RDX: 0492492492492642 RSI: 0000000020000180 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000bb1414ac R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff R13: 000000000000000a R14: 0000000000000000 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:704 [inline] BUG: KASAN: use-after-free in qdisc_class_hash_insert+0x25e/0x270 net/sched/sch_api.c:694 Write of size 8 at addr ffff88809ce1f9d0 by task syz-executor746/7503 CPU: 1 PID: 7503 Comm: syz-executor746 Not tainted 4.14.174-syzkaller #0 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+0x13e/0x194 lib/dump_stack.c:58 print_address_description.cold+0x7c/0x1e2 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2ae mm/kasan/report.c:393 hlist_add_head include/linux/list.h:704 [inline] qdisc_class_hash_insert+0x25e/0x270 net/sched/sch_api.c:694 qfq_change_class+0x88f/0x1081 net/sched/sch_qfq.c:500 tc_ctl_tclass+0x3e2/0xa00 net/sched/sch_api.c:1848 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315 netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x620 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x733/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xc5/0x100 net/socket.c:656 ___sys_sendmsg+0x349/0x840 net/socket.c:2062 __sys_sendmmsg+0x129/0x330 net/socket.c:2152 SYSC_sendmmsg net/socket.c:2183 [inline] SyS_sendmmsg+0x2f/0x50 net/socket.c:2178 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443da9 RSP: 002b:00007fff4325eea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fff4325ef20 RCX: 0000000000443da9 RDX: 0492492492492642 RSI: 0000000020000180 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000bb1414ac R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff R13: 000000000000000a R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7503: save_stack+0x32/0xa0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:529 kmem_cache_alloc_trace+0x14d/0x7b0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] qfq_change_class+0x64e/0x1081 net/sched/sch_qfq.c:475 tc_ctl_tclass+0x3e2/0xa00 net/sched/sch_api.c:1848 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315 netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x620 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x733/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xc5/0x100 net/socket.c:656 ___sys_sendmsg+0x349/0x840 net/socket.c:2062 __sys_sendmmsg+0x129/0x330 net/socket.c:2152 SYSC_sendmmsg net/socket.c:2183 [inline] SyS_sendmmsg+0x2f/0x50 net/socket.c:2178 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 7503: save_stack+0x32/0xa0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcb/0x260 mm/slab.c:3815 qfq_change_class+0xd82/0x1081 net/sched/sch_qfq.c:529 tc_ctl_tclass+0x3e2/0xa00 net/sched/sch_api.c:1848 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315 netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x620 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x733/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xc5/0x100 net/socket.c:656 ___sys_sendmsg+0x349/0x840 net/socket.c:2062 __sys_sendmmsg+0x129/0x330 net/socket.c:2152 SYSC_sendmmsg net/socket.c:2183 [inline] SyS_sendmmsg+0x2f/0x50 net/socket.c:2178 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff88809ce1f9c0 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 16 bytes inside of 128-byte region [ffff88809ce1f9c0, ffff88809ce1fa40) The buggy address belongs to the page: page:ffffea00027387c0 count:1 mapcount:0 mapping:ffff88809ce1f000 index:0x0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffff88809ce1f000 0000000000000000 0000000100000015 raw: ffffea000272b3e0 ffffea000294bb20 ffff88812fe56640 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809ce1f880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88809ce1f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809ce1f980: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff88809ce1fa00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88809ce1fa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ==================================================================