================================================================== BUG: KASAN: use-after-free in dump_schedule+0x758/0x7d0 net/sched/sch_taprio.c:1786 Read of size 8 at addr ffff8880191762c0 by task syz-executor.3/16407 CPU: 1 PID: 16407 Comm: syz-executor.3 Not tainted 5.10.0-next-20201223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230 __kasan_report mm/kasan/report.c:396 [inline] kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413 dump_schedule+0x758/0x7d0 net/sched/sch_taprio.c:1786 taprio_dump+0x5f1/0xe20 net/sched/sch_taprio.c:1855 tc_fill_qdisc+0x611/0x12f0 net/sched/sch_api.c:916 qdisc_notify.isra.0+0x2b1/0x310 net/sched/sch_api.c:983 tc_modify_qdisc+0xf6f/0x1a30 net/sched/sch_api.c:1635 rtnetlink_rcv_msg+0x498/0xb80 net/core/rtnetlink.c:5564 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x907/0xe40 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_no_sendpage+0xee/0x130 net/core/sock.c:2846 kernel_sendpage.part.0+0x1cb/0x380 net/socket.c:3636 kernel_sendpage net/socket.c:3633 [inline] sock_sendpage+0xe5/0x140 net/socket.c:945 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x45e/0x8c0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] do_splice+0xb7b/0x1aa0 fs/splice.c:1059 __do_splice+0x134/0x250 fs/splice.c:1137 __do_sys_splice fs/splice.c:1343 [inline] __se_sys_splice fs/splice.c:1325 [inline] __x64_sys_splice+0x198/0x250 fs/splice.c:1325 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e149 Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fbb7e16fc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e149 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000119bfd8 R08: 0000000000010973 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffe9b63d6cf R14: 00007fbb7e1709c0 R15: 000000000119bf8c Allocated by task 16401: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:404 [inline] ____kasan_kmalloc mm/kasan/common.c:435 [inline] ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:407 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:682 [inline] taprio_change+0x5d7/0x2e90 net/sched/sch_taprio.c:1461 taprio_init+0x52e/0x670 net/sched/sch_taprio.c:1709 qdisc_create+0x4ba/0x13a0 net/sched/sch_api.c:1246 tc_modify_qdisc+0x4c8/0x1a30 net/sched/sch_api.c:1662 rtnetlink_rcv_msg+0x498/0xb80 net/core/rtnetlink.c:5564 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x907/0xe40 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_no_sendpage+0xee/0x130 net/core/sock.c:2846 kernel_sendpage.part.0+0x1cb/0x380 net/socket.c:3636 kernel_sendpage net/socket.c:3633 [inline] sock_sendpage+0xe5/0x140 net/socket.c:945 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x45e/0x8c0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] do_splice+0xb7b/0x1aa0 fs/splice.c:1059 __do_splice+0x134/0x250 fs/splice.c:1137 __do_sys_splice fs/splice.c:1343 [inline] __se_sys_splice fs/splice.c:1325 [inline] __x64_sys_splice+0x198/0x250 fs/splice.c:1325 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 11392: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:355 ____kasan_slab_free.part.0+0xe1/0x110 mm/kasan/common.c:365 kasan_slab_free include/linux/kasan.h:188 [inline] slab_free_hook mm/slub.c:1548 [inline] slab_free_freelist_hook+0x82/0x1d0 mm/slub.c:1586 slab_free mm/slub.c:3157 [inline] kfree+0xdb/0x3c0 mm/slub.c:4156 taprio_free_sched_cb+0x18b/0x240 net/sched/sch_taprio.c:125 rcu_do_batch kernel/rcu/tree.c:2489 [inline] rcu_core+0x75d/0xf80 kernel/rcu/tree.c:2723 __do_softirq+0x2bc/0xa77 kernel/softirq.c:343 Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xdc/0x100 mm/kasan/generic.c:343 __call_rcu kernel/rcu/tree.c:2965 [inline] call_rcu+0xbb/0x710 kernel/rcu/tree.c:3038 taprio_change+0x2362/0x2e90 net/sched/sch_taprio.c:1579 qdisc_change net/sched/sch_api.c:1331 [inline] tc_modify_qdisc+0xd4e/0x1a30 net/sched/sch_api.c:1633 rtnetlink_rcv_msg+0x498/0xb80 net/core/rtnetlink.c:5564 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x907/0xe40 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_no_sendpage+0xee/0x130 net/core/sock.c:2846 kernel_sendpage.part.0+0x1cb/0x380 net/socket.c:3636 kernel_sendpage net/socket.c:3633 [inline] sock_sendpage+0xe5/0x140 net/socket.c:945 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x45e/0x8c0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] do_splice+0xb7b/0x1aa0 fs/splice.c:1059 __do_splice+0x134/0x250 fs/splice.c:1137 __do_sys_splice fs/splice.c:1343 [inline] __se_sys_splice fs/splice.c:1325 [inline] __x64_sys_splice+0x198/0x250 fs/splice.c:1325 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xdc/0x100 mm/kasan/generic.c:343 __call_rcu kernel/rcu/tree.c:2965 [inline] call_rcu+0xbb/0x710 kernel/rcu/tree.c:3038 ip_fib_net_exit+0x1bd/0x2b0 net/ipv4/fib_frontend.c:1562 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:187 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 The buggy address belongs to the object at ffff888019176280 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 64 bytes inside of 96-byte region [ffff888019176280, ffff8880191762e0) The buggy address belongs to the page: page:000000008771145c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x19176 flags: 0xfff00000000200(slab) raw: 00fff00000000200 dead000000000100 dead000000000122 ffff888010841780 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888019176180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888019176200: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888019176280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888019176300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888019176380: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ==================================================================