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BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
BUG: KASAN: null-ptr-deref in atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline]
BUG: KASAN: null-ptr-deref in atomic_add_unless include/linux/atomic-fallback.h:1111 [inline]
BUG: KASAN: null-ptr-deref in atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline]
BUG: KASAN: null-ptr-deref in dst_hold_safe include/net/dst.h:308 [inline]
BUG: KASAN: null-ptr-deref in ip6_hold_safe+0xb3/0x3a0 net/ipv6/route.c:1023
Read of size 4 at addr 00000000000001a5 by task syz-executor.5/20794

CPU: 1 PID: 20794 Comm: syz-executor.5 Not tainted 5.1.0-rc3+ #156
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 kasan_report.cold+0x5/0x40 mm/kasan/report.c:321
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 kasan_check_read+0x11/0x20 mm/kasan/common.c:102
 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
 atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline]
 atomic_add_unless include/linux/atomic-fallback.h:1111 [inline]
 atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline]
 dst_hold_safe include/net/dst.h:308 [inline]
 ip6_hold_safe+0xb3/0x3a0 net/ipv6/route.c:1023
 rt6_get_pcpu_route net/ipv6/route.c:1245 [inline]
 ip6_pol_route+0x348/0x1040 net/ipv6/route.c:1906
 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2082
 fib6_rule_lookup+0x269/0x560 net/ipv6/fib6_rules.c:122
 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2111
 ip6_dst_lookup_tail+0x1124/0x1b30 net/ipv6/ip6_output.c:993
 ip6_dst_lookup+0x4d/0x70 net/ipv6/ip6_output.c:1073
 icmpv6_route_lookup+0x346/0x4d0 net/ipv6/icmp.c:378
 icmp6_send+0x14ac/0x21f0 net/ipv6/icmp.c:557
 icmpv6_send+0xee/0x230 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0x2b/0x530 net/ipv6/route.c:2245
 dst_link_failure include/net/dst.h:427 [inline]
 ip6_tnl_xmit+0x447/0x3500 net/ipv6/ip6_tunnel.c:1227
 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1383 [inline]
 ip6_tnl_start_xmit+0x867/0x1ce0 net/ipv6/ip6_tunnel.c:1409
 __netdev_start_xmit include/linux/netdevice.h:4411 [inline]
 netdev_start_xmit include/linux/netdevice.h:4420 [inline]
 xmit_one net/core/dev.c:3278 [inline]
 dev_hard_start_xmit+0x1b2/0x980 net/core/dev.c:3294
 __dev_queue_xmit+0x271d/0x3060 net/core/dev.c:3864
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3897
 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0xb7c/0x2550 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 rawv6_send_hdrinc net/ipv6/raw.c:689 [inline]
 rawv6_sendmsg+0x1dd5/0x35e0 net/ipv6/raw.c:933
 inet_sendmsg+0x147/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 ___sys_sendmsg+0x806/0x930 net/socket.c:2260
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2298
 __do_sys_sendmsg net/socket.c:2307 [inline]
 __se_sys_sendmsg net/socket.c:2305 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2305
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4582b9
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb0a83cfc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004582b9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb0a83d06d4
R13: 00000000004c5279 R14: 00000000004d93f8 R15: 00000000ffffffff
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