From: David Howells Date: Mon, 22 Jun 2026 09:08:49 +0000 (+0100) Subject: afs: Fix missing NULL pointer check in afs_break_some_callbacks() X-Git-Tag: v7.2-rc2~14^2~10^2~6 X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=794a01110390c1b76f59ece773fb0fbfd89c6f5c;p=thirdparty%2Flinux.git afs: Fix missing NULL pointer check in afs_break_some_callbacks() 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 Link: https://patch.msgid.link/20260622090856.2746629-16-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner (Amutable) --- 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)