netlink: 13 bytes leftover after parsing attributes in process `syz-executor5'. ================================================================== BUG: KASAN: use-after-free in rtnetlink_put_metrics+0x621/0x690 net/core/rtnetlink.c:754 Read of size 4 at addr ffff8801d87ddd80 by task blkid/24428 CPU: 1 PID: 24428 Comm: blkid Not tainted 4.18.0-rc7+ #36 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 IPVS: length: 73 != 8 rtnetlink_put_metrics+0x621/0x690 net/core/rtnetlink.c:754 rt6_fill_node+0x7d9/0x1540 net/ipv6/route.c:4753 inet6_rt_notify+0x161/0x2c0 net/ipv6/route.c:4985 fib6_del_route net/ipv6/ip6_fib.c:1788 [inline] fib6_del+0xf4d/0x1310 net/ipv6/ip6_fib.c:1815 fib6_clean_node+0x3ee/0x5e0 net/ipv6/ip6_fib.c:1976 fib6_walk_continue+0x4b1/0x8e0 net/ipv6/ip6_fib.c:1899 fib6_walk+0x95/0xf0 net/ipv6/ip6_fib.c:1947 fib6_clean_tree+0x1ea/0x360 net/ipv6/ip6_fib.c:2024 __fib6_clean_all+0x21c/0x420 net/ipv6/ip6_fib.c:2040 fib6_clean_all net/ipv6/ip6_fib.c:2051 [inline] fib6_run_gc+0x182/0x3d0 net/ipv6/ip6_fib.c:2107 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2124 call_timer_fn+0x242/0x970 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7a6/0xc70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e8/0xb17 kernel/softirq.c:292 netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x1d4/0x210 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:527 [inline] smp_apic_timer_interrupt+0x186/0x730 arch/x86/kernel/apic/apic.c:1055 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:783 [inline] RIP: 0010:lock_release+0x4dc/0xa30 kernel/locking/lockdep.c:3946 Code: 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 cd 03 00 00 48 83 3d 5b 92 92 06 00 0f 84 c4 02 00 00 48 8b bd e8 fe ff ff 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. RSP: 0000:ffff880198b36fd0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 1ffff10033166dff RCX: 1ffff1003220a18d RDX: 1ffffffff0fe3615 RSI: 0000000000000004 RDI: 0000000000000286 RBP: ffff880198b37100 R08: 1ffff10033166e03 R09: ffffed003b6246d6 R10: 0000000000000003 R11: 0000000000000003 R12: ffff880191050440 R13: ffffffff87f926a0 R14: ffff880191050440 R15: ffff880198b37018 rcu_lock_release include/linux/rcupdate.h:250 [inline] rcu_read_unlock include/linux/rcupdate.h:685 [inline] __unlock_page_memcg+0x72/0x100 mm/memcontrol.c:1654 unlock_page_memcg+0x2c/0x40 mm/memcontrol.c:1663 page_add_file_rmap+0x781/0xe40 mm/rmap.c:1207 alloc_set_pte+0x932/0x1620 mm/memory.c:3456 filemap_map_pages+0x11ff/0x18b0 mm/filemap.c:2677 do_fault_around mm/memory.c:3602 [inline] do_read_fault mm/memory.c:3636 [inline] do_fault mm/memory.c:3741 [inline] handle_pte_fault mm/memory.c:3972 [inline] __handle_mm_fault+0x3384/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x7f9d47f97900 Code: ff 48 8d 3a 48 81 ec 80 00 00 00 e8 8a d4 03 00 48 81 c4 80 00 00 00 e9 73 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 3f 00 00 00 0f 05 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d 01 95 2d RSP: 002b:00007ffd850432b8 EFLAGS: 00010206 RAX: 00000000ffffffff RBX: 0000000000000003 RCX: 0000000000002000 RDX: 0000000000006000 RSI: 00000000024a7040 RDI: 00007ffd850432d0 RBP: 00000000024a7040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007f9d47f97900 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005 Allocated by task 20765: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] fib6_metric_set+0x163/0x2c0 net/ipv6/ip6_fib.c:645 fib6_add_rt2node+0xe36/0x27f0 net/ipv6/ip6_fib.c:1000 fib6_add+0xaae/0x14d0 net/ipv6/ip6_fib.c:1308 __ip6_ins_rt+0x54/0x80 net/ipv6/route.c:1163 ip6_route_add+0x6d/0xc0 net/ipv6/route.c:3171 addrconf_prefix_route.isra.48+0x51d/0x720 net/ipv6/addrconf.c:2347 inet6_addr_modify net/ipv6/addrconf.c:4627 [inline] inet6_rtm_newaddr+0x112e/0x1b50 net/ipv6/addrconf.c:4743 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4665 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2453 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4683 netlink_unicast_kernel net/netlink/af_netlink.c:1315 [inline] netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1341 netlink_sendmsg+0xa18/0xfd0 net/netlink/af_netlink.c:1906 sock_sendmsg_nosec net/socket.c:642 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:652 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126 __sys_sendmsg+0x11d/0x290 net/socket.c:2164 __do_sys_sendmsg net/socket.c:2173 [inline] __se_sys_sendmsg net/socket.c:2171 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 24428: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 fib6_metrics_release+0x77/0x90 net/ipv6/ip6_fib.c:179 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:899 [inline] fib6_purge_rt+0x5ec/0x7f0 net/ipv6/ip6_fib.c:934 fib6_del_route net/ipv6/ip6_fib.c:1784 [inline] fib6_del+0xc11/0x1310 net/ipv6/ip6_fib.c:1815 fib6_clean_node+0x3ee/0x5e0 net/ipv6/ip6_fib.c:1976 fib6_walk_continue+0x4b1/0x8e0 net/ipv6/ip6_fib.c:1899 fib6_walk+0x95/0xf0 net/ipv6/ip6_fib.c:1947 fib6_clean_tree+0x1ea/0x360 net/ipv6/ip6_fib.c:2024 __fib6_clean_all+0x21c/0x420 net/ipv6/ip6_fib.c:2040 fib6_clean_all net/ipv6/ip6_fib.c:2051 [inline] fib6_run_gc+0x182/0x3d0 net/ipv6/ip6_fib.c:2107 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2124 call_timer_fn+0x242/0x970 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7a6/0xc70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e8/0xb17 kernel/softirq.c:292 The buggy address belongs to the object at ffff8801d87ddd80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff8801d87ddd80, ffff8801d87ddde0) The buggy address belongs to the page: page:ffffea000761f740 count:1 mapcount:0 mapping:ffff8801dac004c0 index:0xffff8801d87ddc00 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0006a18808 ffffea00071df108 ffff8801dac004c0 raw: ffff8801d87ddc00 ffff8801d87dd000 0000000100000017 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d87ddc80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8801d87ddd00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff8801d87ddd80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8801d87dde00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8801d87dde80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ==================================================================