[v2,0/3] afs: Fix dynamic root interaction with failing DNS lookups

Message

David Howells Dec. 11, 2023, 9:32 p.m. UTC

Hi Markus, Marc,

Here's a set of fixes to improve the interaction of arbitrary lookups in
the AFS dynamic root that hit DNS lookup failures[1]:

 (1) Always delete unused (particularly negative) dentries as soon as
     possible so that they don't prevent future lookups from retrying.

 (2) Fix the handling of new-style negative DNS lookups in ->lookup() to
     make them return ENOENT so that userspace doesn't get confused when
     stat succeeds but the following open on the looked up file then fails.

 (3) Fix key handling so that DNS lookup results are reclaimed as soon as
     they expire rather than sitting round either forever or for an
     additional 5 mins beyond a set expiry time returning EKEYEXPIRED.

The patches can be found here:

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

Thanks,
David

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216637 [1]
Link: https://lore.kernel.org/r/[e-mail] # v1

Changes
=======
ver #2)
 - Fix signed-unsigned comparison when checking return val.

David Howells (3):
  afs: Fix the dynamic root's d_delete to always delete unused dentries
  afs: Fix dynamic root lookup DNS check
  keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on
    expiry

 fs/afs/dynroot.c           | 31 +++++++++++++++++--------------
 include/linux/key-type.h   |  1 +
 net/dns_resolver/dns_key.c | 10 +++++++++-
 security/keys/gc.c         | 31 +++++++++++++++++++++----------
 security/keys/internal.h   |  8 +++++++-
 security/keys/key.c        | 15 +++++----------
 security/keys/proc.c       |  2 +-
 7 files changed, 61 insertions(+), 37 deletions(-)