===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- dhcpcd-run-hook/5941 is trying to release lock (rcu_read_lock) at: [] rcu_read_unlock+0x2d/0xb0 include/linux/rcupdate.h:867 but there are no more locks to release! other info that might help us debug this: 1 lock held by dhcpcd-run-hook/5941: #0: ffff8880440f3d48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 stack backtrace: CPU: 2 UID: 0 PID: 5941 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_unlock_imbalance_bug.part.0+0xfb/0x106 kernel/locking/lockdep.c:5298 print_unlock_imbalance_bug kernel/locking/lockdep.c:5278 [inline] __lock_release kernel/locking/lockdep.c:5537 [inline] lock_release kernel/locking/lockdep.c:5889 [inline] lock_release+0x28d/0x310 kernel/locking/lockdep.c:5875 rcu_read_unlock+0x32/0xb0 include/linux/rcupdate.h:867 pte_unmap include/linux/pgtable.h:117 [inline] wp_page_copy mm/memory.c:3960 [inline] do_wp_page+0x13d7/0x4350 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f7501c33f87 Code: 5c 25 28 49 8b 57 10 48 85 db 74 27 8b 74 24 0c 23 73 08 44 39 f6 75 16 48 39 c2 75 05 e8 62 ff ff ff 48 8b 53 10 48 83 c0 08 <48> 89 50 f8 48 8b 1b eb d0 49 83 c4 08 49 81 fc 38 01 00 00 75 be RSP: 002b:00007ffd29921270 EFLAGS: 00010212 RAX: 00005645dcc81140 RBX: 00005645dcc716d0 RCX: 0000000000000002 RDX: 00007ffd29925f83 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000008 R13: 00005645dcc70e60 R14: 0000000000000001 R15: 00005645dcc70c30 ------------[ cut here ]------------ rrln < 0 || rrln > RCU_NEST_PMAX WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock kernel/rcu/tree_plugin.h:443 [inline], CPU#3: dhcpcd-run-hook/5941 WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock+0x235/0x5e0 kernel/rcu/tree_plugin.h:430, CPU#3: dhcpcd-run-hook/5941 Modules linked in: CPU: 3 UID: 0 PID: 5941 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__rcu_read_unlock kernel/rcu/tree_plugin.h:443 [inline] RIP: 0010:__rcu_read_unlock+0x235/0x5e0 kernel/rcu/tree_plugin.h:430 Code: 74 11 c7 45 58 01 00 00 00 bf 09 00 00 00 e8 12 a5 da ff e8 9d e2 22 00 9c 58 f6 c4 02 0f 85 dd 02 00 00 fb e9 57 fe ff ff 90 <0f> 0b 90 5b 5d 41 5c 41 5d 41 5e 41 5f e9 d9 14 ad 09 e8 44 64 87 RSP: 0000:ffffc900049c7af0 EFLAGS: 00010286 RAX: 00000000ffffffff RBX: ffff888029ec4a00 RCX: ffffffff81e80bfe RDX: 0000000000000000 RSI: ffffffff8df2fec2 RDI: ffff888029ec4ec4 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000080000000 R11: 0000000000000012 R12: ffff88802ad93408 R13: ffffea0000ad7800 R14: 0000000000000000 R15: ffffea0000ad7800 FS: 00007f7501945c80(0000) GS:ffff8880973e2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005645dcc70950 CR3: 00000000297d6000 CR4: 0000000000352ef0 Call Trace: pte_unmap include/linux/pgtable.h:117 [inline] wp_page_copy mm/memory.c:3960 [inline] do_wp_page+0x13d7/0x4350 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f7501c33f87 Code: 5c 25 28 49 8b 57 10 48 85 db 74 27 8b 74 24 0c 23 73 08 44 39 f6 75 16 48 39 c2 75 05 e8 62 ff ff ff 48 8b 53 10 48 83 c0 08 <48> 89 50 f8 48 8b 1b eb d0 49 83 c4 08 49 81 fc 38 01 00 00 75 be RSP: 002b:00007ffd29921270 EFLAGS: 00010212 RAX: 00005645dcc81140 RBX: 00005645dcc716d0 RCX: 0000000000000002 RDX: 00007ffd29925f83 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000008 R13: 00005645dcc70e60 R14: 0000000000000001 R15: 00005645dcc70c30