On Fri, Sep 28, 2018 at 09:21:44AM -0700, Zubin Mithra wrote:
From: Theodore Ts'o tytso@mit.edu
commit 8cdb5240ec5928b20490a2bb34cb87e9a5f40226 upstream.
When expanding the extra isize space, we must never move the system.data xattr out of the inode body. For performance reasons, it doesn't make any sense, and the inline data implementation assumes that system.data xattr is never in the external xattr block.
This addresses CVE-2018-10880
https://bugzilla.kernel.org/show_bug.cgi?id=200005
Backport Note:
- dfa2064b22("ext4: factor out loop for freeing inode xattr space")
factored out the loop from inside ext4_expand_extra_isize_ea to a separate function named ext4_xattr_make_inode_space. As the above commit is not present in 4.4.y, make the change inside ext4_expand_extra_isize_ea.
What about a 4.9.y version of this? I can't just take a 4.4 version because someone would suffer a regression if they moved from 4.4.y to 4.9.y :(
thanks,
greg k-h