linux/include
Kefeng Wang 1027b96ec9 once: Fix panic when module unload
DO_ONCE
DEFINE_STATIC_KEY_TRUE(___once_key);
__do_once_done
  once_disable_jump(once_key);
    INIT_WORK(&w->work, once_deferred);
    struct once_work *w;
    w->key = key;
    schedule_work(&w->work);                     module unload
                                                   //*the key is
destroy*
process_one_work
  once_deferred
    BUG_ON(!static_key_enabled(work->key));
       static_key_count((struct static_key *)x)    //*access key, crash*

When module uses DO_ONCE mechanism, it could crash due to the above
concurrency problem, we could reproduce it with link[1].

Fix it by add/put module refcount in the once work process.

[1] https://lore.kernel.org/netdev/eaa6c371-465e-57eb-6be9-f4b16b9d7cbf@huawei.com/

Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Reported-by: Minmin chen <chenmingmin@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-08 13:00:20 +01:00
..
acpi ACPI: fix NULL pointer dereference 2021-07-24 15:25:54 -07:00
asm-generic This pull request contains the following changes for UML: 2021-07-09 10:19:13 -07:00
clocksource
crypto crypto: scatterwalk - Remove obsolete PageSlab check 2021-06-28 11:28:08 +08:00
drm drm: Return -ENOTTY for non-drm ioctls 2021-07-20 15:57:43 +02:00
dt-bindings dt-bindings: clock: r9a07g044-cpg: Update clock/reset definitions 2021-07-12 10:52:03 +02:00
keys
kunit linux-kselftest-kunit-fixes-5.14-rc1 2021-07-02 12:58:26 -07:00
kvm
linux once: Fix panic when module unload 2021-08-08 13:00:20 +01:00
math-emu math-emu: Fix fall-through warning 2021-07-13 13:57:44 -05:00
media
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2021-08-06 08:44:50 -07:00
pcmcia
ras
rdma
scsi SCSI misc on 20210702 2021-07-02 15:14:36 -07:00
soc Memory controller drivers for v5.14 - Tegra SoC, late fixes 2021-07-16 22:51:01 +02:00
sound ASoC: Fixes for v5.14 2021-07-21 19:48:09 +02:00
target
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-07-22 10:11:27 -07:00
uapi netfilter: nfnetlink_hook: missing chain family 2021-08-06 17:07:40 +02:00
vdso
video
xen xen: sync include/xen/interface/io/ring.h with Xen's newest version 2021-07-05 09:49:45 +02:00