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| author |   Eric Sandeen <sandeen@redhat.com> | 2020-08-26 14:11:58 -0700 |
|---|---|---|
| committer |   Darrick J. Wong <darrick.wong@oracle.com> | 2020-08-26 14:13:21 -0700 |
| commit | f4020438fab05364018c91f7e02ebdd192085933 (patch) | |
| tree | 41d1a045a0aad864a63228e69a41b936136fbe08 /fs/xfs/libxfs/xfs_attr_leaf.c | |
| parent | xfs: fix off-by-one in inode alloc block reservation calculation (diff) | |
| download | linux-dev-f4020438fab05364018c91f7e02ebdd192085933.tar.xz linux-dev-f4020438fab05364018c91f7e02ebdd192085933.zip | |
xfs: fix boundary test in xfs_attr_shortform_verify
The boundary test for the fixed-offset parts of xfs_attr_sf_entry in
xfs_attr_shortform_verify is off by one, because the variable array
at the end is defined as nameval[1] not nameval[].
Hence we need to subtract 1 from the calculation.
This can be shown by:
# touch file
# setfattr -n root.a file
and verifications will fail when it's written to disk.
This only matters for a last attribute which has a single-byte name
and no value, otherwise the combination of namelen & valuelen will
push endp further out and this test won't fail.
Fixes: 1e1bbd8e7ee06 ("xfs: create structure verifier function for shortform xattrs")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'fs/xfs/libxfs/xfs_attr_leaf.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_attr_leaf.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c index 8623c815164a..383b08f2ac61 100644 --- a/fs/xfs/libxfs/xfs_attr_leaf.c +++ b/fs/xfs/libxfs/xfs_attr_leaf.c @@ -1036,8 +1036,10 @@ xfs_attr_shortform_verify( * struct xfs_attr_sf_entry has a variable length. * Check the fixed-offset parts of the structure are * within the data buffer. + * xfs_attr_sf_entry is defined with a 1-byte variable + * array at the end, so we must subtract that off. */ - if (((char *)sfep + sizeof(*sfep)) >= endp) + if (((char *)sfep + sizeof(*sfep) - 1) >= endp) return __this_address; /* Don't allow names with known bad length. */ |