================================================================== BUG: KASAN: slab-out-of-bounds in fib6_drop_pcpu_from net/ipv6/ip6_fib.c:925 [inline] BUG: KASAN: slab-out-of-bounds in fib6_purge_rt+0x1b3/0x5e0 net/ipv6/ip6_fib.c:937 Write of size 8 at addr ffff88809bde23e6 by task syz-executor.3/5265 CPU: 1 PID: 5265 Comm: syz-executor.3 Not tainted 5.2.0-rc1+ #29 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 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_write+0x14/0x20 mm/kasan/common.c:100 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:925 [inline] fib6_purge_rt+0x1b3/0x5e0 net/ipv6/ip6_fib.c:937 fib6_del_route net/ipv6/ip6_fib.c:1812 [inline] fib6_del+0xac2/0x10a0 net/ipv6/ip6_fib.c:1843 fib6_clean_node+0x3a5/0x590 net/ipv6/ip6_fib.c:2005 fib6_walk_continue+0x4a9/0x8e0 net/ipv6/ip6_fib.c:1927 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:1975 fib6_clean_tree+0xe0/0x120 net/ipv6/ip6_fib.c:2054 __fib6_clean_all+0x118/0x2a0 net/ipv6/ip6_fib.c:2070 fib6_clean_all+0x2b/0x40 net/ipv6/ip6_fib.c:2081 rt6_sync_down_dev+0x134/0x150 net/ipv6/route.c:4169 rt6_disable_ip+0x27/0x5f0 net/ipv6/route.c:4174 addrconf_ifdown+0xa2/0x1220 net/ipv6/addrconf.c:3709 addrconf_notify+0x5db/0x2270 net/ipv6/addrconf.c:3634 notifier_call_chain+0xc2/0x230 kernel/notifier.c:95 __raw_notifier_call_chain kernel/notifier.c:396 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:403 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1753 call_netdevice_notifiers_extack net/core/dev.c:1765 [inline] call_netdevice_notifiers net/core/dev.c:1779 [inline] __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:7628 dev_change_flags+0x10d/0x170 net/core/dev.c:7664 devinet_ioctl+0x138a/0x1c50 net/ipv4/devinet.c:1104 inet_ioctl+0x1f4/0x340 net/ipv4/af_inet.c:952 sock_do_ioctl+0xd8/0x2f0 net/socket.c:1049 sock_ioctl+0x3ed/0x780 net/socket.c:1200 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 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:00007f83d4642c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 0000000020000080 RSI: 0000000000008914 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f83d46436d4 R13: 00000000004c4c76 R14: 00000000004d89b8 R15: 00000000ffffffff Allocated by task 22004: 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+0x659/0x10f0 net/ipv6/route.c:1959 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2132 fib6_rule_lookup+0x133/0x5a0 net/ipv6/fib6_rules.c:116 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2161 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 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:293 sctp_transport_route+0x12d/0x360 net/sctp/transport.c:312 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:678 sctp_process_param net/sctp/sm_make_chunk.c:2546 [inline] sctp_process_init+0x2491/0x2b10 net/sctp/sm_make_chunk.c:2359 sctp_sf_do_unexpected_init net/sctp/sm_statefuns.c:1556 [inline] sctp_sf_do_unexpected_init.isra.0+0x7cd/0x1350 net/sctp/sm_statefuns.c:1456 sctp_sf_do_5_2_1_siminit+0x35/0x40 net/sctp/sm_statefuns.c:1685 sctp_do_sm+0x121/0x50e0 net/sctp/sm_sideeffect.c:1162 sctp_assoc_bh_rcv+0x343/0x660 net/sctp/associola.c:1074 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:95 sctp_backlog_rcv+0x196/0xbe0 net/sctp/input.c:354 sk_backlog_rcv include/net/sock.h:950 [inline] __release_sock+0x129/0x390 net/core/sock.c:2418 release_sock+0x59/0x1c0 net/core/sock.c:2934 sctp_wait_for_connect+0x316/0x540 net/sctp/socket.c:9054 __sctp_connect+0xab2/0xcd0 net/sctp/socket.c:1241 sctp_connect net/sctp/socket.c:4861 [inline] sctp_inet_connect+0x29c/0x340 net/sctp/socket.c:4877 __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 16: 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 ffff88809bde2300 which belongs to the cache ip6_dst_cache of size 224 The buggy address is located 6 bytes to the right of 224-byte region [ffff88809bde2300, ffff88809bde23e0) The buggy address belongs to the page: page:ffffea00026f7880 refcount:1 mapcount:0 mapping:ffff8880a3c26040 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002737d48 ffffea0001862e48 ffff8880a3c26040 raw: 0000000000000000 ffff88809bde2080 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809bde2280: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ffff88809bde2300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809bde2380: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ^ ffff88809bde2400: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88809bde2480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================