From 8ceb0c18fc6778b662fff3517fec9aa7a05176a3 Mon Sep 17 00:00:00 2001 From: Christian Muehlhaeuser Date: Sun, 9 Jan 2022 11:29:05 +0100 Subject: [PATCH] fix: don't crash accessing invalid pathinfo When fs.Stat returns an error, pathinfo may be nil. In such situations the only safe response seems to be to return the error to the caller. Without this fix, accessing pathinfo.IsDir() below would lead to a crash dereferencing a nil pointer. This crash can be reproduced by trying to initialize a Git repo with an invalid path name. Also see: https://github.com/muesli/gitty/issues/36 --- repository.go | 3 +++ repository_test.go | 7 +++++++ 2 files changed, 10 insertions(+) diff --git a/repository.go b/repository.go index e8eb53f70..7292df627 100644 --- a/repository.go +++ b/repository.go @@ -280,6 +280,9 @@ func dotGitToOSFilesystems(path string, detect bool) (dot, wt billy.Filesystem, pathinfo, err := fs.Stat("/") if !os.IsNotExist(err) { + if pathinfo == nil { + return nil, nil, err + } if !pathinfo.IsDir() && detect { fs = osfs.New(filepath.Dir(path)) } diff --git a/repository_test.go b/repository_test.go index e284df8d6..5f542158e 100644 --- a/repository_test.go +++ b/repository_test.go @@ -2948,6 +2948,13 @@ func (s *RepositorySuite) TestBrokenMultipleShallowFetch(c *C) { c.Assert(err, IsNil) } +func TestDotGitToOSFilesystems(t *testing.T) { + _, _, err := dotGitToOSFilesystems("\000", false) + if err == nil { + t.Fatal("expected error, got nil") + } +} + func BenchmarkObjects(b *testing.B) { defer fixtures.Clean()