================================================================== BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x196a/0x1b30 net/ipv6/ip6_output.c:1063 Read of size 8 at addr ffff88809d0b063f by task syz-executor.3/16974 CPU: 1 PID: 16974 Comm: syz-executor.3 Not tainted 5.2.0-rc1+ #8 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 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 ip6_dst_lookup_tail+0x196a/0x1b30 net/ipv6/ip6_output.c:1063 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1147 ip6_sk_dst_lookup_flow net/ipv6/ip6_output.c:1185 [inline] ip6_sk_dst_lookup_flow+0x62a/0xb90 net/ipv6/ip6_output.c:1175 udpv6_sendmsg+0x17ad/0x28d0 net/ipv6/udp.c:1452 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:802 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:671 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2292 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2387 __do_sys_sendmmsg net/socket.c:2416 [inline] __se_sys_sendmmsg net/socket.c:2413 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2413 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f853200ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459279 RDX: 00000000000004ff RSI: 00000000200092c0 RDI: 0000000000000003 RBP: 000000000075bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f853200f6d4 R13: 00000000004c65fc R14: 00000000004db280 R15: 00000000ffffffff Allocated by task 16591: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488 dst_alloc+0x10e/0x200 net/core/dst.c:93 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:356 ip6_rt_pcpu_alloc net/ipv6/route.c:1257 [inline] rt6_make_pcpu_route net/ipv6/route.c:1287 [inline] ip6_pol_route+0x656/0x1050 net/ipv6/route.c:2031 ip6_pol_route_input+0x65/0x80 net/ipv6/route.c:2047 fib6_rule_lookup+0x133/0x5a0 net/ipv6/fib6_rules.c:116 ip6_route_input_lookup+0xb7/0xd0 net/ipv6/route.c:2059 ip6_route_input+0x5e2/0x9e0 net/ipv6/route.c:2194 ip6_rcv_finish_core.isra.0+0x174/0x590 net/ipv6/ip6_input.c:67 ip6_rcv_finish+0x17a/0x310 net/ipv6/ip6_input.c:78 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:276 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:4990 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5104 process_backlog+0x206/0x750 net/core/dev.c:5944 napi_poll net/core/dev.c:6367 [inline] net_rx_action+0x4f5/0x1070 net/core/dev.c:6433 __do_softirq+0x25c/0x94c kernel/softirq.c:293 Freed by task 3034: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 dst_destroy+0x29e/0x3c0 net/core/dst.c:129 dst_destroy_rcu+0x16/0x19 net/core/dst.c:142 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c kernel/softirq.c:293 The buggy address belongs to the object at ffff88809d0b0500 which belongs to the cache ip6_dst_cache of size 224 The buggy address is located 95 bytes to the right of 224-byte region [ffff88809d0b0500, ffff88809d0b05e0) The buggy address belongs to the page: page:ffffea0002742c00 refcount:1 mapcount:0 mapping:ffff88821665a000 index:0xffff88809d0b08c0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002a5aa48 ffffea00029d9288 ffff88821665a000 raw: ffff88809d0b08c0 ffff88809d0b0000 000000010000000a 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809d0b0500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809d0b0580: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff88809d0b0600: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ^ ffff88809d0b0680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809d0b0700: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================