From 807a080d9574e42dae83bb8bd0863b110b98a858 Mon Sep 17 00:00:00 2001 From: Dean Deng Date: Thu, 31 Dec 2020 09:48:56 -0800 Subject: Add missing error checks for FileDescription.Init. Syzkaller discovered this bug in pipefs by doing something quite strange: creat(&(0x7f0000002a00)='./file1\x00', 0x0) mount(&(0x7f0000000440)=ANY=[], &(0x7f00000002c0)='./file1\x00', &(0x7f0000000300)='devtmpfs\x00', 0x20000d, 0x0) creat(&(0x7f0000000000)='./file1/file0\x00', 0x0) This can be reproduced with: touch mymount mkfifo /dev/mypipe mount -o ro -t devtmpfs devtmpfs mymount echo 123 > mymount/mypipe PiperOrigin-RevId: 349687714 --- pkg/sentry/fsimpl/ext/inode.go | 4 +++- pkg/sentry/fsimpl/pipefs/pipefs.go | 4 ++-- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'pkg/sentry/fsimpl') diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index 9009ba3c7..4a555bf72 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -200,7 +200,9 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOpt } var fd symlinkFD fd.LockFD.Init(&in.locks) - fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) + if err := fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { + return nil, err + } return &fd.vfsfd, nil default: panic(fmt.Sprintf("unknown inode type: %T", in.impl)) diff --git a/pkg/sentry/fsimpl/pipefs/pipefs.go b/pkg/sentry/fsimpl/pipefs/pipefs.go index 0ecb592cf..429733c10 100644 --- a/pkg/sentry/fsimpl/pipefs/pipefs.go +++ b/pkg/sentry/fsimpl/pipefs/pipefs.go @@ -164,11 +164,11 @@ func (i *inode) StatFS(ctx context.Context, fs *vfs.Filesystem) (linux.Statfs, e // and write ends of a newly-created pipe, as for pipe(2) and pipe2(2). // // Preconditions: mnt.Filesystem() must have been returned by NewFilesystem(). -func NewConnectedPipeFDs(ctx context.Context, mnt *vfs.Mount, flags uint32) (*vfs.FileDescription, *vfs.FileDescription) { +func NewConnectedPipeFDs(ctx context.Context, mnt *vfs.Mount, flags uint32) (*vfs.FileDescription, *vfs.FileDescription, error) { fs := mnt.Filesystem().Impl().(*filesystem) inode := newInode(ctx, fs) var d kernfs.Dentry d.Init(&fs.Filesystem, inode) defer d.DecRef(ctx) - return inode.pipe.ReaderWriterPair(mnt, d.VFSDentry(), flags) + return inode.pipe.ReaderWriterPair(ctx, mnt, d.VFSDentry(), flags) } -- cgit v1.2.3