======================================
| [  761.669922][T12252] ==================================================================
| [761.670193][T12252] 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) 
| [  761.670435][T12252] Read of size 4 at addr 0000000000000068 by task ip/12252
| [  761.670661][T12252]
[  761.670748][T12252] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  761.670751][T12252] Call Trace:
[  761.670754][T12252]  <TASK>
[761.670756][T12252] dump_stack_lvl (lib/dump_stack.c:123) 
[761.670763][T12252] kasan_report (mm/kasan/report.c:636) 
[761.670772][T12252] ? 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) 
[761.670778][T12252] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[761.670782][T12252] 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) 
[761.670789][T12252] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[761.670792][T12252] ? __nla_validate_parse (lib/nlattr.c:638) 
[761.670802][T12252] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[761.670807][T12252] ? 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) 
[761.670815][T12252] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[761.670818][T12252] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[761.670832][T12252] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[761.670838][T12252] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[761.670842][T12252] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[761.670846][T12252] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[761.670849][T12252] ? 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) 
[761.670853][T12252] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[761.670857][T12252] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[761.670861][T12252] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[761.670866][T12252] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[761.670870][T12252] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[761.670878][T12252] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[761.670883][T12252] ? 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) 
[761.670888][T12252] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[761.670892][T12252] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[761.670895][T12252] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[761.670901][T12252] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[761.670905][T12252] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[761.670911][T12252] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[761.670918][T12252] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[761.670921][T12252] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[761.670929][T12252] ___sys_sendmsg (net/socket.c:2619) 
[761.670931][T12252] ? 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) 
[761.670935][T12252] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[761.670939][T12252] ? hlock_class (kernel/locking/lockdep.c:225) 
[761.670945][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[761.670953][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[761.670958][T12252] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[761.670962][T12252] ? __lock_release (kernel/locking/lockdep.c:5527) 
[761.670966][T12252] __sys_sendmsg (net/socket.c:2649) 
[761.670969][T12252] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[761.670974][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[761.670980][T12252] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[761.670984][T12252] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[  761.670990][T12252] RIP: 0033:0x7f4cd9dba9a7
[ 761.670994][T12252] 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)
[  761.670997][T12252] RSP: 002b:00007ffc4e276d88 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  761.671002][T12252] RAX: ffffffffffffffda RBX: 00007ffc4e2778f0 RCX: 00007f4cd9dba9a7
[  761.671004][T12252] RDX: 0000000000000000 RSI: 00007ffc4e276df0 RDI: 0000000000000005
[  761.671006][T12252] RBP: 00007ffc4e2772b0 R08: 000000003814e910 R09: 0000000000000000
[  761.671008][T12252] R10: 00007f4cd9c73708 R11: 0000000000000246 R12: 000000003814e918
[  761.671010][T12252] R13: 0000000067da3aeb R14: 0000000000498600 R15: 000000003814e910
| [  761.683823][T12252] Disabling lock debugging due to kernel taint
| [  761.684157][T12252] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [  761.684658][T12252] KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
| [  761.685322][T12252] Tainted: [B]=BAD_PAGE
[  761.685481][T12252] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[761.685745][T12252] 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) 
[ 761.686021][T12252] 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 34 7e 32 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 34 7e 32 fe       	call   0xfffffffffe327e57
  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
[  761.686741][T12252] RSP: 0018:ffffc90000cf73c8 EFLAGS: 00010202
[  761.687007][T12252] RAX: 000000000000000d RBX: ffff88800e5c34e8 RCX: ffffffffb6451d8a
[  761.687318][T12252] RDX: fffffbfff76df891 RSI: 0000000000000008 RDI: ffffffffbb6fc480
[  761.687624][T12252] RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff76df890
[  761.687917][T12252] R10: ffffffffbb6fc487 R11: 205d323532323154 R12: dffffc0000000000
[  761.688210][T12252] R13: ffff888004e9d540 R14: 0000000000000000 R15: 0000000000000068
[  761.688446][T12252] FS:  00007f4cd9bae800(0000) GS:ffff88802f400000(0000) knlGS:0000000000000000
[  761.688676][T12252] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  761.688845][T12252] CR2: 00007f4cd9e0a423 CR3: 000000000948e002 CR4: 0000000000772ef0
[  761.689042][T12252] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  761.689266][T12252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  761.689473][T12252] PKRU: 55555554
[  761.689574][T12252] Call Trace:
[  761.689676][T12252]  <TASK>
[761.689749][T12252] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[761.689857][T12252] ? exc_general_protection (arch/x86/kernel/traps.c:751 arch/x86/kernel/traps.c:693) 
[761.689999][T12252] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[761.690138][T12252] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:605) 
[761.690268][T12252] ? 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) 
[761.690404][T12252] ? 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) 
[761.690538][T12252] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[761.690669][T12252] ? __nla_validate_parse (lib/nlattr.c:638) 
[761.690805][T12252] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[761.690948][T12252] ? 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) 
[761.691089][T12252] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[761.691199][T12252] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[761.691347][T12252] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[761.691483][T12252] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[761.691618][T12252] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[761.691750][T12252] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[761.691886][T12252] ? 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) 
[761.692016][T12252] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[761.692124][T12252] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[761.692268][T12252] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[761.692398][T12252] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[761.692528][T12252] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[761.692663][T12252] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[761.692795][T12252] ? 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) 
[761.692926][T12252] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[761.693062][T12252] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[761.693196][T12252] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[761.693356][T12252] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[761.693489][T12252] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[761.693626][T12252] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[761.693776][T12252] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[761.693904][T12252] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[761.694078][T12252] ___sys_sendmsg (net/socket.c:2619) 
[761.694219][T12252] ? 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) 
[761.694351][T12252] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[761.694481][T12252] ? hlock_class (kernel/locking/lockdep.c:225) 
[761.694612][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[761.694747][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[761.694877][T12252] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[761.695023][T12252] ? __lock_release (kernel/locking/lockdep.c:5527) 
[761.695153][T12252] __sys_sendmsg (net/socket.c:2649) 
[761.695294][T12252] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[761.695426][T12252] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[761.695556][T12252] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[761.695688][T12252] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[  761.695850][T12252] RIP: 0033:0x7f4cd9dba9a7
[ 761.695996][T12252] 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)
[  761.696469][T12252] RSP: 002b:00007ffc4e276d88 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  761.696668][T12252] RAX: ffffffffffffffda RBX: 00007ffc4e2778f0 RCX: 00007f4cd9dba9a7
[  761.696870][T12252] RDX: 0000000000000000 RSI: 00007ffc4e276df0 RDI: 0000000000000005
[  761.697066][T12252] RBP: 00007ffc4e2772b0 R08: 000000003814e910 R09: 0000000000000000
[  761.697288][T12252] R10: 00007f4cd9c73708 R11: 0000000000000246 R12: 000000003814e918


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