diff options
| author | Duoming Zhou <duoming@zju.edu.cn> | 2024-03-29 09:50:23 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-04-02 17:59:44 -0700 |
| commit | fd819ad3ecf6f3c232a06b27423ce9ed8c20da89 (patch) | |
| tree | 989b5dc0af01bf0de9fffdcc928d537e91ccdd74 /net | |
| parent | ea2a1cfc3b2019bdea6324acd3c03606b60d71ad (diff) | |
ax25: fix use-after-free bugs caused by ax25_ds_del_timer
When the ax25 device is detaching, the ax25_dev_device_down()
calls ax25_ds_del_timer() to cleanup the slave_timer. When
the timer handler is running, the ax25_ds_del_timer() that
calls del_timer() in it will return directly. As a result,
the use-after-free bugs could happen, one of the scenarios
is shown below:
(Thread 1) | (Thread 2)
| ax25_ds_timeout()
ax25_dev_device_down() |
ax25_ds_del_timer() |
del_timer() |
ax25_dev_put() //FREE |
| ax25_dev-> //USE
In order to mitigate bugs, when the device is detaching, use
timer_shutdown_sync() to stop the timer.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240329015023.9223-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ax25/ax25_dev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ax25/ax25_dev.c b/net/ax25/ax25_dev.c index c5462486dbca..282ec581c072 100644 --- a/net/ax25/ax25_dev.c +++ b/net/ax25/ax25_dev.c @@ -105,7 +105,7 @@ void ax25_dev_device_down(struct net_device *dev) spin_lock_bh(&ax25_dev_lock); #ifdef CONFIG_AX25_DAMA_SLAVE - ax25_ds_del_timer(ax25_dev); + timer_shutdown_sync(&ax25_dev->dama.slave_timer); #endif /* |