From 8655fb72482e179923987759f378543b2f489f08 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Fri, 19 Jun 2020 13:35:02 -0700 Subject: Fix vfs2 proc/self/fd dirent iteration. Make proc/self/fd iteration work properly. Also, the comment on kernfs.Inode.IterDirents did not accurately reflect how parameters should be used/were used in kernfs.Inode impls other than fdDir. Updates #2923. PiperOrigin-RevId: 317370325 --- pkg/sentry/fsimpl/kernfs/kernfs.go | 8 ++++---- pkg/sentry/fsimpl/proc/task_fds.go | 3 +-- 2 files changed, 5 insertions(+), 6 deletions(-) (limited to 'pkg') diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index bbee8ccda..07a9dc830 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -425,10 +425,10 @@ type inodeDynamicLookup interface { // IterDirents is used to iterate over dynamically created entries. It invokes // cb on each entry in the directory represented by the FileDescription. // 'offset' is the offset for the entire IterDirents call, which may include - // results from the caller. 'relOffset' is the offset inside the entries - // returned by this IterDirents invocation. In other words, - // 'offset+relOffset+1' is the value that should be set in vfs.Dirent.NextOff, - // while 'relOffset' is the place where iteration should start from. + // results from the caller (e.g. "." and ".."). 'relOffset' is the offset + // inside the entries returned by this IterDirents invocation. In other words, + // 'offset' should be used to calculate each vfs.Dirent.NextOff as well as + // the return value, while 'relOffset' is the place to start iteration. IterDirents(ctx context.Context, callback vfs.IterDirentsCallback, offset, relOffset int64) (newOffset int64, err error) } diff --git a/pkg/sentry/fsimpl/proc/task_fds.go b/pkg/sentry/fsimpl/proc/task_fds.go index 7debdb07a..fea29e5f0 100644 --- a/pkg/sentry/fsimpl/proc/task_fds.go +++ b/pkg/sentry/fsimpl/proc/task_fds.go @@ -64,7 +64,7 @@ type fdDir struct { } // IterDirents implements kernfs.inodeDynamicLookup. -func (i *fdDir) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, absOffset, relOffset int64) (int64, error) { +func (i *fdDir) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, offset, relOffset int64) (int64, error) { var fds []int32 i.task.WithMuLocked(func(t *kernel.Task) { if fdTable := t.FDTable(); fdTable != nil { @@ -72,7 +72,6 @@ func (i *fdDir) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, abs } }) - offset := absOffset + relOffset typ := uint8(linux.DT_REG) if i.produceSymlink { typ = linux.DT_LNK -- cgit v1.2.3