diff options
author | Darrick J. Wong <darrick.wong@oracle.com> | 2017-01-09 16:38:56 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-12 11:39:43 +0100 |
commit | f8b20705a383357ddca04ea648a7ac8fccd438ef (patch) | |
tree | 7a6df3b6f9ed6daeb677e238120d4bb6f714db70 /fs/xfs | |
parent | 12815dd15c480c0d595401e4eec54542025607f6 (diff) |
xfs: don't allow di_size with high bit set
commit ef388e2054feedaeb05399ed654bdb06f385d294 upstream.
The on-disk field di_size is used to set i_size, which is a signed
integer of loff_t. If the high bit of di_size is set, we'll end up with
a negative i_size, which will cause all sorts of problems. Since the
VFS won't let us create a file with such length, we should catch them
here in the verifier too.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/xfs')
-rw-r--r-- | fs/xfs/libxfs/xfs_inode_buf.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index 134424fac434..c906e50515f0 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -392,6 +392,14 @@ xfs_dinode_verify( if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC)) return false; + /* don't allow invalid i_size */ + if (be64_to_cpu(dip->di_size) & (1ULL << 63)) + return false; + + /* No zero-length symlinks. */ + if (S_ISLNK(be16_to_cpu(dip->di_mode)) && dip->di_size == 0) + return false; + /* only version 3 or greater inodes are extensively verified here */ if (dip->di_version < 3) return true; |