================================================================== BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x196a/0x1b30 net/ipv6/ip6_output.c:1010 Read of size 8 at addr ffff8880a39178ff by task syz-executor.3/32494 CPU: 0 PID: 32494 Comm: syz-executor.3 Not tainted 5.2.0-rc1+ #6 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:1010 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1094 ip6_datagram_dst_update+0x5d8/0xc20 net/ipv6/datagram.c:91 __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:250 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:273 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:575 __sys_connect+0x264/0x330 net/socket.c:1840 __do_sys_connect net/socket.c:1851 [inline] __se_sys_connect net/socket.c:1848 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1848 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:00007f89a7616c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 000000000000001c RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f89a76176d4 R13: 00000000004bf74d R14: 00000000004d0c18 R15: 00000000ffffffff Allocated by task 10280: 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_output+0x54/0x70 net/ipv6/route.c:2204 fib6_rule_lookup+0x279/0x5a0 net/ipv6/fib6_rules.c:120 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2233 ip6_route_output include/net/ip6_route.h:89 [inline] ip6_dst_lookup_tail+0xd10/0x1b30 net/ipv6/ip6_output.c:966 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1094 ip6_datagram_dst_update+0x5d8/0xc20 net/ipv6/datagram.c:91 __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:250 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:273 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:575 __sys_connect+0x264/0x330 net/socket.c:1840 __do_sys_connect net/socket.c:1851 [inline] __se_sys_connect net/socket.c:1848 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1848 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9486: 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 ffff8880a39177c0 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 [ffff8880a39177c0, ffff8880a39178a0) The buggy address belongs to the page: page:ffffea00028e45c0 refcount:1 mapcount:0 mapping:ffff8880a0519500 index:0xffff8880a3917400 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00022288c8 ffffea000217d4c8 ffff8880a0519500 raw: ffff8880a3917400 ffff8880a3917040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a3917780: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8880a3917800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a3917880: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a3917900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a3917980: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc 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