diff options
Diffstat (limited to '0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch')
| -rw-r--r-- | 0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch b/0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch new file mode 100644 index 000000000..771f4396e --- /dev/null +++ b/0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch @@ -0,0 +1,49 @@ +From f4020438fab05364018c91f7e02ebdd192085933 Mon Sep 17 00:00:00 2001 +From: Eric Sandeen <sandeen@redhat.com> +Date: Wed, 26 Aug 2020 14:11:58 -0700 +Subject: [PATCH] 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> +--- + fs/xfs/libxfs/xfs_attr_leaf.c | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +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. */ +-- +2.26.2 + |