[PATCH 09/12] afs: Clear AFS_VNODE_CB_PROMISED if we detect callback expiry

[David Howells]

Fix afs_validate() to clear AFS_VNODE_CB_PROMISED on a vnode if we detect
any condition that causes the callback promise to be broken implicitly,
including server break (cb_s_break), volume break (cb_v_break) or callback
expiry.

Fixes: ae3b7361dc0e ("afs: Fix validation/callback interaction")
Reported-by: Marc Dionne <marc.dio...@auristor.com>
Signed-off-by: David Howells <dhowe...@redhat.com>
---

 fs/afs/inode.c |   14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index 3633703dbc0c..866d3575c5de 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -570,7 +570,7 @@ bool afs_check_validity(struct afs_vnode *vnode)
        struct afs_server *server;
        struct afs_volume *volume = vnode->volume;
        time64_t now = ktime_get_real_seconds();
-       bool valid;
+       bool valid, need_clear = false;
        unsigned int cb_break, cb_s_break, cb_v_break;
        int seq = 0;
 
@@ -588,10 +588,13 @@ bool afs_check_validity(struct afs_vnode *vnode)
                            vnode->cb_v_break != cb_v_break) {
                                vnode->cb_s_break = cb_s_break;
                                vnode->cb_v_break = cb_v_break;
+                               need_clear = true;
                                valid = false;
                        } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) 
{
+                               need_clear = true;
                                valid = false;
                        } else if (vnode->cb_expires_at - 10 <= now) {
+                               need_clear = true;
                                valid = false;
                        } else {
                                valid = true;
@@ -606,6 +609,15 @@ bool afs_check_validity(struct afs_vnode *vnode)
        } while (need_seqretry(&vnode->cb_lock, seq));
 
        done_seqretry(&vnode->cb_lock, seq);
+
+       if (need_clear) {
+               write_seqlock(&vnode->cb_lock);
+               if (cb_break == vnode->cb_break)
+                       __afs_break_callback(vnode);
+               write_sequnlock(&vnode->cb_lock);
+               valid = false;
+       }
+
        return valid;
 }