netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. ================================================================== BUG: KASAN: use-after-free in tcindex_dump+0xbea/0xbf0 net/sched/cls_tcindex.c:637 Read of size 8 at addr ffff888090ad42a0 by task syz-executor.0/9629 CPU: 1 PID: 9629 Comm: syz-executor.0 Not tainted 4.14.298-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 tcindex_dump+0xbea/0xbf0 net/sched/cls_tcindex.c:637 tcf_fill_node+0x529/0x810 net/sched/cls_api.c:453 tfilter_notify+0x11c/0x240 net/sched/cls_api.c:476 tc_ctl_tfilter+0x11af/0x1c10 net/sched/cls_api.c:743 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4322 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454 netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x326/0x800 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+0x5e/0xd3 Allocated by task 9629: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc_array include/linux/slab.h:607 [inline] kcalloc include/linux/slab.h:618 [inline] tcindex_alloc_perfect_hash+0x53/0x3c0 net/sched/cls_tcindex.c:299 tcindex_set_parms+0x13fd/0x17c0 net/sched/cls_tcindex.c:428 tcindex_change+0x1c1/0x2c0 net/sched/cls_tcindex.c:539 tc_ctl_tfilter+0xb54/0x1c10 net/sched/cls_api.c:738 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4322 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454 netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x326/0x800 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+0x5e/0xd3 Freed by task 17: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 __tcindex_partial_destroy+0x2e/0x50 net/sched/cls_tcindex.c:282 __rcu_reclaim kernel/rcu/rcu.h:195 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x780/0x1180 kernel/rcu/tree.c:2946 __do_softirq+0x24d/0x9ff kernel/softirq.c:288 The buggy address belongs to the object at ffff888090ad4280 which belongs to the cache kmalloc-8192 of size 8192 The buggy address is located 32 bytes inside of 8192-byte region [ffff888090ad4280, ffff888090ad6280) The buggy address belongs to the page: page:ffffea000242b500 count:1 mapcount:0 mapping:ffff888090ad4280 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff888090ad4280 0000000000000000 0000000100000001 raw: ffffea00024eec20 ffffea00019cd220 ffff88813fe65080 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888090ad4180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888090ad4200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888090ad4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888090ad4300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888090ad4380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================