kernel/linux.git/drivers/net/wan/lapbether.c, branch v6.19.11

net: lapbether: ignore ops-locked netdevs

2025-08-08T20:22:28+00:00

Syzkaller managed to trigger lock dependency in xsk_notify via register_netdevice. As discussed in [0], using register_netdevice in the notifiers is problematic so skip adding lapbeth for ops-locked devices. xsk_notifier+0xa4/0x280 net/xdp/xsk.c:1645 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2230 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] unregister_netdevice_many_notify+0xf9d/0x2700 net/core/dev.c:12077 unregister_netdevice_many net/core/dev.c:12140 [inline] unregister_netdevice_queue+0x305/0x3f0 net/core/dev.c:11984 register_netdevice+0x18f1/0x2270 net/core/dev.c:11149 lapbeth_new_device drivers/net/wan/lapbether.c:420 [inline] lapbeth_device_event+0x5b1/0xbe0 drivers/net/wan/lapbether.c:462 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2230 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] __dev_notify_flags+0x12c/0x2e0 net/core/dev.c:9497 netif_change_flags+0x108/0x160 net/core/dev.c:9526 dev_change_flags+0xba/0x250 net/core/dev_api.c:68 devinet_ioctl+0x11d5/0x1f50 net/ipv4/devinet.c:1200 inet_ioctl+0x3a7/0x3f0 net/ipv4/af_inet.c:1001 0: https://lore.kernel.org/netdev/20250625140357.6203d0af@kernel.org/ Fixes: 4c975fd70002 ("net: hold instance lock during NETDEV_REGISTER/UP") Suggested-by: Jakub Kicinski Reported-by: syzbot+e67ea9c235b13b4f0020@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e67ea9c235b13b4f0020 Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250806213726.1383379-1-sdf@fomichev.me Signed-off-by: Jakub Kicinski

net: lapbether: use netdev_lockdep_set_classes() helper

2025-03-31T23:43:55+00:00

drivers/net/wan/lapbether.c uses stacked devices. Like similar drivers, it must use netdev_lockdep_set_classes() to avoid LOCKDEP splats. This is similar to commit 9bfc9d65a1dc ("hamradio: use netdev_lockdep_set_classes() helper") Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations") Reported-by: syzbot+377b71db585c9c705f8e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/67cd611c.050a0220.14db68.0073.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250327144439.2463509-1-edumazet@google.com Signed-off-by: Jakub Kicinski

net: lapbether: only support ethernet devices

2023-06-15T07:55:22+00:00

It probbaly makes no sense to support arbitrary network devices for lapbether. syzbot reported: skbuff: skb_under_panic: text:ffff80008934c100 len:44 put:40 head:ffff0000d18dd200 data:ffff0000d18dd1ea tail:0x16 end:0x140 dev:bond1 kernel BUG at net/core/skbuff.c:200 ! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 5643 Comm: dhcpcd Not tainted 6.4.0-rc5-syzkaller-g4641cff8e810 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : skb_panic net/core/skbuff.c:196 [inline] pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:210 lr : skb_panic net/core/skbuff.c:196 [inline] lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:210 sp : ffff8000973b7260 x29: ffff8000973b7270 x28: ffff8000973b7360 x27: dfff800000000000 x26: ffff0000d85d8150 x25: 0000000000000016 x24: ffff0000d18dd1ea x23: ffff0000d18dd200 x22: 000000000000002c x21: 0000000000000140 x20: 0000000000000028 x19: ffff80008934c100 x18: ffff8000973b68a0 x17: 0000000000000000 x16: ffff80008a43bfbc x15: 0000000000000202 x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000001 x11: 0000000000000201 x10: 0000000000000000 x9 : f22f7eb937cced00 x8 : f22f7eb937cced00 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff8000973b6b78 x4 : ffff80008df9ee80 x3 : ffff8000805974f4 x2 : 0000000000000001 x1 : 0000000100000201 x0 : 0000000000000086 Call trace: skb_panic net/core/skbuff.c:196 [inline] skb_under_panic+0x13c/0x140 net/core/skbuff.c:210 skb_push+0xf0/0x108 net/core/skbuff.c:2409 ip6gre_header+0xbc/0x738 net/ipv6/ip6_gre.c:1383 dev_hard_header include/linux/netdevice.h:3137 [inline] lapbeth_data_transmit+0x1c4/0x298 drivers/net/wan/lapbether.c:257 lapb_data_transmit+0x8c/0xb0 net/lapb/lapb_iface.c:447 lapb_transmit_buffer+0x178/0x204 net/lapb/lapb_out.c:149 lapb_send_control+0x220/0x320 net/lapb/lapb_subr.c:251 lapb_establish_data_link+0x94/0xec lapb_device_event+0x348/0x4e0 notifier_call_chain+0x1a4/0x510 kernel/notifier.c:93 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:461 __dev_notify_flags+0x2bc/0x544 dev_change_flags+0xd0/0x15c net/core/dev.c:8643 devinet_ioctl+0x858/0x17e4 net/ipv4/devinet.c:1150 inet_ioctl+0x2ac/0x4d8 net/ipv4/af_inet.c:979 sock_do_ioctl+0x134/0x2dc net/socket.c:1201 sock_ioctl+0x4ec/0x858 net/socket.c:1318 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x244 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:191 el0_svc+0x4c/0x160 arch/arm64/kernel/entry-common.c:647 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 Code: aa1803e6 aa1903e7 a90023f5 947730f5 (d4210000) Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot Signed-off-by: Eric Dumazet Cc: Martin Schiller Signed-off-by: David S. Miller

net: lapbether: fix issue of invalid opcode in lapbeth_open()

2022-11-08T11:47:36+00:00

If lapb_register() failed when lapb device goes to up for the first time, the NAPI is not disabled. As a result, the invalid opcode issue is reported when the lapb device goes to up for the second time. The stack info is as follows: [ 1958.311422][T11356] kernel BUG at net/core/dev.c:6442! [ 1958.312206][T11356] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 1958.315979][T11356] RIP: 0010:napi_enable+0x16a/0x1f0 [ 1958.332310][T11356] Call Trace: [ 1958.332817][T11356] [ 1958.336135][T11356] lapbeth_open+0x18/0x90 [ 1958.337446][T11356] __dev_open+0x258/0x490 [ 1958.341672][T11356] __dev_change_flags+0x4d4/0x6a0 [ 1958.345325][T11356] dev_change_flags+0x93/0x160 [ 1958.346027][T11356] devinet_ioctl+0x1276/0x1bf0 [ 1958.346738][T11356] inet_ioctl+0x1c8/0x2d0 [ 1958.349638][T11356] sock_ioctl+0x5d1/0x750 [ 1958.356059][T11356] __x64_sys_ioctl+0x3ec/0x1790 [ 1958.365594][T11356] do_syscall_64+0x35/0x80 [ 1958.366239][T11356] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 1958.377381][T11356] Fixes: 514e1150da9c ("net: x25: Queue received packets in the drivers instead of per-CPU queues") Signed-off-by: Zhengchao Shao Link: https://lore.kernel.org/r/20221107011445.207372-1-shaozhengchao@huawei.com Signed-off-by: Paolo Abeni

net: lapbether: fix issue of dev reference count leakage in lapbeth_device_event()

2022-11-07T09:31:26+00:00

When following tests are performed, it will cause dev reference counting leakage. a)ip link add bond2 type bond mode balance-rr b)ip link set bond2 up c)ifenslave -f bond2 rose1 d)ip link del bond2 When new bond device is created, the default type of the bond device is ether. And the bond device is up, lapbeth_device_event() receives the message and creates a new lapbeth device. In this case, the reference count value of dev is hold once. But after "ifenslave -f bond2 rose1" command is executed, the type of the bond device is changed to rose. When the bond device is unregistered, lapbeth_device_event() will not put the dev reference count. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Zhengchao Shao Signed-off-by: David S. Miller

net: wan: switch to netif_napi_add_weight()

2022-05-08T10:33:57+00:00

A handful of WAN drivers use custom napi weights, switch them to the new API. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net: use dev_addr_set()

2021-10-09T10:55:01+00:00

Use dev_addr_set() instead of writing directly to netdev->dev_addr in various misc and old drivers. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net: lapbether: fix the code style issue about line length

2021-06-09T21:02:58+00:00

According to the chackpatch.pl, line length of 123 exceeds 100 columns, so fix it. Signed-off-by: Peng Li Signed-off-by: David S. Miller

net: lapbether: fix the alignment issue

2021-06-09T21:02:58+00:00

Alignment should match open parenthesis. Signed-off-by: Peng Li Signed-off-by: David S. Miller

net: lapbether: replace comparison to NULL with "lapbeth_get_x25_dev"

2021-06-09T21:02:58+00:00

According to the chackpatch.pl, comparison to NULL could be written "lapbeth_get_x25_dev". Signed-off-by: Peng Li Signed-off-by: David S. Miller