From: Chen Zhongjin chenzhongjin@huawei.com
[ Upstream commit 7bef797d707f1744f71156b21d41e3b8c946631f ]
In fake_init(), __root_device_register() is possible to fail but it's ignored, which can cause unregistering vme_root fail when exit.
general protection fault, probably for non-canonical address 0xdffffc000000008c KASAN: null-ptr-deref in range [0x0000000000000460-0x0000000000000467] RIP: 0010:root_device_unregister+0x26/0x60 Call Trace: <TASK> __x64_sys_delete_module+0x34f/0x540 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Return error when __root_device_register() fails.
Fixes: 658bcdae9c67 ("vme: Adding Fake VME driver") Signed-off-by: Chen Zhongjin chenzhongjin@huawei.com Link: https://lore.kernel.org/r/20221205084805.147436-1-chenzhongjin@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/vme_user/vme_fake.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/staging/vme_user/vme_fake.c b/drivers/staging/vme_user/vme_fake.c index dd646b0c531d..1ee432c223e2 100644 --- a/drivers/staging/vme_user/vme_fake.c +++ b/drivers/staging/vme_user/vme_fake.c @@ -1073,6 +1073,8 @@ static int __init fake_init(void)
/* We need a fake parent device */ vme_root = __root_device_register("vme", THIS_MODULE); + if (IS_ERR(vme_root)) + return PTR_ERR(vme_root);
/* If we want to support more than one bridge at some point, we need to * dynamically allocate this so we get one per device.