访问安装的目录时遇到分段违规

Question

segmentation violation code=0x1 error when accessing mounted network share

Ubuntu server running a golang applicaiton (PwnDelorian) crashes. Checked permissions of directory, everything seems fine there.

        fileList := []FileStruct{}
        err := filepath.Walk(dir, func(path string, f os.FileInfo, err error) error {
                fileList = append(fileList, FileStruct{f.Name(), path})
                return nil
        })
        if err != nil {
                return nil, err
        }
        return fileList, nil
}

> panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x30 pc=0x6482bf]

>goroutine 1 [running]:
main.getAllFilesInDirectory.func1(0xc42031d950, 0x49, 0x0, 0x0, 0x71ea20, 0xc4202ba990, 0x0, 0x0)
        /home/jim/go/src/PwnDelorean/filesystem.go:42 +0x2f
path/filepath.walk(0xc42030fa80, 0x3c, 0x721ec0, 0xc420357930, 0xc42009b730, 0x0, 0x0)
        /usr/lib/go-1.10/src/path/filepath/path.go:377 +0x20d
path/filepath.walk(0xc42033eab0, 0x24, 0x721ec0, 0xc420356c30, 0xc42009b730, 0x0, 0x0)
        /usr/lib/go-1.10/src/path/filepath/path.go:381 +0x2c2
path/filepath.walk(0xc420313260, 0x16, 0x721ec0, 0xc420356820, 0xc42009b730, 0x0, 0x0)
        /usr/lib/go-1.10/src/path/filepath/path.go:381 +0x2c2
path/filepath.walk(0x7ffd2448320a, 0x11, 0x721ec0, 0xc4200a1d40, 0xc42009b730, 0x0, 0x10)
        /usr/lib/go-1.10/src/path/filepath/path.go:381 +0x2c2
path/filepath.Walk(0x7ffd2448320a, 0x11, 0xc42009b730, 0x0, 0x4982c4)
        /usr/lib/go-1.10/src/path/filepath/path.go:403 +0x106
main.getAllFilesInDirectory(0x7ffd2448320a, 0x11, 0x11, 0x0, 0xc4200a1ba0, 0xc42006bdf0, 0x497b5d)
        /home/jim/go/src/PwnDelorean/filesystem.go:41 +0xc4
main.startFileSystemScan()
        /home/jim/go/src/PwnDelorean/filesystem.go:129 +0x4e
main.main()
        /home/jim/go/src/PwnDelorean/main.go:136 +0x91

Answer 1

panic: runtime error: invalid memory address or nil pointer dereference

Start with the documentation:

Package filepath

import "path/filepath"

type WalkFunc

In the case of an error, the info argument will be nil.

type WalkFunc func(path string, info os.FileInfo, err error) error