ip_tables: iptables: counters copy to user failed while replacing table ================================================================== BUG: KASAN: use-after-free in l2tp_session_create+0xb1f/0xcc0 net/l2tp/l2tp_core.c:1809 Read of size 4 at addr ffff8880aa36d128 by task syz-executor.2/9997 CPU: 0 PID: 9997 Comm: syz-executor.2 Not tainted 4.14.298-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load4_noabort+0x68/0x70 mm/kasan/report.c:429 l2tp_session_create+0xb1f/0xcc0 net/l2tp/l2tp_core.c:1809 pppol2tp_connect+0xd40/0x13d0 net/l2tp/l2tp_ppp.c:773 SYSC_connect net/socket.c:1655 [inline] SyS_connect+0x1f4/0x240 net/socket.c:1636 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 Allocated by task 9997: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] l2tp_tunnel_create+0x40b/0xd90 net/l2tp/l2tp_core.c:1618 pppol2tp_connect+0xe54/0x13d0 net/l2tp/l2tp_ppp.c:725 SYSC_connect net/socket.c:1655 [inline] SyS_connect+0x1f4/0x240 net/socket.c:1636 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 Freed by task 7997: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 __rcu_reclaim kernel/rcu/rcu.h:190 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x88b/0x1180 kernel/rcu/tree.c:2946 __do_softirq+0x24d/0x9ff kernel/softirq.c:288 The buggy address belongs to the object at ffff8880aa36d040 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 232 bytes inside of 512-byte region [ffff8880aa36d040, ffff8880aa36d240) The buggy address belongs to the page: page:ffffea0002a8db40 count:1 mapcount:0 mapping:ffff8880aa36d040 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880aa36d040 0000000000000000 0000000100000006 raw: ffffea0002a8bba0 ffffea0002ac63e0 ffff88813fe74940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880aa36d000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8880aa36d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880aa36d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880aa36d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880aa36d200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== syz-executor.2 (9950) used greatest stack depth: 25248 bytes left