================================================================== BUG: KASAN: use-after-free in rt_cache_valid+0x158/0x190 net/ipv4/route.c:1557 Read of size 2 at addr ffff8880913b4d88 by task syz-executor.1/13477 CPU: 1 PID: 13477 Comm: syz-executor.1 Not tainted 5.2.0-rc3+ #20 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load2_noabort+0x14/0x20 mm/kasan/generic_report.c:130 rt_cache_valid+0x158/0x190 net/ipv4/route.c:1557 __mkroute_output net/ipv4/route.c:2333 [inline] ip_route_output_key_hash_rcu+0x819/0x2d50 net/ipv4/route.c:2565 ip_route_output_key_hash+0x1ef/0x360 net/ipv4/route.c:2394 __ip_route_output_key include/net/route.h:125 [inline] ip_route_connect include/net/route.h:303 [inline] tcp_v4_connect+0x7ec/0x1c40 net/ipv4/tcp_ipv4.c:228 __inet_stream_connect+0x834/0xe90 net/ipv4/af_inet.c:655 tcp_sendmsg_fastopen net/ipv4/tcp.c:1139 [inline] tcp_sendmsg_locked+0x2318/0x3920 net/ipv4/tcp.c:1181 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1415 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:665 __sys_sendto+0x262/0x380 net/socket.c:1958 __do_sys_sendto net/socket.c:1970 [inline] __se_sys_sendto net/socket.c:1966 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1966 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: fd 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fd8faeb3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000459279 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000075c060 R08: 0000000020e68000 R09: 0000000000000010 R10: 00000000200007fd R11: 0000000000000246 R12: 00007fd8faeb46d4 R13: 00000000004c700b R14: 00000000004dc1c8 R15: 00000000ffffffff Allocated by task 8433: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488 dst_alloc+0x10e/0x200 net/core/dst.c:93 rt_dst_alloc+0x83/0x3f0 net/ipv4/route.c:1625 ip_route_input_slow+0x17f6/0x3770 net/ipv4/route.c:2114 ip_route_input_rcu+0xdf/0xbc0 net/ipv4/route.c:2244 ip_route_input_noref+0x12f/0x270 net/ipv4/route.c:2189 ip_rcv_finish_core.isra.0+0x45e/0x1b60 net/ipv4/ip_input.c:338 ip_rcv_finish+0x143/0x2f0 net/ipv4/ip_input.c:411 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:4981 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5095 process_backlog+0x206/0x750 net/core/dev.c:5906 napi_poll net/core/dev.c:6329 [inline] net_rx_action+0x4f5/0x1070 net/core/dev.c:6395 __do_softirq+0x25c/0x94c kernel/softirq.c:293 Freed by task 16: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 dst_destroy+0x29e/0x3c0 net/core/dst.c:129 dst_destroy_rcu+0x16/0x19 net/core/dst.c:142 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c kernel/softirq.c:293 The buggy address belongs to the object at ffff8880913b4d00 which belongs to the cache ip_dst_cache of size 176 The buggy address is located 136 bytes inside of 176-byte region [ffff8880913b4d00, ffff8880913b4db0) The buggy address belongs to the page: page:ffffea000244ed00 refcount:1 mapcount:0 mapping:ffff88821adb1d80 index:0xffff8880913b4f00 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0001b90388 ffffea000242a288 ffff88821adb1d80 raw: ffff8880913b4f00 ffff8880913b4000 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880913b4c80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff8880913b4d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880913b4d80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff8880913b4e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880913b4e80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ==================================================================