From: Chen Zhongjin <chenzhongjin@huawei.com> stable inclusion from stable-v4.19.270 commit 09be0e7ac5f9374b6f8de72c89ed67129af71f65 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ID0VG9 CVE: CVE-2022-50538 [ 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> Signed-off-by: Xiaomeng Zhang <zhangxiaomeng13@huawei.com> --- drivers/vme/bridges/vme_fake.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/vme/bridges/vme_fake.c b/drivers/vme/bridges/vme_fake.c index 7d83691047f4..142e784b60f4 100644 --- a/drivers/vme/bridges/vme_fake.c +++ b/drivers/vme/bridges/vme_fake.c @@ -1071,6 +1071,8 @@ 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. -- 2.34.1