Re: [f2fs-dev] [PATCH 2/2] fsck.f2fs: fix to check validation of i_xattr_nid

[Jaegeuk Kim <jaegeuk@kernel.org>]

On 11/02, Chao Yu wrote:
> On 2020/11/2 10:39, Eric Biggers wrote:
> > On Mon, Nov 02, 2020 at 09:31:09AM +0800, Chao Yu wrote:
> > > On 2020/11/1 7:48, Eric Biggers wrote:
> > > > Hi Chao,
> > > > 
> > > > On Tue, Apr 07, 2020 at 06:01:07PM +0800, Chao Yu wrote:
> > > > > Otherwise, fsck.f2fs will access invalid memory address as below:
> > > > > 
> > > > > - fsck_verify
> > > > >    - dump_node
> > > > >     - dump_file
> > > > >      - dump_inode_blk
> > > > >       - dump_xattr
> > > > >        - read_all_xattrs
> > > > >          - get_node_info
> > > > >           access &(F2FS_FSCK(sbi)->entries[nid])
> > > > > 
> > > > > Signed-off-by: Chao Yu <yuchao0@huawei.com>
> > > > > ---
> > > > >    fsck/dump.c  |  2 ++
> > > > >    fsck/fsck.c  |  8 ++++++++
> > > > >    fsck/fsck.h  |  3 +++
> > > > >    fsck/mount.c |  8 +++++---
> > > > >    fsck/xattr.c | 20 ++++++++++++++++++--
> > > > >    5 files changed, 36 insertions(+), 5 deletions(-)
> > > > > 
> > > > 
> > > > This commit caused a regression where 'dump.f2fs -i <inode> <device>'
> > > > now segfaults if the inode has any extended attributes.
> > > > 
> > > > It's because read_all_xattrs() now calls fsck_sanity_check_nid(), which
> > > > eventually dereferences f2fs_fsck::main_area_bitmap, which is NULL.
> > > > 
> > > > I'm not sure what was intended here.
> > > 
> > > Eric, could you please have a try with below commit:
> > > 
> > > https://git.kernel.org/pub/scm/linux/kernel/git/chao/f2fs-tools.git/commit/?h=dev-test&id=aad80ed0099fb9530ae3af9789362353ff580252
> > > 
> > 
> > Works for me.  I was wondering whether the fix would be more than that, but
> > maybe not.
> 
> Thanks for both report and test.
> 
> I don't have any other concern on current solution, let's ask for Jaegeuk's
> opinion anyway.
> 
> Jaegeuk, could you please check previous buggy fix and current fix?

Thanks. I applied the new fix.

> 
> Thanks,
> 
> > 
> > - Eric
> > .
> > 


_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel