| Message ID | 20190309034331.17944-1-yuehaibing@huawei.com |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | David Miller |
| Headers | show |
| Series | can: af_can: Fix possible NULL pointer dereference in can_exit | expand |
ping... On 2019/3/9 11:43, Yue Haibing wrote: > From: YueHaibing <yuehaibing@huawei.com> > > Syzkaller report this: > > kasan: GPF could be caused by NULL-ptr deref or user memory access > general protection fault: 0000 [#1] SMP KASAN PTI > CPU: 0 PID: 9400 Comm: syz-executor.0 Tainted: G C 5.0.0-rc8+ #3 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 > RIP: 0010:__list_del include/linux/list.h:105 [inline] > RIP: 0010:__list_del_entry include/linux/list.h:120 [inline] > RIP: 0010:list_del include/linux/list.h:125 [inline] > RIP: 0010:__unregister_pernet_operations net/core/net_namespace.c:1075 [inline] > RIP: 0010:unregister_pernet_operations+0x124/0x540 net/core/net_namespace.c:1137 > Code: 89 c1 48 c1 e9 03 80 3c 11 00 0f 85 38 03 00 00 48 8d 7d 08 48 ba 00 00 00 00 00 fc ff df 4d 8b 7c 24 08 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 02 03 00 00 48 8d 9c 24 b8 00 00 00 48 ba 00 00 > RSP: 0018:ffff8881b871fbb0 EFLAGS: 00010a06 > RAX: ffffffffc198c4c8 RBX: dffffc0000000000 RCX: 1bd5a00000000021 > RDX: dffffc0000000000 RSI: ffffc900014c4000 RDI: dead000000000108 > RBP: dead000000000100 R08: 0000000000000001 R09: 0000000000000000 > R10: ffff8881b871fb30 R11: 0000000000000000 R12: ffffffffc198c4c0 > R13: ffff8881b871fbe8 R14: 1ffff110370e3f79 R15: dead000000000200 > FS: 00007f029df32700(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007ffc85454218 CR3: 00000001e0ff4004 CR4: 00000000007606f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > unregister_pernet_subsys+0x1d/0x30 net/core/net_namespace.c:1184 > can_exit+0x3f/0x56 [can] > __do_sys_delete_module kernel/module.c:1018 [inline] > __se_sys_delete_module kernel/module.c:961 [inline] > __x64_sys_delete_module+0x3dc/0x5e0 kernel/module.c:961 > do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x462e99 > Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007f029df31c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0 > RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 > RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007f029df326bc > R13: 00000000004bcca9 R14: 00000000006f6b48 R15: 00000000ffffffff > > register_pernet_subsys may fails in can_init,then can_exit calls > unregister_pernet_subsys when unloading, it can trigger a NULL > pointer dereference while doing list_del.This patch fix error > cleanup path of can_init to avoid this. > > Reported-by: Hulk Robot <hulkci@huawei.com> > Signed-off-by: YueHaibing <yuehaibing@huawei.com> > --- > net/can/af_can.c | 24 +++++++++++++++++++++--- > 1 file changed, 21 insertions(+), 3 deletions(-) > > diff --git a/net/can/af_can.c b/net/can/af_can.c > index 1684ba5..5d75685 100644 > --- a/net/can/af_can.c > +++ b/net/can/af_can.c > @@ -958,6 +958,8 @@ static struct pernet_operations can_pernet_ops __read_mostly = { > > static __init int can_init(void) > { > + int rc; > + > /* check for correct padding to be able to use the structs similarly */ > BUILD_BUG_ON(offsetof(struct can_frame, can_dlc) != > offsetof(struct canfd_frame, len) || > @@ -971,15 +973,31 @@ static __init int can_init(void) > if (!rcv_cache) > return -ENOMEM; > > - register_pernet_subsys(&can_pernet_ops); > + rc = register_pernet_subsys(&can_pernet_ops); > + if (rc) > + goto free_cache; > > /* protocol register */ > - sock_register(&can_family_ops); > - register_netdevice_notifier(&can_netdev_notifier); > + rc = sock_register(&can_family_ops); > + if (rc) > + goto unregister_pernet; > + > + rc = register_netdevice_notifier(&can_netdev_notifier); > + if (rc) > + goto sock_unregister; > + > dev_add_pack(&can_packet); > dev_add_pack(&canfd_packet); > > return 0; > + > +sock_unregister: > + sock_unregister(PF_CAN); > +unregister_pernet: > + unregister_pernet_subsys(&can_pernet_ops); > +free_cache: > + kmem_cache_destroy(rcv_cache); > + return rc; > } > > static __exit void can_exit(void) >
diff --git a/net/can/af_can.c b/net/can/af_can.c index 1684ba5..5d75685 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -958,6 +958,8 @@ static struct pernet_operations can_pernet_ops __read_mostly = { static __init int can_init(void) { + int rc; + /* check for correct padding to be able to use the structs similarly */ BUILD_BUG_ON(offsetof(struct can_frame, can_dlc) != offsetof(struct canfd_frame, len) || @@ -971,15 +973,31 @@ static __init int can_init(void) if (!rcv_cache) return -ENOMEM; - register_pernet_subsys(&can_pernet_ops); + rc = register_pernet_subsys(&can_pernet_ops); + if (rc) + goto free_cache; /* protocol register */ - sock_register(&can_family_ops); - register_netdevice_notifier(&can_netdev_notifier); + rc = sock_register(&can_family_ops); + if (rc) + goto unregister_pernet; + + rc = register_netdevice_notifier(&can_netdev_notifier); + if (rc) + goto sock_unregister; + dev_add_pack(&can_packet); dev_add_pack(&canfd_packet); return 0; + +sock_unregister: + sock_unregister(PF_CAN); +unregister_pernet: + unregister_pernet_subsys(&can_pernet_ops); +free_cache: + kmem_cache_destroy(rcv_cache); + return rc; } static __exit void can_exit(void)