================================================================== BUG: KASAN: slab-out-of-bounds in fib6_nh_get_excptn_bucket+0x198/0x1b0 net/ipv6/route.c:1595 Read of size 8 at addr ffff8880a9608df8 by task syz-executor.3/26948 CPU: 1 PID: 26948 Comm: syz-executor.3 Not tainted 5.5.0-rc1-next-20191213-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+0x197/0x210 lib/dump_stack.c:118 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:639 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135 fib6_nh_get_excptn_bucket+0x198/0x1b0 net/ipv6/route.c:1595 fib6_nh_flush_exceptions+0x37/0x2d0 net/ipv6/route.c:1723 fib6_nh_release+0x84/0x3a0 net/ipv6/route.c:3505 fib6_info_destroy_rcu+0x197/0x220 net/ipv6/ip6_fib.c:174 rcu_do_batch kernel/rcu/tree.c:2204 [inline] rcu_core+0x5e3/0x1440 kernel/rcu/tree.c:2431 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2440 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:180 Code: ff cc cc cc cc cc cc cc cc cc 65 48 8b 04 25 c0 1e 02 00 48 8b 80 a0 13 00 00 c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 65 48 8b 04 25 c0 1e 02 00 65 8b 15 44 dd 8c 7e 81 e2 RSP: 0018:ffffc900072a7738 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: 00007f0543c67000 RCX: ffffffff81a2a07f RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc900072a7898 R08: ffff888066346540 R09: fffff94000325217 R10: fffff94000325216 R11: ffffea00019290b3 R12: 0000000000000000 R13: ffff88808c35e330 R14: dffffc0000000000 R15: ffffea0001929080 unmap_single_vma+0x19d/0x300 mm/memory.c:1300 unmap_vmas+0x184/0x2f0 mm/memory.c:1332 exit_mmap+0x2ba/0x530 mm/mmap.c:3155 __mmput kernel/fork.c:1082 [inline] mmput+0x179/0x4d0 kernel/fork.c:1103 exit_mm kernel/exit.c:485 [inline] do_exit+0x828/0x2f20 kernel/exit.c:784 do_group_exit+0x135/0x360 kernel/exit.c:895 get_signal+0x47c/0x24f0 kernel/signal.c:2734 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a909 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f054243fcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 000000000075bf28 RCX: 000000000045a909 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bf28 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bf2c R13: 00007ffc3a36839f R14: 00007f05424409c0 R15: 000000000075bf2c Allocated by task 26948: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:670 [inline] fib6_info_alloc+0xb6/0x1b0 net/ipv6/ip6_fib.c:154 ip6_route_info_create+0x2ff/0x1500 net/ipv6/route.c:3607 ip6_route_add+0x27/0x110 net/ipv6/route.c:3699 inet6_rtm_newroute+0x16c/0x180 net/ipv6/route.c:5267 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5424 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x753/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg net/socket.c:2424 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26209: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 call_usermodehelper_freeinfo kernel/umh.c:48 [inline] call_usermodehelper_exec+0x25a/0x500 kernel/umh.c:598 call_modprobe kernel/kmod.c:99 [inline] __request_module+0x478/0xbb6 kernel/kmod.c:171 crypto_larval_lookup crypto/api.c:228 [inline] crypto_alg_mod_lookup+0x263/0x5b0 crypto/api.c:275 crypto_has_alg+0x27/0x160 crypto/api.c:572 crypto_has_comp include/linux/crypto.h:910 [inline] xfrm_probe_algs net/xfrm/xfrm_algo.c:795 [inline] xfrm_probe_algs+0x1fb/0x2e0 net/xfrm/xfrm_algo.c:776 pfkey_register+0xe5/0xd30 net/key/af_key.c:1704 pfkey_process+0x6cf/0x810 net/key/af_key.c:2834 pfkey_sendmsg+0x41f/0xc10 net/key/af_key.c:3673 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x358/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2474 __do_sys_sendmmsg net/socket.c:2503 [inline] __se_sys_sendmmsg net/socket.c:2500 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2500 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a9608d00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 56 bytes to the right of 192-byte region [ffff8880a9608d00, ffff8880a9608dc0) The buggy address belongs to the page: page:ffffea0002a58200 refcount:1 mapcount:0 mapping:ffff8880aa400000 index:0xffff8880a9608700 raw: 00fffe0000000200 ffffea0002884d88 ffffea0002a5f008 ffff8880aa400000 raw: ffff8880a9608700 ffff8880a9608000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a9608c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a9608d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a9608d80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a9608e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a9608e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================