4.19-stable patches

added patches:
	libceph-fix-race-between-delayed_work-and-ceph_monc_stop.patch

diff --git a/queue-4.19/libceph-fix-race-between-delayed_work-and-ceph_monc_stop.patch b/queue-4.19/libceph-fix-race-between-delayed_work-and-ceph_monc_stop.patch
new file mode 100644 (file)
index 0000000..6540396
--- /dev/null
+++ b/queue-4.19/libceph-fix-race-between-delayed_work-and-ceph_monc_stop.patch
@@ -0,0 +1,86 @@
+From 69c7b2fe4c9cc1d3b1186d1c5606627ecf0de883 Mon Sep 17 00:00:00 2001
+From: Ilya Dryomov <idryomov@gmail.com>
+Date: Mon, 8 Jul 2024 22:37:29 +0200
+Subject: libceph: fix race between delayed_work() and ceph_monc_stop()
+
+From: Ilya Dryomov <idryomov@gmail.com>
+
+commit 69c7b2fe4c9cc1d3b1186d1c5606627ecf0de883 upstream.
+
+The way the delayed work is handled in ceph_monc_stop() is prone to
+races with mon_fault() and possibly also finish_hunting().  Both of
+these can requeue the delayed work which wouldn't be canceled by any of
+the following code in case that happens after cancel_delayed_work_sync()
+runs -- __close_session() doesn't mess with the delayed work in order
+to avoid interfering with the hunting interval logic.  This part was
+missed in commit b5d91704f53e ("libceph: behave in mon_fault() if
+cur_mon < 0") and use-after-free can still ensue on monc and objects
+that hang off of it, with monc->auth and monc->monmap being
+particularly susceptible to quickly being reused.
+
+To fix this:
+
+- clear monc->cur_mon and monc->hunting as part of closing the session
+  in ceph_monc_stop()
+- bail from delayed_work() if monc->cur_mon is cleared, similar to how
+  it's done in mon_fault() and finish_hunting() (based on monc->hunting)
+- call cancel_delayed_work_sync() after the session is closed
+
+Cc: stable@vger.kernel.org
+Link: https://tracker.ceph.com/issues/66857
+Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
+Reviewed-by: Xiubo Li <xiubli@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/ceph/mon_client.c |   14 ++++++++++++--
+ 1 file changed, 12 insertions(+), 2 deletions(-)
+
+--- a/net/ceph/mon_client.c
++++ b/net/ceph/mon_client.c
+@@ -963,13 +963,19 @@ static void delayed_work(struct work_str
+       struct ceph_mon_client *monc =
+               container_of(work, struct ceph_mon_client, delayed_work.work);
+ 
+-      dout("monc delayed_work\n");
+       mutex_lock(&monc->mutex);
++      dout("%s mon%d\n", __func__, monc->cur_mon);
++      if (monc->cur_mon < 0) {
++              goto out;
++      }
++
+       if (monc->hunting) {
+               dout("%s continuing hunt\n", __func__);
+               reopen_session(monc);
+       } else {
+               int is_auth = ceph_auth_is_authenticated(monc->auth);
++
++              dout("%s is_authed %d\n", __func__, is_auth);
+               if (ceph_con_keepalive_expired(&monc->con,
+                                              CEPH_MONC_PING_TIMEOUT)) {
+                       dout("monc keepalive timeout\n");
+@@ -994,6 +1000,8 @@ static void delayed_work(struct work_str
+               }
+       }
+       __schedule_delayed(monc);
++
++out:
+       mutex_unlock(&monc->mutex);
+ }
+ 
+@@ -1106,13 +1114,15 @@ EXPORT_SYMBOL(ceph_monc_init);
+ void ceph_monc_stop(struct ceph_mon_client *monc)
+ {
+       dout("stop\n");
+-      cancel_delayed_work_sync(&monc->delayed_work);
+ 
+       mutex_lock(&monc->mutex);
+       __close_session(monc);
++      monc->hunting = false;
+       monc->cur_mon = -1;
+       mutex_unlock(&monc->mutex);
+ 
++      cancel_delayed_work_sync(&monc->delayed_work);
++
+       /*
+        * flush msgr queue before we destroy ourselves to ensure that:
+        *  - any work that references our embedded con is finished.

diff --git a/queue-4.19/series b/queue-4.19/series
index a3848554844a03106dd385954002fe8f105187f9..c0d409f3ef05ecf17dc84244094b9776863e9935 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -56,3 +56,4 @@ usb-add-usb_quirk_no_set_intf-quirk-for-start-bp-850k.patch
 usb-gadget-configfs-prevent-oob-read-write-in-usb_string_copy.patch
 usb-core-fix-duplicate-endpoint-bug-by-clearing-reserved-bits-in-the-descriptor.patch
 hpet-support-32-bit-userspace.patch
+libceph-fix-race-between-delayed_work-and-ceph_monc_stop.patch