===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- sshd-session/5719 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 sshd-session/5719: #0: ffff88802a9ebe88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 stack backtrace: CPU: 3 UID: 0 PID: 5719 Comm: sshd-session 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: 0033:0x7fe39af83418 Code: fe ff ff 0f 1f 80 00 00 00 00 48 85 f6 0f 84 af 00 00 00 41 f6 85 56 03 00 00 20 0f 85 a1 00 00 00 49 8b 45 60 48 85 c0 74 04 <48> 01 70 08 49 8b 45 58 48 85 c0 74 04 48 01 70 08 49 8b 45 68 48 RSP: 002b:00007ffee61724e0 EFLAGS: 00010202 RAX: 00007fe39af1fc70 RBX: 0000000000000030 RCX: 00007fe39af72b60 RDX: 00007fe39af1fdc0 RSI: 00007fe39ae2b000 RDI: 000000006fffffff RBP: 00007ffee6172630 R08: 0000000000000006 R09: 00000000effffef5 R10: 0000000070000029 R11: 00007ffee6172718 R12: 00007ffee6172390 R13: 00007fe39af72b20 R14: 00007ffee61726d0 R15: 00007fe39af24750 ------------[ 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: sshd-session/5719 WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock+0x235/0x5e0 kernel/rcu/tree_plugin.h:430, CPU#3: sshd-session/5719 Modules linked in: CPU: 3 UID: 0 PID: 5719 Comm: sshd-session 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 92 a3 da ff e8 fd de 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 e0 9c 09 e8 44 60 87