| Message ID | 20240620133119.1135480-1-edumazet@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 62e58ddb146502faff1dd23164a20688624eaaed |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] net: add softirq safety to netdev_rename_lock | expand |
Date: Thu, 20 Jun 2024 13:31:19 +0000 From: Eric Dumazet <edumazet@google.com> > syzbot reported a lockdep violation involving bridge driver [1] > > Make sure netdev_rename_lock is softirq safe to fix this issue. > > [1] > WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected > 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Not tainted > ----------------------------------------------------- > syz-executor.2/9449 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: > ffffffff8f5de668 (netdev_rename_lock.seqcount){+.+.}-{0:0}, at: rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839 > > and this task is already holding: > ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] > ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: br_port_slave_changelink+0x3d/0x150 net/bridge/br_netlink.c:1212 > which would create a new lock dependency: > (&br->lock){+.-.}-{2:2} -> (netdev_rename_lock.seqcount){+.+.}-{0:0} > > but this new dependency connects a SOFTIRQ-irq-safe lock: > (&br->lock){+.-.}-{2:2} [...] > Fixes: 0840556e5a3a ("net: Protect dev->name by seqlock.") > Reported-by: syzbot <syzkaller@googlegroups.com> > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Thanks!
Hello: This patch was applied to netdev/net.git (main) by David S. Miller <davem@davemloft.net>: On Thu, 20 Jun 2024 13:31:19 +0000 you wrote: > syzbot reported a lockdep violation involving bridge driver [1] > > Make sure netdev_rename_lock is softirq safe to fix this issue. > > [1] > WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected > 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Not tainted > > [...] Here is the summary with links: - [net] net: add softirq safety to netdev_rename_lock https://git.kernel.org/netdev/net/c/62e58ddb1465 You are awesome, thank you!
diff --git a/net/core/dev.c b/net/core/dev.c index 4d4de9008f6f3bd4e96b15fda5a2350d9d5efe10..2b4819b610b8a13e2bf355ef8c8b3a59f5e7497c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1226,9 +1226,9 @@ int dev_change_name(struct net_device *dev, const char *newname) memcpy(oldname, dev->name, IFNAMSIZ); - write_seqlock(&netdev_rename_lock); + write_seqlock_bh(&netdev_rename_lock); err = dev_get_valid_name(net, dev, newname); - write_sequnlock(&netdev_rename_lock); + write_sequnlock_bh(&netdev_rename_lock); if (err < 0) { up_write(&devnet_rename_sem); @@ -1269,9 +1269,9 @@ int dev_change_name(struct net_device *dev, const char *newname) if (err >= 0) { err = ret; down_write(&devnet_rename_sem); - write_seqlock(&netdev_rename_lock); + write_seqlock_bh(&netdev_rename_lock); memcpy(dev->name, oldname, IFNAMSIZ); - write_sequnlock(&netdev_rename_lock); + write_sequnlock_bh(&netdev_rename_lock); memcpy(oldname, newname, IFNAMSIZ); WRITE_ONCE(dev->name_assign_type, old_assign_type); old_assign_type = NET_NAME_RENAMED; @@ -11419,9 +11419,9 @@ int __dev_change_net_namespace(struct net_device *dev, struct net *net, if (new_name[0]) { /* Rename the netdev to prepared name */ - write_seqlock(&netdev_rename_lock); + write_seqlock_bh(&netdev_rename_lock); strscpy(dev->name, new_name, IFNAMSIZ); - write_sequnlock(&netdev_rename_lock); + write_sequnlock_bh(&netdev_rename_lock); } /* Fixup kobjects */
syzbot reported a lockdep violation involving bridge driver [1] Make sure netdev_rename_lock is softirq safe to fix this issue. [1] WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Not tainted ----------------------------------------------------- syz-executor.2/9449 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: ffffffff8f5de668 (netdev_rename_lock.seqcount){+.+.}-{0:0}, at: rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839 and this task is already holding: ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: br_port_slave_changelink+0x3d/0x150 net/bridge/br_netlink.c:1212 which would create a new lock dependency: (&br->lock){+.-.}-{2:2} -> (netdev_rename_lock.seqcount){+.+.}-{0:0} but this new dependency connects a SOFTIRQ-irq-safe lock: (&br->lock){+.-.}-{2:2} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 fs_reclaim_acquire+0xaf/0x140 mm/page_alloc.c:3800 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3890 [inline] slab_alloc_node mm/slub.c:3980 [inline] kmalloc_trace_noprof+0x3d/0x2c0 mm/slub.c:4147 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] class_dir_create_and_add drivers/base/core.c:3255 [inline] get_device_parent+0x2a7/0x410 drivers/base/core.c:3315 device_add+0x325/0xbf0 drivers/base/core.c:3645 netdev_register_kobject+0x17e/0x320 net/core/net-sysfs.c:2136 register_netdevice+0x11d5/0x19e0 net/core/dev.c:10375 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:690 [inline] nsim_create+0x647/0x890 drivers/net/netdevsim/netdev.c:750 __nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1390 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1446 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1498 [inline] nsim_dev_reload_up+0x69b/0x8e0 drivers/net/netdevsim/dev.c:985 devlink_reload+0x478/0x870 net/devlink/dev.c:474 devlink_nl_reload_doit+0xbd6/0xe50 net/devlink/dev.c:586 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 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 to a SOFTIRQ-irq-unsafe lock: (netdev_rename_lock.seqcount){+.+.}-{0:0} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline] do_write_seqcount_begin include/linux/seqlock.h:495 [inline] write_seqlock include/linux/seqlock.h:823 [inline] dev_change_name+0x184/0x920 net/core/dev.c:1229 do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(netdev_rename_lock.seqcount); local_irq_disable(); lock(&br->lock); lock(netdev_rename_lock.seqcount); <Interrupt> lock(&br->lock); *** DEADLOCK *** 3 locks held by syz-executor.2/9449: #0: ffffffff8f5e7448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5e7448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x1180 net/core/rtnetlink.c:6632 #1: ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: br_port_slave_changelink+0x3d/0x150 net/bridge/br_netlink.c:1212 #2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: team_change_rx_flags+0x29/0x330 drivers/net/team/team_core.c:1767 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&br->lock){+.-.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] br_add_if+0xb34/0xef0 net/bridge/br_if.c:682 do_set_master net/core/rtnetlink.c:2701 [inline] do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 IN-SOFTIRQ-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 fs_reclaim_acquire+0xaf/0x140 mm/page_alloc.c:3800 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3890 [inline] slab_alloc_node mm/slub.c:3980 [inline] kmalloc_trace_noprof+0x3d/0x2c0 mm/slub.c:4147 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] class_dir_create_and_add drivers/base/core.c:3255 [inline] get_device_parent+0x2a7/0x410 drivers/base/core.c:3315 device_add+0x325/0xbf0 drivers/base/core.c:3645 netdev_register_kobject+0x17e/0x320 net/core/net-sysfs.c:2136 register_netdevice+0x11d5/0x19e0 net/core/dev.c:10375 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:690 [inline] nsim_create+0x647/0x890 drivers/net/netdevsim/netdev.c:750 __nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1390 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1446 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1498 [inline] nsim_dev_reload_up+0x69b/0x8e0 drivers/net/netdevsim/dev.c:985 devlink_reload+0x478/0x870 net/devlink/dev.c:474 devlink_nl_reload_doit+0xbd6/0xe50 net/devlink/dev.c:586 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 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 INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] br_add_if+0xb34/0xef0 net/bridge/br_if.c:682 do_set_master net/core/rtnetlink.c:2701 [inline] do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 } ... key at: [<ffffffff94b9a1a0>] br_dev_setup.__key+0x0/0x20 the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (netdev_rename_lock.seqcount){+.+.}-{0:0} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline] do_write_seqcount_begin include/linux/seqlock.h:495 [inline] write_seqlock include/linux/seqlock.h:823 [inline] dev_change_name+0x184/0x920 net/core/dev.c:1229 do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 SOFTIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline] do_write_seqcount_begin include/linux/seqlock.h:495 [inline] write_seqlock include/linux/seqlock.h:823 [inline] dev_change_name+0x184/0x920 net/core/dev.c:1229 do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline] do_write_seqcount_begin include/linux/seqlock.h:495 [inline] write_seqlock include/linux/seqlock.h:823 [inline] dev_change_name+0x184/0x920 net/core/dev.c:1229 do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3696 [inline] rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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 INITIAL READ USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] read_seqbegin include/linux/seqlock.h:772 [inline] netdev_copy_name+0x168/0x2c0 net/core/dev.c:949 rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073 rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116 register_netdevice+0x1665/0x19e0 net/core/dev.c:10422 register_netdev+0x3b/0x50 net/core/dev.c:10512 loopback_net_init+0x73/0x150 drivers/net/loopback.c:217 ops_init+0x359/0x610 net/core/net_namespace.c:139 __register_pernet_operations net/core/net_namespace.c:1247 [inline] register_pernet_operations+0x2cb/0x660 net/core/net_namespace.c:1320 register_pernet_device+0x33/0x80 net/core/net_namespace.c:1407 net_dev_init+0xfcd/0x10d0 net/core/dev.c:11956 do_one_initcall+0x248/0x880 init/main.c:1267 do_initcall_level+0x157/0x210 init/main.c:1329 do_initcalls+0x3f/0x80 init/main.c:1345 kernel_init_freeable+0x435/0x5d0 init/main.c:1578 kernel_init+0x1d/0x2b0 init/main.c:1467 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 } ... key at: [<ffffffff8f5de668>] netdev_rename_lock+0x8/0xa0 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] read_seqbegin include/linux/seqlock.h:772 [inline] netdev_copy_name+0x168/0x2c0 net/core/dev.c:949 rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073 rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116 __dev_notify_flags+0xf7/0x400 net/core/dev.c:8816 __dev_set_promiscuity+0x152/0x5a0 net/core/dev.c:8588 dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608 team_change_rx_flags+0x203/0x330 drivers/net/team/team_core.c:1771 dev_change_rx_flags net/core/dev.c:8541 [inline] __dev_set_promiscuity+0x406/0x5a0 net/core/dev.c:8585 dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608 br_port_clear_promisc net/bridge/br_if.c:135 [inline] br_manage_promisc+0x505/0x590 net/bridge/br_if.c:172 nbp_update_port_count net/bridge/br_if.c:242 [inline] br_port_flags_change+0x161/0x1f0 net/bridge/br_if.c:761 br_setport+0xcb5/0x16d0 net/bridge/br_netlink.c:1000 br_port_slave_changelink+0x135/0x150 net/bridge/br_netlink.c:1213 __rtnl_newlink net/core/rtnetlink.c:3689 [inline] rtnl_newlink+0x169f/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 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 stack backtrace: CPU: 0 PID: 9449 Comm: syz-executor.2 Not tainted 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline] check_irq_usage kernel/locking/lockdep.c:2865 [inline] check_prev_add kernel/locking/lockdep.c:3138 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x4de0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] read_seqbegin include/linux/seqlock.h:772 [inline] netdev_copy_name+0x168/0x2c0 net/core/dev.c:949 rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073 rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116 __dev_notify_flags+0xf7/0x400 net/core/dev.c:8816 __dev_set_promiscuity+0x152/0x5a0 net/core/dev.c:8588 dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608 team_change_rx_flags+0x203/0x330 drivers/net/team/team_core.c:1771 dev_change_rx_flags net/core/dev.c:8541 [inline] __dev_set_promiscuity+0x406/0x5a0 net/core/dev.c:8585 dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608 br_port_clear_promisc net/bridge/br_if.c:135 [inline] br_manage_promisc+0x505/0x590 net/bridge/br_if.c:172 nbp_update_port_count net/bridge/br_if.c:242 [inline] br_port_flags_change+0x161/0x1f0 net/bridge/br_if.c:761 br_setport+0xcb5/0x16d0 net/bridge/br_netlink.c:1000 br_port_slave_changelink+0x135/0x150 net/bridge/br_netlink.c:1213 __rtnl_newlink net/core/rtnetlink.c:3689 [inline] rtnl_newlink+0x169f/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 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 RIP: 0033:0x7f3b3047cf29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3b311740c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f3b305b4050 RCX: 00007f3b3047cf29 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008 RBP: 00007f3b304ec074 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f3b305b4050 R15: 00007ffca2f3dc68 </TASK> Fixes: 0840556e5a3a ("net: Protect dev->name by seqlock.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> --- net/core/dev.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)