer) addSymlinkToIndex(p string, info os.FileInfo) (string, error) {
-	linkTarget, err := os.Readlink(p)
+	if runtime.GOOS == WindowsOS {
+		p = posixToWindows(p)
+	}
+
+	linkTarget, err := filepath.EvalSymlinks(p)
+
+	if runtime.GOOS == WindowsOS {
+		p = windowsToPosix(p)
+	}
+
 	if err != nil {
 		return "", fmt.Errorf("unable to readlink for path=%q: %w", p, err)
 	}

Environment:

• Output of syft version: 0.80.0
• OS (e.g: cat /etc/os-release or similar): Windows 11

[tgerla]

Hi @dd-cws, thank you for the issue and sorry for the delay replying. Would you be able to submit your patch as a pull request to the Syft repository? We can do some basic testing and hopefully merge it. Let us know if you need any help with that. We appreciate it.

[dd-cws]

Sure, I would be happy to do so. Let me go through your PR submission process and create one.

[kzantow]

Hi @dd-cws, I'm a bit stuck following the instructions on step 3 (In the disk management UI find F: drive, right click and select Change Drive Letter and Paths) -- I do not see an F: drive, is there some other step that was missed to get this to show up?

[dd-cws]

Hey @kzantow, may be I wasn't clear in the instructions above. But F: drive is just an example I took. You can try to mount any drive available on your machine to a folder (even C:).
Hope this helps.