linux_dsm_epyc7002/include
Kefeng Wang fe0c9e93f5 once: Fix panic when module unload
[ Upstream commit 1027b96ec9d34f9abab69bc1a4dc5b1ad8ab1349 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05 18:56:55 +02:00
..
acpi
asm-generic vmlinux.lds.h: Handle clang's module.{c,d}tor sections 2024-07-05 18:55:16 +02:00
clocksource
crypto
drm
dt-bindings
keys
kunit
kvm
linux once: Fix panic when module unload 2024-07-05 18:56:55 +02:00
math-emu
media
memory
misc
net Revert "flow_offload: action should not be NULL when it is referenced" 2024-07-05 18:55:48 +02:00
pcmcia
ras
rdma
scsi
soc
sound
target
trace
uapi net: bridge: fix flags interpretation for extern learn fdb entries 2024-07-05 18:54:25 +02:00
vdso
video
xen