kernel/git/stable/linux.git/drivers/net/hamradio/bpqether.c, branch master

net: remove ax25 and amateur radio (hamradio) subsystem

2026-04-23T17:24:02+00:00

Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation and all associated hamradio device drivers from the kernel tree. This set of protocols has long been a huge bug/syzbot magnet, and since nobody stepped up to help us deal with the influx of the AI-generated bug reports we need to move it out of tree to protect our sanity. The code is moved to an out-of-tree repo: https://github.com/linux-netdev/mod-orphan if it's cleaned up and reworked there we can accept it back. Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP, AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN) so that the conditional integration code in arp.c and tun.c continues to compile and work when the out-of-tree modules are loaded. Signed-off-by: Jakub Kicinski Acked-by: Greg Kroah-Hartman Acked-by: Stephen Hemminger Acked-by: Carlos Bilbao Reviewed-by: Simon Horman Reviewed-by: Kuniyuki Iwashima Acked-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20260421021824.1293976-1-kuba@kernel.org Signed-off-by: Paolo Abeni

net: hamradio: bpqether: validate frame length in bpq_rcv()

2026-04-12T20:19:03+00:00

The BPQ length field is decoded as: len = skb->data[0] + skb->data[1] * 256 - 5; If the sender sets bytes [0..1] to values whose combined value is less than 5, len becomes negative. Passing a negative int to skb_trim() silently converts to a huge unsigned value, causing the function to be a no-op. The frame is then passed up to AX.25 with its original (untrimmed) payload, delivering garbage beyond the declared frame boundary. Additionally, a negative len corrupts the 64-bit rx_bytes counter through implicit sign-extension. Add a bounds check before pulling the length bytes: reject frames where len is negative or exceeds the remaining skb data. Acked-by: Joerg Reuter Signed-off-by: Mashiro Chen Link: https://patch.msgid.link/20260409024927.24397-2-mashiro.chen@mailbox.org Signed-off-by: Jakub Kicinski

hamradio: 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 hamradio for ops-locked devices. xsk_notifier+0x89/0x230 net/xdp/xsk.c:1664 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12156 unregister_netdevice_many net/core/dev.c:12219 [inline] unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12063 register_netdevice+0x1689/0x1ae0 net/core/dev.c:11241 bpq_new_device drivers/net/hamradio/bpqether.c:481 [inline] bpq_device_event+0x491/0x600 drivers/net/hamradio/bpqether.c:523 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9608 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 devinet_ioctl+0xbb4/0x1b50 net/ipv4/devinet.c:1200 inet_ioctl+0x3c0/0x4c0 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+e6300f66a999a6612477@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e6300f66a999a6612477 Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250806213726.1383379-2-sdf@fomichev.me Signed-off-by: Jakub Kicinski

net: move misc netdev_lock flavors to a separate header

2025-03-08T17:06:50+00:00

Move the more esoteric helpers for netdev instance lock to a dedicated header. This avoids growing netdevice.h to infinity and makes rebuilding the kernel much faster (after touching the header with the helpers). The main netdev_lock() / netdev_unlock() functions are used in static inlines in netdevice.h and will probably be used most commonly, so keep them in netdevice.h. Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250307183006.2312761-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

hamradio: use netdev_lockdep_set_classes() helper

2025-03-08T16:56:18+00:00

It is time to use netdev_lockdep_set_classes() in bpqether.c List of related commits: 0bef512012b1 ("net: add netdev_lockdep_set_classes() to virtual drivers") c74e1039912e ("net: bridge: use netdev_lockdep_set_classes()") 9a3c93af5491 ("vlan: use netdev_lockdep_set_classes()") 0d7dd798fd89 ("net: ipvlan: call netdev_lockdep_set_classes()") 24ffd752007f ("net: macvlan: call netdev_lockdep_set_classes()") 78e7a2ae8727 ("net: vrf: call netdev_lockdep_set_classes()") d3fff6c443fe ("net: add netdev_lockdep_set_classes() helper") syzbot reported: WARNING: possible recursive locking detected 6.14.0-rc5-syzkaller-01064-g2525e16a2bae #0 Not tainted dhcpcd/5501 is trying to acquire lock: ffff8880797e2d28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] ffff8880797e2d28 (&dev->lock){+.+.}-{4:4}, at: register_netdevice+0x12d8/0x1b70 net/core/dev.c:11008 but task is already holding lock: ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/linux/netdevice.h:2804 [inline] ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:65 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev->lock); lock(&dev->lock); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by dhcpcd/5501: #0: ffffffff8fed6848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fed6848 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x34c/0x1d80 net/ipv4/devinet.c:1121 #1: ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] #1: ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/linux/netdevice.h:2804 [inline] #1: ffff88802e530d28 (&dev->lock){+.+.}-{4:4}, at: dev_change_flags+0x120/0x270 net/core/dev_api.c:65 stack backtrace: CPU: 1 UID: 0 PID: 5501 Comm: dhcpcd Not tainted 6.14.0-rc5-syzkaller-01064-g2525e16a2bae #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3039 check_deadlock kernel/locking/lockdep.c:3091 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3893 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730 netdev_lock include/linux/netdevice.h:2765 [inline] register_netdevice+0x12d8/0x1b70 net/core/dev.c:11008 bpq_new_device drivers/net/hamradio/bpqether.c:499 [inline] bpq_device_event+0x4b1/0x8d0 drivers/net/hamradio/bpqether.c:542 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 __dev_notify_flags+0x207/0x400 netif_change_flags+0xf0/0x1a0 net/core/dev.c:9442 dev_change_flags+0x146/0x270 net/core/dev_api.c:66 devinet_ioctl+0xea2/0x1d80 net/ipv4/devinet.c:1200 inet_ioctl+0x3d7/0x4f0 net/ipv4/af_inet.c:1001 sock_do_ioctl+0x158/0x460 net/socket.c:1190 sock_ioctl+0x626/0x8e0 net/socket.c:1309 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations") Reported-by: syzbot Signed-off-by: Eric Dumazet Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250307160358.3153859-1-edumazet@google.com Signed-off-by: Jakub Kicinski

netdev_features: convert NETIF_F_LLTX to dev->lltx

2024-09-03T09:36:43+00:00

NETIF_F_LLTX can't be changed via Ethtool and is not a feature, rather an attribute, very similar to IFF_NO_QUEUE (and hot). Free one netdev_features_t bit and make it a "hot" private flag. Signed-off-by: Alexander Lobakin Signed-off-by: Paolo Abeni

hamradio: fix issue of dev reference count leakage in bpq_device_event()

2022-11-07T09:32:28+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, bpq_device_event() receives the message and creates a new bpq 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, bpq_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

hamradio: use dev_addr_set() for setting device address

2021-10-13T16:41:37+00:00

Use dev_addr_set() instead of writing to netdev->dev_addr directly in hamradio drivers. Signed-off-by: Jakub Kicinski

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

hamradio: use ndo_siocdevprivate

2021-07-27T19:11:44+00:00

hamradio uses a set of private ioctls that do seem to work correctly in compat mode, as they only rely on the ifr_data pointer. Move them over to the ndo_siocdevprivate callback as a cleanup. Cc: Thomas Sailer Cc: Joerg Reuter Cc: Jean-Paul Roubelat Cc: linux-hams@vger.kernel.org Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller