[PATCH 0/2] AFS metadata xattr fixes

From: David Howells
Date: Thu Mar 11 2021 - 09:11:02 EST



Here's a pair of fixes for AFS.

(1) Fix an oops in AFS that can be triggered by accessing one of the
afs.yfs.* xattrs against a yfs server[1][2] - for instance by "cp -a"
or "rsync -X". These try and copy all of the xattrs.

They should pay attention to the list in /etc/xattr.conf, but cp
doesn't on Ubuntu and rsync doesn't seem to on Ubuntu or Fedora.
xattr.conf has been modified upstream[3], but a new version hasn't
been cut yet. I've logged a bug against rsync for the problem
there[4].

(2) Hide ACL-related AFS xattrs[6]. This removes them from the list
returned by listxattr(), but they're still available to get/set.

With further regard to the second patch, I tried just hiding the
appropriate ACL-related xattrs[5] first, but it didn't work well,
especially when a volume is replicated across servers of different types.

I wonder if it's better to just hide all the afs.* xattrs from listxattr().
It would probably be even better to not use xattrs for this, but I'm not
sure what I would use instead.

The patches can be found here:

https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=afs-fixes

David

Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003498.html [1]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003501.html [2]
Link: https://git.savannah.nongnu.org/cgit/attr.git/commit/?id=74da517cc655a82ded715dea7245ce88ebc91b98 [3]
Link: https://github.com/WayneD/rsync/issues/163 [4]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003516.html [5]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003524.html [6]
---
David Howells (2):
afs: Fix accessing YFS xattrs on a non-YFS server
afs: Fix afs_listxattr() to not list afs ACL special xattrs


fs/afs/xattr.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)