1 files changed, 49 insertions, 0 deletions
diff --git a/SOURCES/0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch b/SOURCES/0001-xfs-fix-boundary-test-in-xfs_attr_shortform_verify.patch
new file mode 100644
index 0000000..771f439
--- /dev/null
+++ b/SOURCES/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
+