Fix afs_break_some_callbacks() to check to see if afs_lookup_volume_rcu() returned NULL (e.g. the specified volume is unknown). Fixes: 8230fd8217b7 ("afs: Make callback processing more efficient.") Closes: https://sashiko.dev/#/patchset/20260609081738.770127-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org --- fs/afs/callback.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/afs/callback.c b/fs/afs/callback.c index dd7a407ea368..74853e0d0435 100644 --- a/fs/afs/callback.c +++ b/fs/afs/callback.c @@ -213,7 +213,11 @@ static void afs_break_some_callbacks(struct afs_server *server, rcu_read_lock(); volume = afs_lookup_volume_rcu(server->cell, vid); - if (cbb->fid.vnode == 0 && cbb->fid.unique == 0) { + if (!volume) { + /* Ignore breaks on unknown volumes. */ + rcu_read_unlock(); + *_count = 0; + } else if (cbb->fid.vnode == 0 && cbb->fid.unique == 0) { afs_break_volume_callback(server, volume); *_count -= 1; if (*_count)