================================================================== BUG: KASAN: use-after-free in nf_hook_entries_get_hook_ops include/linux/netfilter.h:107 [inline] BUG: KASAN: use-after-free in hooks_validate+0x139/0x160 net/netfilter/core.c:170 Read of size 2 at addr ffff8880b2835680 by task syz-executor.0/6767 CPU: 1 PID: 6767 Comm: syz-executor.0 Not tainted 4.19.190-syzkaller #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+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load2_noabort+0x88/0x90 mm/kasan/report.c:431 nf_hook_entries_get_hook_ops include/linux/netfilter.h:107 [inline] hooks_validate+0x139/0x160 net/netfilter/core.c:170 __nf_register_net_hook+0x1b0/0x480 net/netfilter/core.c:345 nf_register_net_hook net/netfilter/core.c:463 [inline] nf_register_net_hooks+0x4c/0x190 net/netfilter/core.c:479 synproxy_tg6_check+0x3c1/0x610 net/ipv6/netfilter/ip6t_SYNPROXY.c:478 xt_check_target+0x26c/0x650 net/netfilter/x_tables.c:1023 check_target net/ipv6/netfilter/ip6_tables.c:532 [inline] find_check_entry.constprop.0+0x7f1/0x9e0 net/ipv6/netfilter/ip6_tables.c:575 translate_table+0xc46/0x16a0 net/ipv6/netfilter/ip6_tables.c:737 do_replace net/ipv6/netfilter/ip6_tables.c:1156 [inline] do_ip6t_set_ctl+0x29d/0x430 net/ipv6/netfilter/ip6_tables.c:1686 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x6f/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x103/0x160 net/ipv6/ipv6_sockglue.c:945 rawv6_setsockopt+0x55/0x140 net/ipv6/raw.c:1084 __sys_setsockopt+0x14d/0x240 net/socket.c:1901 __do_sys_setsockopt net/socket.c:1912 [inline] __se_sys_setsockopt net/socket.c:1909 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:1909 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f67a0578188 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000004 RBP: 00000000004bfce1 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000020000440 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffdf38c49ff R14: 00007f67a0578300 R15: 0000000000022000 Allocated by task 6767: __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x4c/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:557 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:423 kvmalloc include/linux/mm.h:577 [inline] kvzalloc include/linux/mm.h:585 [inline] allocate_hook_entries_size net/netfilter/core.c:60 [inline] nf_hook_entries_grow+0x140/0x780 net/netfilter/core.c:127 __nf_register_net_hook+0x15a/0x480 net/netfilter/core.c:336 nf_register_net_hook net/netfilter/core.c:463 [inline] nf_register_net_hooks+0x4c/0x190 net/netfilter/core.c:479 synproxy_tg6_check+0x3c1/0x610 net/ipv6/netfilter/ip6t_SYNPROXY.c:478 xt_check_target+0x26c/0x650 net/netfilter/x_tables.c:1023 check_target net/ipv6/netfilter/ip6_tables.c:532 [inline] find_check_entry.constprop.0+0x7f1/0x9e0 net/ipv6/netfilter/ip6_tables.c:575 translate_table+0xc46/0x16a0 net/ipv6/netfilter/ip6_tables.c:737 do_replace net/ipv6/netfilter/ip6_tables.c:1156 [inline] do_ip6t_set_ctl+0x29d/0x430 net/ipv6/netfilter/ip6_tables.c:1686 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x6f/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x103/0x160 net/ipv6/ipv6_sockglue.c:945 rawv6_setsockopt+0x55/0x140 net/ipv6/raw.c:1084 __sys_setsockopt+0x14d/0x240 net/socket.c:1901 __do_sys_setsockopt net/socket.c:1912 [inline] __se_sys_setsockopt net/socket.c:1909 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:1909 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 15131: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 kvfree+0x59/0x60 mm/util.c:452 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2584 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0x8ff/0x18b0 kernel/rcu/tree.c:2881 __do_softirq+0x265/0x980 kernel/softirq.c:292 The buggy address belongs to the object at ffff8880b2835680 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 0 bytes inside of 1024-byte region [ffff8880b2835680, ffff8880b2835a80) The buggy address belongs to the page: page:ffffea0002ca0d00 count:1 mapcount:0 mapping:ffff88813bff0ac0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0000e31788 ffffea00027a8588 ffff88813bff0ac0 raw: 0000000000000000 ffff8880b2834000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b2835580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880b2835600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880b2835680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880b2835700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880b2835780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================