================================================================== BUG: KASAN: use-after-free in memcpy include/linux/string.h:344 [inline] BUG: KASAN: use-after-free in array_map_update_elem+0x197/0x240 kernel/bpf/arraymap.c:249 Write of size 1 at addr ffff8801c516a280 by task syz-executor5/18997 CPU: 0 PID: 18997 Comm: syz-executor5 Not tainted 4.15.0-rc7+ #186 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:344 [inline] array_map_update_elem+0x197/0x240 kernel/bpf/arraymap.c:249 map_update_elem kernel/bpf/syscall.c:687 [inline] SYSC_bpf kernel/bpf/syscall.c:1811 [inline] SyS_bpf+0x32df/0x4400 kernel/bpf/syscall.c:1782 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x452ac9 RSP: 002b:00007f052bbc3c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9 RDX: 0000000000000020 RSI: 0000000020eaf000 RDI: 0000000000000002 RBP: 00000000000003aa R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3890 R13: 00000000ffffffff R14: 000000000071bf18 R15: 0000000000000000 Allocated by task 3492: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc_node+0x144/0x760 mm/slab.c:3634 __alloc_skb+0xf1/0x780 net/core/skbuff.c:193 alloc_skb_fclone include/linux/skbuff.h:1025 [inline] sk_stream_alloc_skb+0x11d/0x900 net/ipv4/tcp.c:866 tso_fragment net/ipv4/tcp_output.c:1880 [inline] tcp_write_xmit+0x21b8/0x52a0 net/ipv4/tcp_output.c:2359 __tcp_push_pending_frames+0xa0/0x250 net/ipv4/tcp_output.c:2541 tcp_push+0x53e/0x770 net/ipv4/tcp.c:726 tcp_sendmsg_locked+0x289a/0x3c70 net/ipv4/tcp.c:1426 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1463 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 sock_write_iter+0x31a/0x5d0 net/socket.c:909 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 entry_SYSCALL_64_fastpath+0x23/0x9a Freed by task 3492: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3488 [inline] kmem_cache_free+0x83/0x2a0 mm/slab.c:3746 kfree_skbmem+0xdd/0x1d0 net/core/skbuff.c:603 __kfree_skb net/core/skbuff.c:642 [inline] consume_skb+0x15b/0x490 net/core/skbuff.c:701 __dev_kfree_skb_any+0x85/0xa0 net/core/dev.c:2544 dev_consume_skb_any include/linux/netdevice.h:3279 [inline] free_old_xmit_skbs.isra.27+0x160/0x2c0 drivers/net/virtio_net.c:1176 start_xmit+0x1b9/0x16f0 drivers/net/virtio_net.c:1328 __netdev_start_xmit include/linux/netdevice.h:4046 [inline] netdev_start_xmit include/linux/netdevice.h:4055 [inline] xmit_one net/core/dev.c:3020 [inline] dev_hard_start_xmit+0x24e/0xac0 net/core/dev.c:3036 sch_direct_xmit+0x40d/0x1140 net/sched/sch_generic.c:327 qdisc_restart net/sched/sch_generic.c:393 [inline] __qdisc_run+0x57d/0x19c0 net/sched/sch_generic.c:401 __dev_xmit_skb net/core/dev.c:3200 [inline] __dev_queue_xmit+0xb62/0x2b50 net/core/dev.c:3501 dev_queue_xmit+0x17/0x20 net/core/dev.c:3566 neigh_hh_output include/net/neighbour.h:472 [inline] neigh_output include/net/neighbour.h:480 [inline] ip_finish_output2+0xef9/0x14f0 net/ipv4/ip_output.c:229 ip_finish_output+0x864/0xd10 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip_output+0x1d2/0x860 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:443 [inline] ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124 ip_queue_xmit+0x8c0/0x18e0 net/ipv4/ip_output.c:504 tcp_transmit_skb+0x1b1b/0x38c0 net/ipv4/tcp_output.c:1176 tcp_write_xmit+0x68e/0x52a0 net/ipv4/tcp_output.c:2368 __tcp_push_pending_frames+0xa0/0x250 net/ipv4/tcp_output.c:2541 tcp_push+0x53e/0x770 net/ipv4/tcp.c:726 tcp_sendmsg_locked+0x289a/0x3c70 net/ipv4/tcp.c:1426 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1463 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 sock_write_iter+0x31a/0x5d0 net/socket.c:909 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 entry_SYSCALL_64_fastpath+0x23/0x9a The buggy address belongs to the object at ffff8801c516a280 which belongs to the cache skbuff_fclone_cache of size 472 The buggy address is located 0 bytes inside of 472-byte region [ffff8801c516a280, ffff8801c516a458) The buggy address belongs to the page: page:ffffea0007145a80 count:1 mapcount:0 mapping:ffff8801c516a000 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c516a000 0000000000000000 0000000100000006 raw: ffffea0007120360 ffffea00070f4be0 ffff8801d9842500 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c516a180: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff8801c516a200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801c516a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c516a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c516a380: 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