============================================ WARNING: possible recursive locking detected 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Not tainted -------------------------------------------- syz-executor/5860 is trying to acquire lock: ffff88805cf9af30 (&hsr->seqnr_lock){+.-.}-{3:3} , at: spin_lock_bh include/linux/spinlock.h:356 [inline] , at: hsr_dev_xmit+0x18a/0x210 net/hsr/hsr_device.c:234 but task is already holding lock: ffff888078b6cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888078b6cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x27c/0xcc0 net/hsr/hsr_device.c:317 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&hsr->seqnr_lock); lock(&hsr->seqnr_lock); *** DEADLOCK *** May be due to missing lock nesting notation 15 locks held by syz-executor/5860: #0: ffffffff8ebefad0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:637 [inline] #0: ffffffff8ebefad0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1675 [inline] #0: ffffffff8ebefad0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x27c/0x1e80 kernel/fork.c:1724 #1: ffff8880252bc620 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline] #1: ffff8880252bc620 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap kernel/fork.c:638 [inline] #1: ffff8880252bc620 (&mm->mmap_lock){++++}-{4:4}, at: dup_mm kernel/fork.c:1675 [inline] #1: ffff8880252bc620 (&mm->mmap_lock){++++}-{4:4}, at: copy_mm+0x29a/0x1e80 kernel/fork.c:1724 #2: ffff888024ba1560 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:113 [inline] #2: ffff888024ba1560 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap kernel/fork.c:647 [inline] #2: ffff888024ba1560 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mm kernel/fork.c:1675 [inline] #2: ffff888024ba1560 (&mm->mmap_lock/1){+.+.}-{4:4}, at: copy_mm+0x3dc/0x1e80 kernel/fork.c:1724 #3: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:287 #4: ffff888031f64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #4: ffff888031f64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:375 #5: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #5: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #5: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:287 #6: ffff88805f7c42b8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1119 [inline] #6: ffff88805f7c42b8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x726/0x85b0 mm/memory.c:1255 #7: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #7: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #7: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: page_ext_get+0x20/0x2a0 mm/page_ext.c:525 #8: ffffc90000007c00 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1790 #9: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #9: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #9: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: hsr_announce+0xaa/0x3a0 net/hsr/hsr_device.c:406 #10: ffff888078b6cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #10: ffff888078b6cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x27c/0xcc0 net/hsr/hsr_device.c:317 #11: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #11: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #11: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0xb6/0x2ac0 net/hsr/hsr_forward.c:723 #12: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #12: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:901 [inline] #12: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2f4/0x3f50 net/core/dev.c:4359 #13: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #13: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #13: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x21d/0x1b40 net/bridge/br_device.c:50 #14: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #14: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:901 [inline] #14: ffffffff8eb3c8c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2f4/0x3f50 net/core/dev.c:4359 stack backtrace: CPU: 0 UID: 0 PID: 5860 Comm: syz-executor Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __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] hsr_dev_xmit+0x18a/0x210 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3606 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3168 [inline] br_dev_queue_push_xmit+0x726/0x900 net/bridge/br_forward.c:53 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190 br_flood+0x2e4/0x660 net/bridge/br_forward.c:236 br_dev_xmit+0x1202/0x1b40 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3606 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3168 [inline] hsr_xmit net/hsr/hsr_forward.c:430 [inline] hsr_forward_do net/hsr/hsr_forward.c:571 [inline] hsr_forward_skb+0x171c/0x2ac0 net/hsr/hsr_forward.c:728 send_hsr_supervision_frame+0x63b/0xcc0 net/hsr/hsr_device.c:351 hsr_announce+0x1f8/0x3a0 net/hsr/hsr_device.c:408 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793 expire_timers kernel/time/timer.c:1844 [inline] __run_timers kernel/time/timer.c:2418 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430 run_timer_base kernel/time/timer.c:2439 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:655 irq_exit_rcu+0x9/0x30 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 da 25 8f 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003e7f060 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007cfe18 RCX: ffff888035d6c6d8 RDX: dffffc0000000000 RSI: ffffffff8c2ae4e0 RDI: ffffffff8c820860 RBP: ffffc90003e7f1b8 R08: ffffffff94546887 R09: 1ffffffff28a8d10 R10: dffffc0000000000 R11: fffffbfff28a8d11 R12: 1ffff920007cfe14 R13: dffffc0000000000 R14: ffffc90003e7f0c0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 page_table_check_set+0x4f/0x540 mm/page_table_check.c:114 __page_table_check_ptes_set+0x30f/0x410 mm/page_table_check.c:225 page_table_check_ptes_set include/linux/page_table_check.h:74 [inline] set_ptes include/linux/pgtable.h:267 [inline] __copy_present_ptes mm/memory.c:969 [inline] copy_present_ptes mm/memory.c:1052 [inline] copy_pte_range mm/memory.c:1167 [inline] copy_pmd_range+0x4785/0x85b0 mm/memory.c:1255 copy_pud_range mm/memory.c:1292 [inline] copy_p4d_range mm/memory.c:1316 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1414 dup_mmap kernel/fork.c:746 [inline] dup_mm kernel/fork.c:1675 [inline] copy_mm+0x1117/0x1e80 kernel/fork.c:1724 copy_process+0x1845/0x3d50 kernel/fork.c:2375 kernel_clone+0x226/0x8f0 kernel/fork.c:2787 __do_sys_clone kernel/fork.c:2930 [inline] __se_sys_clone kernel/fork.c:2914 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2914 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: 0033:0x7f5244975093 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffd9e8ba8e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5244975093 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055558fed07d0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000018894 R14: 000000000001886b R15: 00007ffd9e8baa70 ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 da 25 8f 00 call 0x8f25e6 c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 85 01 00 00 jne 0x19c 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25