================================================================== BUG: KASAN: use-after-free in __nf_ct_ext_exist include/net/netfilter/nf_conntrack_extend.h:53 [inline] BUG: KASAN: use-after-free in nf_ct_ext_exist include/net/netfilter/nf_conntrack_extend.h:58 [inline] BUG: KASAN: use-after-free in __nf_ct_ext_find include/net/netfilter/nf_conntrack_extend.h:63 [inline] BUG: KASAN: use-after-free in nf_ct_ecache_find include/net/netfilter/nf_conntrack_ecache.h:35 [inline] BUG: KASAN: use-after-free in nf_ct_deliver_cached_events+0x5c3/0x6d0 net/netfilter/nf_conntrack_ecache.c:205 Read of size 1 at addr ffff888092829604 by task syz-executor.5/8234 CPU: 0 PID: 8234 Comm: syz-executor.5 Not tainted 5.4.0-rc4-next-20191025 #0 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.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:129 __nf_ct_ext_exist include/net/netfilter/nf_conntrack_extend.h:53 [inline] nf_ct_ext_exist include/net/netfilter/nf_conntrack_extend.h:58 [inline] __nf_ct_ext_find include/net/netfilter/nf_conntrack_extend.h:63 [inline] nf_ct_ecache_find include/net/netfilter/nf_conntrack_ecache.h:35 [inline] nf_ct_deliver_cached_events+0x5c3/0x6d0 net/netfilter/nf_conntrack_ecache.c:205 nf_conntrack_confirm include/net/netfilter/nf_conntrack_core.h:65 [inline] nf_confirm+0x3d8/0x4d0 net/netfilter/nf_conntrack_proto.c:154 ipv6_confirm+0x1e4/0x3a0 net/netfilter/nf_conntrack_proto.c:384 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xbc/0x1e0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:262 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] ip6_input+0x209/0x3f0 net/ipv6/ip6_input.c:459 dst_input include/net/dst.h:442 [inline] ip6_sublist_rcv_finish+0x9b/0x2d0 net/ipv6/ip6_input.c:85 ip6_list_rcv_finish net/ipv6/ip6_input.c:120 [inline] ip6_sublist_rcv+0x513/0x930 net/ipv6/ip6_input.c:294 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:328 __netif_receive_skb_list_ptype net/core/dev.c:5274 [inline] __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5322 __netif_receive_skb_list net/core/dev.c:5374 [inline] netif_receive_skb_list_internal+0x7eb/0xe50 net/core/dev.c:5469 gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5892 gro_normal_list net/core/dev.c:5905 [inline] gro_normal_one+0x184/0x1d0 net/core/dev.c:5904 napi_frags_finish net/core/dev.c:6008 [inline] napi_gro_frags+0x915/0xd00 net/core/dev.c:6081 tun_get_user+0x2e8e/0x3f80 drivers/net/tun.c:1976 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1902 [inline] do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x184/0x610 fs/read_write.c:951 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1015 do_writev+0x15b/0x330 fs/read_write.c:1058 __do_sys_writev fs/read_write.c:1131 [inline] __se_sys_writev fs/read_write.c:1128 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1128 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459df1 Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 e4 b7 fb ff c3 48 83 ec 08 e8 fa 2c 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 43 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f3687c6fba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 000000000000003e RCX: 0000000000459df1 RDX: 0000000000000001 RSI: 00007f3687c6fc00 RDI: 00000000000000f0 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f3687c706d4 R13: 00000000004c9352 R14: 00000000004e0a60 R15: 00000000ffffffff Allocated by task 8234: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_krealloc+0x84/0xc0 mm/kasan/common.c:565 __do_krealloc mm/slab_common.c:1655 [inline] krealloc+0xa6/0xd0 mm/slab_common.c:1710 nf_ct_ext_add+0x2c7/0x630 net/netfilter/nf_conntrack_extend.c:74 nf_ct_ecache_ext_add include/net/netfilter/nf_conntrack_ecache.h:55 [inline] init_conntrack.isra.0+0x5ed/0x11a0 net/netfilter/nf_conntrack_core.c:1470 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1547 [inline] nf_conntrack_in+0xd94/0x1460 net/netfilter/nf_conntrack_core.c:1707 ipv6_conntrack_in+0x1e/0x30 net/netfilter/nf_conntrack_proto.c:194 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xbc/0x1e0 net/netfilter/core.c:512 nf_hook_slow_list+0x1d9/0x480 net/netfilter/core.c:550 NF_HOOK_LIST include/linux/netfilter.h:343 [inline] ip6_sublist_rcv+0x677/0x930 net/ipv6/ip6_input.c:292 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:328 __netif_receive_skb_list_ptype net/core/dev.c:5274 [inline] __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5322 __netif_receive_skb_list net/core/dev.c:5374 [inline] netif_receive_skb_list_internal+0x7eb/0xe50 net/core/dev.c:5469 gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5892 gro_normal_list net/core/dev.c:5905 [inline] gro_normal_one+0x184/0x1d0 net/core/dev.c:5904 napi_frags_finish net/core/dev.c:6008 [inline] napi_gro_frags+0x915/0xd00 net/core/dev.c:6081 tun_get_user+0x2e8e/0x3f80 drivers/net/tun.c:1976 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1902 [inline] do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x184/0x610 fs/read_write.c:951 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1015 do_writev+0x15b/0x330 fs/read_write.c:1058 __do_sys_writev fs/read_write.c:1131 [inline] __se_sys_writev fs/read_write.c:1128 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1128 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8234: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 nf_ct_ext_destroy+0x2ab/0x2e0 net/netfilter/nf_conntrack_extend.c:38 nf_conntrack_free+0x8f/0xe0 net/netfilter/nf_conntrack_core.c:1418 destroy_conntrack+0x1a2/0x270 net/netfilter/nf_conntrack_core.c:626 nf_conntrack_destroy+0xed/0x230 net/netfilter/core.c:600 nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:34 [inline] nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:31 [inline] nf_ct_resolve_clash net/netfilter/nf_conntrack_core.c:915 [inline] __nf_conntrack_confirm+0x21ca/0x2830 net/netfilter/nf_conntrack_core.c:1038 nf_conntrack_confirm include/net/netfilter/nf_conntrack_core.h:63 [inline] nf_confirm+0x3e7/0x4d0 net/netfilter/nf_conntrack_proto.c:154 ipv6_confirm+0x1e4/0x3a0 net/netfilter/nf_conntrack_proto.c:384 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xbc/0x1e0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:262 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] ip6_input+0x209/0x3f0 net/ipv6/ip6_input.c:459 dst_input include/net/dst.h:442 [inline] ip6_sublist_rcv_finish+0x9b/0x2d0 net/ipv6/ip6_input.c:85 ip6_list_rcv_finish net/ipv6/ip6_input.c:120 [inline] ip6_sublist_rcv+0x513/0x930 net/ipv6/ip6_input.c:294 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:328 __netif_receive_skb_list_ptype net/core/dev.c:5274 [inline] __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5322 __netif_receive_skb_list net/core/dev.c:5374 [inline] netif_receive_skb_list_internal+0x7eb/0xe50 net/core/dev.c:5469 gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5892 gro_normal_list net/core/dev.c:5905 [inline] gro_normal_one+0x184/0x1d0 net/core/dev.c:5904 napi_frags_finish net/core/dev.c:6008 [inline] napi_gro_frags+0x915/0xd00 net/core/dev.c:6081 tun_get_user+0x2e8e/0x3f80 drivers/net/tun.c:1976 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1902 [inline] do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x184/0x610 fs/read_write.c:951 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1015 do_writev+0x15b/0x330 fs/read_write.c:1058 __do_sys_writev fs/read_write.c:1131 [inline] __se_sys_writev fs/read_write.c:1128 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1128 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888092829600 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 4 bytes inside of 128-byte region [ffff888092829600, ffff888092829680) The buggy address belongs to the page: page:ffffea00024a0a40 refcount:1 mapcount:0 mapping:ffff8880aa400700 index:0xffff888092829300 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026c8ac8 ffffea00024e2688 ffff8880aa400700 raw: ffff888092829300 ffff888092829000 000000010000000a 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888092829500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092829580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888092829600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888092829680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888092829700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================