On Thu, Mar 16, 2017 at 8:35 PM, Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx> wrote: > Web: https://git.kernel.org/torvalds/c/630a04e79dd41ff746b545d4fc052e0abb836120 > Commit: 630a04e79dd41ff746b545d4fc052e0abb836120 > Parent: 2fcc319d2467a5f5b78f35f79fd6e22741a31b1e > Refname: refs/heads/master > Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > AuthorDate: Wed Mar 15 00:24:25 2017 -0700 > Committer: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > CommitDate: Wed Mar 15 00:24:25 2017 -0700 > > xfs: verify inline directory data forks > > When we're reading or writing the data fork of an inline directory, > check the contents to make sure we're not overflowing buffers or eating > garbage data. xfs/348 corrupts an inline symlink into an inline > directory, triggering a buffer overflow bug. > > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> > --- a/fs/xfs/libxfs/xfs_dir2_sf.c > +++ b/fs/xfs/libxfs/xfs_dir2_sf.c > +/* Verify the consistency of an inline directory. */ > +int > +xfs_dir2_sf_verify( > + struct xfs_mount *mp, > + struct xfs_dir2_sf_hdr *sfp, > + int size) > +{ > + /* Don't allow names with known bad length. */ > + XFS_WANT_CORRUPTED_RETURN(mp, sfep->namelen > 0); > + XFS_WANT_CORRUPTED_RETURN(mp, sfep->namelen < MAXNAMELEN); With gcc 4.1.2: fs/xfs/libxfs/xfs_dir2_sf.c: In function ‘xfs_dir2_sf_verify’: fs/xfs/libxfs/xfs_dir2_sf.c:680: warning: comparison is always true due to limited range of data type As sfep->namelen is __u8, and MAXNAMELEN = 256, none of the two checks above can be true. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
