On 04/11/2024 16:32, Tiwei Bie wrote:
The drvdata is not available in release. Let's just use container_of() to get the uml_net instance. Otherwise, removing a network device will result in a crash:
RIP: 0033:net_device_release+0x10/0x6f RSP: 00000000e20c7c40 EFLAGS: 00010206 RAX: 000000006002e4e7 RBX: 00000000600f1baf RCX: 00000000624074e0 RDX: 0000000062778000 RSI: 0000000060551c80 RDI: 00000000627af028 RBP: 00000000e20c7c50 R08: 00000000603ad594 R09: 00000000e20c7b70 R10: 000000000000135a R11: 00000000603ad422 R12: 0000000000000000 R13: 0000000062c7af00 R14: 0000000062406d60 R15: 00000000627700b6 Kernel panic - not syncing: Segfault with no mm CPU: 0 UID: 0 PID: 29 Comm: kworker/0:2 Not tainted 6.12.0-rc6-g59b723cd2adb #1 Workqueue: events mc_work_proc Stack: 627af028 62c7af00 e20c7c80 60276fcd 62778000 603f5820 627af028 00000000 e20c7cb0 603a2bcd 627af000 62770010 Call Trace: [<60276fcd>] device_release+0x70/0xba [<603a2bcd>] kobject_put+0xba/0xe7 [<60277265>] put_device+0x19/0x1c [<60281266>] platform_device_put+0x26/0x29 [<60281e5f>] platform_device_unregister+0x2c/0x2e [<6002ec9c>] net_remove+0x63/0x69 [<60031316>] ? mconsole_reply+0x0/0x50 [<600310c8>] mconsole_remove+0x160/0x1cc [<60087d40>] ? __remove_hrtimer+0x38/0x74 [<60087ff8>] ? hrtimer_try_to_cancel+0x8c/0x98 [<6006b3cf>] ? dl_server_stop+0x3f/0x48 [<6006b390>] ? dl_server_stop+0x0/0x48 [<600672e8>] ? dequeue_entities+0x327/0x390 [<60038fa6>] ? um_set_signals+0x0/0x43 [<6003070c>] mc_work_proc+0x77/0x91 [<60057664>] process_scheduled_works+0x1b3/0x2dd [<60055f32>] ? assign_work+0x0/0x58 [<60057f0a>] worker_thread+0x1e9/0x293 [<6005406f>] ? set_pf_worker+0x0/0x64 [<6005d65d>] ? arch_local_irq_save+0x0/0x2d [<6005d748>] ? kthread_exit+0x0/0x3a [<60057d21>] ? worker_thread+0x0/0x293 [<6005dbf1>] kthread+0x126/0x12b [<600219c5>] new_thread_handler+0x85/0xb6
Cc: stable@vger.kernel.org Signed-off-by: Tiwei Bie tiwei.btw@antgroup.com
arch/um/drivers/net_kern.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c index 77c4afb8ab90..75d04fb4994a 100644 --- a/arch/um/drivers/net_kern.c +++ b/arch/um/drivers/net_kern.c @@ -336,7 +336,7 @@ static struct platform_driver uml_net_driver = { static void net_device_release(struct device *dev) {
- struct uml_net *device = dev_get_drvdata(dev);
- struct uml_net *device = container_of(dev, struct uml_net, pdev.dev); struct net_device *netdev = device->dev; struct uml_net_private *lp = netdev_priv(netdev);
Acked-By: Anton Ivanov anton.ivanov@cambridgegreys.com