netlink: 16 bytes leftover after parsing attributes in process `syz-executor0'. ================================================================== BUG: KASAN: slab-out-of-bounds in __ptr_ring_produce include/linux/ptr_ring.h:110 [inline] BUG: KASAN: slab-out-of-bounds in ptr_ring_produce include/linux/ptr_ring.h:133 [inline] BUG: KASAN: slab-out-of-bounds in tun_net_xmit+0x197e/0x1be0 drivers/net/tun.c:1119 Read of size 8 at addr ffff88808de6c988 by task syz-executor2/6339 CPU: 1 PID: 6339 Comm: syz-executor2 Not tainted 4.20.0+ #363 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+0x1d3/0x2c6 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __ptr_ring_produce include/linux/ptr_ring.h:110 [inline] ptr_ring_produce include/linux/ptr_ring.h:133 [inline] tun_net_xmit+0x197e/0x1be0 drivers/net/tun.c:1119 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] xmit_one net/core/dev.c:3278 [inline] dev_hard_start_xmit+0x286/0xc80 net/core/dev.c:3294 sch_direct_xmit+0x48b/0x1130 net/sched/sch_generic.c:327 qdisc_restart net/sched/sch_generic.c:390 [inline] __qdisc_run+0x624/0x19f0 net/sched/sch_generic.c:398 qdisc_run include/net/pkt_sched.h:121 [inline] __dev_xmit_skb net/core/dev.c:3473 [inline] __dev_queue_xmit+0x190c/0x3ac0 net/core/dev.c:3832 dev_queue_xmit+0x17/0x20 net/core/dev.c:3897 neigh_hh_output include/net/neighbour.h:498 [inline] neigh_output include/net/neighbour.h:506 [inline] ip6_finish_output2+0x144e/0x2930 net/ipv6/ip6_output.c:120 ip6_finish_output+0x583/0xc50 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0xc5/0x1b0 net/ipv6/output_core.c:176 ip6_send_skb+0xbc/0x340 net/ipv6/ip6_output.c:1727 udp_v6_send_skb.isra.32+0x831/0x14a0 net/ipv6/udp.c:1169 udpv6_sendmsg+0x2d86/0x36a0 net/ipv6/udp.c:1466 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 __sys_sendto+0x3d7/0x670 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto net/socket.c:1796 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fde29b85c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000006 RBP: 000000000073c040 R08: 00000000200001c0 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 00007fde29b866d4 R13: 00000000004c525c R14: 00000000004d8a60 R15: 00000000ffffffff Allocated by task 6332: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node+0x50/0x70 mm/slab.c:3691 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x65/0xf0 mm/util.c:416 kvmalloc include/linux/mm.h:577 [inline] kvmalloc_array include/linux/mm.h:595 [inline] __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:475 [inline] ptr_ring_resize_multiple include/linux/ptr_ring.h:635 [inline] tun_queue_resize drivers/net/tun.c:3606 [inline] tun_device_event+0x56a/0x106c drivers/net/tun.c:3625 notifier_call_chain+0x17e/0x380 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline] call_netdevice_notifiers net/core/dev.c:1765 [inline] dev_change_tx_queue_len+0x188/0x270 net/core/dev.c:7742 dev_ifsioc+0x79b/0xa80 net/core/dev_ioctl.c:287 dev_ioctl+0x1b5/0xcc0 net/core/dev_ioctl.c:488 sock_do_ioctl+0x1f6/0x420 net/socket.c:973 sock_ioctl+0x313/0x690 net/socket.c:1074 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696 ksys_ioctl+0xa9/0xd0 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+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 25909: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 kvfree+0x61/0x70 mm/util.c:445 xt_free_table_info+0xbb/0x180 net/netfilter/x_tables.c:1197 __do_replace+0x855/0xab0 net/ipv4/netfilter/ip_tables.c:1090 do_replace net/ipv4/netfilter/ip_tables.c:1143 [inline] do_ipt_set_ctl+0x49c/0x645 net/ipv4/netfilter/ip_tables.c:1675 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x7d/0xd0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0xd8/0xf0 net/ipv4/ip_sockglue.c:1260 tcp_setsockopt+0x93/0xe0 net/ipv4/tcp.c:3068 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2986 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88808de6c980 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 8 bytes inside of 32-byte region [ffff88808de6c980, ffff88808de6c9a0) The buggy address belongs to the page: page:ffffea0002379b00 count:1 mapcount:0 mapping:ffff88812c3f01c0 index:0xffff88808de6cfc1 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00029fa988 ffffea000239c088 ffff88812c3f01c0 raw: ffff88808de6cfc1 ffff88808de6c000 0000000100000030 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808de6c880: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff88808de6c900: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff88808de6c980: 00 fc fc fc fc fc fc fc 00 00 00 fc fc fc fc fc ^ ffff88808de6ca00: 00 00 00 fc fc fc fc fc 00 00 00 fc fc fc fc fc ffff88808de6ca80: 07 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================