======================================
| [   52.496992][  T644] ==================================================================
| [ 52.497268][ T644] BUG: KASAN: null-ptr-deref in nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
| [   52.497503][  T644] Read of size 4 at addr 0000000000000068 by task ip/644
| [   52.497693][  T644]
[   52.497780][  T644] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   52.497782][  T644] Call Trace:
[   52.497784][  T644]  <TASK>
[ 52.497786][ T644] dump_stack_lvl (lib/dump_stack.c:123) 
[ 52.497792][ T644] kasan_report (mm/kasan/report.c:636) 
[ 52.497797][ T644] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 52.497803][ T644] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 52.497807][ T644] nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 52.497812][ T644] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[ 52.497816][ T644] ? __nla_validate_parse (lib/nlattr.c:638) 
[ 52.497826][ T644] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[ 52.497832][ T644] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 52.497838][ T644] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 52.497843][ T644] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 52.497861][ T644] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[ 52.497866][ T644] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 52.497870][ T644] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[ 52.497875][ T644] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 52.497878][ T644] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 52.497881][ T644] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 52.497886][ T644] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 52.497890][ T644] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[ 52.497894][ T644] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 52.497899][ T644] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[ 52.497906][ T644] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[ 52.497909][ T644] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333) 
[ 52.497913][ T644] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[ 52.497916][ T644] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[ 52.497920][ T644] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 52.497924][ T644] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[ 52.497928][ T644] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[ 52.497934][ T644] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[ 52.497940][ T644] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[ 52.497944][ T644] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[ 52.497950][ T644] ___sys_sendmsg (net/socket.c:2619) 
[ 52.497954][ T644] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[ 52.497956][ T644] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 52.497960][ T644] ? __pfx_handle_pte_fault (mm/memory.c:5864) 
[ 52.497966][ T644] ? __handle_mm_fault (mm/memory.c:6050) 
[ 52.497970][ T644] ? __pfx___handle_mm_fault (mm/memory.c:5959) 
[ 52.497972][ T644] ? mt_find (lib/maple_tree.c:6909) 
[ 52.497978][ T644] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 52.497982][ T644] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 52.497984][ T644] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) 
[ 52.497990][ T644] __sys_sendmsg (net/socket.c:2649) 
[ 52.497993][ T644] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[ 52.497998][ T644] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) 
[ 52.498003][ T644] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 52.498007][ T644] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   52.498012][  T644] RIP: 0033:0x7f5b59e549a7
[ 52.498016][ T644] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0a 00                	or     (%rax),%al
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[   52.498019][  T644] RSP: 002b:00007ffd5e645008 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   52.498023][  T644] RAX: ffffffffffffffda RBX: 00007ffd5e645b90 RCX: 00007f5b59e549a7
[   52.498025][  T644] RDX: 0000000000000000 RSI: 00007ffd5e645070 RDI: 0000000000000005
[   52.498027][  T644] RBP: 00007ffd5e645530 R08: 0000000000000002 R09: 0000000000000000
[   52.498028][  T644] R10: 00007f5b59d0d708 R11: 0000000000000246 R12: 0000000000000001
[   52.498030][  T644] R13: 0000000067da3cd4 R14: 0000000000498600 R15: 00007ffd5e646992
| [   52.508666][  T644] Disabling lock debugging due to kernel taint
| [   52.508870][  T644] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [   52.509229][  T644] KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
| [   52.509700][  T644] Tainted: [B]=BAD_PAGE
[   52.509811][  T644] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 52.509999][ T644] RIP: 0010:nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 52.510189][ T644] Code: 5c 09 00 00 45 3b 7e 60 72 c0 76 06 49 83 c6 08 eb bc 4d 8d 7e 68 be 04 00 00 00 4c 89 ff e8 84 19 2f fe 4c 89 f8 48 c1 e8 03 <42> 0f b6 14 20 4c 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85
All code
========
   0:	5c                   	pop    %rsp
   1:	09 00                	or     %eax,(%rax)
   3:	00 45 3b             	add    %al,0x3b(%rbp)
   6:	7e 60                	jle    0x68
   8:	72 c0                	jb     0xffffffffffffffca
   a:	76 06                	jbe    0x12
   c:	49 83 c6 08          	add    $0x8,%r14
  10:	eb bc                	jmp    0xffffffffffffffce
  12:	4d 8d 7e 68          	lea    0x68(%r14),%r15
  16:	be 04 00 00 00       	mov    $0x4,%esi
  1b:	4c 89 ff             	mov    %r15,%rdi
  1e:	e8 84 19 2f fe       	call   0xfffffffffe2f19a7
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
  2a:*	42 0f b6 14 20       	movzbl (%rax,%r12,1),%edx		<-- trapping instruction
  2f:	4c 89 f8             	mov    %r15,%rax
  32:	83 e0 07             	and    $0x7,%eax
  35:	83 c0 03             	add    $0x3,%eax
  38:	38 d0                	cmp    %dl,%al
  3a:	7c 08                	jl     0x44
  3c:	84 d2                	test   %dl,%dl
  3e:	0f                   	.byte 0xf
  3f:	85                   	.byte 0x85

Code starting with the faulting instruction
===========================================
   0:	42 0f b6 14 20       	movzbl (%rax,%r12,1),%edx
   5:	4c 89 f8             	mov    %r15,%rax
   8:	83 e0 07             	and    $0x7,%eax
   b:	83 c0 03             	add    $0x3,%eax
   e:	38 d0                	cmp    %dl,%al
  10:	7c 08                	jl     0x1a
  12:	84 d2                	test   %dl,%dl
  14:	0f                   	.byte 0xf
  15:	85                   	.byte 0x85
[   52.510701][  T644] RSP: 0018:ffffc900015273c8 EFLAGS: 00010202
[   52.510887][  T644] RAX: 000000000000000d RBX: ffff88800e0aaa68 RCX: ffffffff91253d8a
[   52.511112][  T644] RDX: fffffbfff2ca2491 RSI: 0000000000000008 RDI: ffffffff96512480
[   52.511330][  T644] RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff2ca2490
[   52.511545][  T644] R10: ffffffff96512487 R11: 205d343436542020 R12: dffffc0000000000
[   52.511763][  T644] R13: ffff8880059ff240 R14: 0000000000000000 R15: 0000000000000068
[   52.511986][  T644] FS:  00007f5b59c48800(0000) GS:ffff88802f400000(0000) knlGS:0000000000000000
[   52.512238][  T644] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   52.512423][  T644] CR2: 00007f5b59ea3ac0 CR3: 0000000001ff8002 CR4: 0000000000772ef0
[   52.512639][  T644] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   52.512863][  T644] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   52.513083][  T644] PKRU: 55555554
[   52.513194][  T644] Call Trace:
[   52.513304][  T644]  <TASK>
[ 52.513384][ T644] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 52.513500][ T644] ? exc_general_protection (arch/x86/kernel/traps.c:751 arch/x86/kernel/traps.c:693) 
[ 52.513653][ T644] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 52.513803][ T644] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:605) 
[ 52.513922][ T644] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 52.514069][ T644] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 52.514218][ T644] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[ 52.514362][ T644] ? __nla_validate_parse (lib/nlattr.c:638) 
[ 52.514511][ T644] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[ 52.514659][ T644] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 52.514808][ T644] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 52.514921][ T644] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 52.515074][ T644] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[ 52.515225][ T644] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 52.515369][ T644] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[ 52.515514][ T644] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 52.515662][ T644] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 52.515807][ T644] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 52.515922][ T644] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 52.516067][ T644] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[ 52.516228][ T644] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 52.516376][ T644] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[ 52.516524][ T644] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[ 52.516668][ T644] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333) 
[ 52.516813][ T644] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[ 52.516969][ T644] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[ 52.517113][ T644] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 52.517258][ T644] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[ 52.517406][ T644] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[ 52.517555][ T644] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[ 52.517703][ T644] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[ 52.517849][ T644] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[ 52.518039][ T644] ___sys_sendmsg (net/socket.c:2619) 
[ 52.518185][ T644] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[ 52.518330][ T644] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 52.518476][ T644] ? __pfx_handle_pte_fault (mm/memory.c:5864) 
[ 52.518625][ T644] ? __handle_mm_fault (mm/memory.c:6050) 
[ 52.518771][ T644] ? __pfx___handle_mm_fault (mm/memory.c:5959) 
[ 52.518916][ T644] ? mt_find (lib/maple_tree.c:6909) 
[ 52.519036][ T644] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 52.519181][ T644] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 52.519326][ T644] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) 
[ 52.519472][ T644] __sys_sendmsg (net/socket.c:2649) 
[ 52.519616][ T644] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[ 52.519761][ T644] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) 
[ 52.519910][ T644] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 52.520061][ T644] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   52.520241][  T644] RIP: 0033:0x7f5b59e549a7
[ 52.520393][ T644] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0a 00                	or     (%rax),%al
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[   52.520901][  T644] RSP: 002b:00007ffd5e645008 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   52.521128][  T644] RAX: ffffffffffffffda RBX: 00007ffd5e645b90 RCX: 00007f5b59e549a7
[   52.521346][  T644] RDX: 0000000000000000 RSI: 00007ffd5e645070 RDI: 0000000000000005
[   52.521564][  T644] RBP: 00007ffd5e645530 R08: 0000000000000002 R09: 0000000000000000
[   52.521781][  T644] R10: 00007f5b59d0d708 R11: 0000000000000246 R12: 0000000000000001


Finger prints:
nexthop_create_group:rtm_new_nexthop:rtnetlink_rcv_msg:netlink_rcv_skb:netlink_unicast
kasan_report:kasan_check_range:nexthop_create_group:rtm_new_nexthop:rtnetlink_rcv_msg