Description

socketFileExists only returns early when os.Stat fails with an "not exists" error. For any other stat error (for example ENOTDIR when a path component is a regular file, or a permission error), info is nil but the code still calls info.IsDir(), causing a nil pointer dereference panic.

This is reachable from BuildConnectionFromOpts for the MySQL driver when a user passes a --socket path whose parent is not a directory. The fix treats any stat error as "socket does not exist".

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Added TestSocketFileExistsStatError, which points the helper at a .sock path that traverses through a regular file (yielding a non-IsNotExist stat error). The test panics on the old code and passes with the fix. Verified with go test -short -race ./pkg/connection/, go vet, and gofmt.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have added tests that prove my fix is effective
• New and existing unit tests pass locally with my changes