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BUG: KASAN: use-after-free in dump_schedule+0x758/0x7d0 net/sched/sch_taprio.c:1764
Read of size 8 at addr ffff88808966a8c0 by task syz-executor838/27630

CPU: 0 PID: 27630 Comm: syz-executor838 Not tainted 5.9.0-rc3-next-20200903-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+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 dump_schedule+0x758/0x7d0 net/sched/sch_taprio.c:1764
 taprio_dump+0x55d/0xce0 net/sched/sch_taprio.c:1833
 tc_fill_qdisc+0x5e7/0x1220 net/sched/sch_api.c:916
 qdisc_notify.isra.0+0x2b1/0x310 net/sched/sch_api.c:983
 tc_modify_qdisc+0xf45/0x1990 net/sched/sch_api.c:1635
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 sock_no_sendpage+0xee/0x130 net/core/sock.c:2838
 kernel_sendpage net/socket.c:3644 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:944
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0xbcd/0x1820 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice fs/splice.c:1401 [inline]
 __x64_sys_splice+0x198/0x250 fs/splice.c:1401
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x443f49
Code: e8 2c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd1856a778 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000443f49
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000000ad695 R08: 0000000000010973 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000404d70 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 27611:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 kmem_cache_alloc_trace+0x174/0x2c0 mm/slab.c:3550
 kmalloc include/linux/slab.h:554 [inline]
 kzalloc include/linux/slab.h:666 [inline]
 taprio_change+0x59f/0x2b50 net/sched/sch_taprio.c:1454
 qdisc_change net/sched/sch_api.c:1331 [inline]
 tc_modify_qdisc+0xd41/0x1990 net/sched/sch_api.c:1633
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 sock_no_sendpage+0xee/0x130 net/core/sock.c:2838
 kernel_sendpage net/socket.c:3644 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:944
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0xbcd/0x1820 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice fs/splice.c:1401 [inline]
 __x64_sys_splice+0x198/0x250 fs/splice.c:1401
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 16:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3418 [inline]
 kfree+0x10e/0x2b0 mm/slab.c:3756
 taprio_free_sched_cb+0x18b/0x240 net/sched/sch_taprio.c:124
 rcu_do_batch kernel/rcu/tree.c:2474 [inline]
 rcu_core+0x621/0x11d0 kernel/rcu/tree.c:2709
 __do_softirq+0x1f7/0xa91 kernel/softirq.c:298

Last call_rcu():
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346
 __call_rcu kernel/rcu/tree.c:2951 [inline]
 call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:3025
 taprio_change+0x2102/0x2b50 net/sched/sch_taprio.c:1572
 qdisc_change net/sched/sch_api.c:1331 [inline]
 tc_modify_qdisc+0xd41/0x1990 net/sched/sch_api.c:1633
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 sock_no_sendpage+0xee/0x130 net/core/sock.c:2838
 kernel_sendpage net/socket.c:3644 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:944
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0xbcd/0x1820 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice fs/splice.c:1401 [inline]
 __x64_sys_splice+0x198/0x250 fs/splice.c:1401
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Second to last call_rcu():
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346
 __call_rcu kernel/rcu/tree.c:2951 [inline]
 call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:3025
 taprio_change+0x2102/0x2b50 net/sched/sch_taprio.c:1572
 qdisc_change net/sched/sch_api.c:1331 [inline]
 tc_modify_qdisc+0xd41/0x1990 net/sched/sch_api.c:1633
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 sock_no_sendpage+0xee/0x130 net/core/sock.c:2838
 kernel_sendpage net/socket.c:3644 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:944
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0xbcd/0x1820 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice fs/splice.c:1401 [inline]
 __x64_sys_splice+0x198/0x250 fs/splice.c:1401
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88808966a880
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 64 bytes inside of
 96-byte region [ffff88808966a880, ffff88808966a8e0)
The buggy address belongs to the page:
page:0000000030d3a9d6 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88808966a680 pfn:0x8966a
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00022ba288 ffffea000250f5c8 ffff8880aa040300
raw: ffff88808966a680 ffff88808966a000 0000000100000012 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808966a780: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff88808966a800: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff88808966a880: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                           ^
 ffff88808966a900: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88808966a980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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