ip_tunnel: non-ECT from 172.40.20.187 with TOS=0x3 IPv4: Oversized IP packet from 127.0.0.1 ip_tunnel: non-ECT from 172.40.20.187 with TOS=0x3 ================================================================== BUG: KASAN: use-after-free in qdisc_pkt_len_init net/core/dev.c:3085 [inline] BUG: KASAN: use-after-free in __dev_queue_xmit+0x18fc/0x2080 net/core/dev.c:3395 Read of size 2 at addr ffff8801da0fcfc2 by task syz-executor5/5916 CPU: 0 PID: 5916 Comm: syz-executor5 Not tainted 4.9.100-g73fdfa3 #26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801b7977720 ffffffff81eb0f09 ffffea0007683f00 ffff8801da0fcfc2 0000000000000000 ffff8801da0fcfc2 ffff8801da0d6990 ffff8801b7977758 ffffffff8156532b ffff8801da0fcfc2 0000000000000002 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x6c/0x234 mm/kasan/report.c:256 [] kasan_report_error mm/kasan/report.c:355 [inline] [] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412 [] __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431 [] qdisc_pkt_len_init net/core/dev.c:3085 [inline] [] __dev_queue_xmit+0x18fc/0x2080 net/core/dev.c:3395 [] dev_queue_xmit+0x17/0x20 net/core/dev.c:3484 [] packet_snd net/packet/af_packet.c:2960 [inline] [] packet_sendmsg+0x1eff/0x4470 net/packet/af_packet.c:2985 [] sock_sendmsg_nosec net/socket.c:635 [inline] [] sock_sendmsg+0xcc/0x110 net/socket.c:645 [] SYSC_sendto+0x21c/0x370 net/socket.c:1670 [] SyS_sendto+0x40/0x50 net/socket.c:1638 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Allocated by task 5916: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:609 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547 slab_post_alloc_hook mm/slab.h:417 [inline] slab_alloc_node mm/slub.c:2715 [inline] slab_alloc mm/slub.c:2723 [inline] __kmalloc_track_caller+0xdc/0x2b0 mm/slub.c:4232 __kmalloc_reserve.isra.37+0x33/0xc0 net/core/skbuff.c:138 __alloc_skb+0x11a/0x600 net/core/skbuff.c:231 alloc_skb include/linux/skbuff.h:919 [inline] alloc_skb_with_frags+0xaf/0x520 net/core/skbuff.c:4679 sock_alloc_send_pskb+0x5a9/0x750 net/core/sock.c:1893 packet_alloc_skb net/packet/af_packet.c:2817 [inline] packet_snd net/packet/af_packet.c:2908 [inline] packet_sendmsg+0x1581/0x4470 net/packet/af_packet.c:2985 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xcc/0x110 net/socket.c:645 SYSC_sendto+0x21c/0x370 net/socket.c:1670 SyS_sendto+0x40/0x50 net/socket.c:1638 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb Freed by task 5916: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:582 slab_free_hook mm/slub.c:1355 [inline] slab_free_freelist_hook mm/slub.c:1377 [inline] slab_free mm/slub.c:2958 [inline] kfree+0xfb/0x310 mm/slub.c:3878 skb_free_head+0x8b/0xb0 net/core/skbuff.c:580 skb_release_data+0x329/0x400 net/core/skbuff.c:611 skb_release_all+0x4a/0x60 net/core/skbuff.c:670 __kfree_skb+0x15/0x20 net/core/skbuff.c:684 kfree_skb+0xcc/0x340 net/core/skbuff.c:705 __skb_complete_tx_timestamp+0x2ba/0x3a0 net/core/skbuff.c:3824 __skb_tstamp_tx+0x19a/0x4b0 net/core/skbuff.c:3896 __dev_queue_xmit+0x130f/0x2080 net/core/dev.c:3386 dev_queue_xmit+0x17/0x20 net/core/dev.c:3484 packet_snd net/packet/af_packet.c:2960 [inline] packet_sendmsg+0x1eff/0x4470 net/packet/af_packet.c:2985 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xcc/0x110 net/socket.c:645 SYSC_sendto+0x21c/0x370 net/socket.c:1670 SyS_sendto+0x40/0x50 net/socket.c:1638 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb The buggy address belongs to the object at ffff8801da0fcf00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 194 bytes inside of 512-byte region [ffff8801da0fcf00, ffff8801da0fd100) The buggy address belongs to the page: page:ffffea0007683f00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x8000000000004080(slab|head) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801da0fce80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801da0fcf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801da0fcf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801da0fd000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801da0fd080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================