netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. ================================================================== BUG: KASAN: use-after-free in rhashtable_rehash_one lib/rhashtable.c:276 [inline] BUG: KASAN: use-after-free in rhashtable_rehash_chain lib/rhashtable.c:316 [inline] BUG: KASAN: use-after-free in rhashtable_rehash_table lib/rhashtable.c:364 [inline] BUG: KASAN: use-after-free in rht_deferred_worker+0x1366/0x1890 lib/rhashtable.c:465 Read of size 8 at addr ffff8880b038ec80 by task kworker/1:4/10508 CPU: 1 PID: 10508 Comm: kworker/1:4 Not tainted 4.14.223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events rht_deferred_worker 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 rhashtable_rehash_one lib/rhashtable.c:276 [inline] rhashtable_rehash_chain lib/rhashtable.c:316 [inline] rhashtable_rehash_table lib/rhashtable.c:364 [inline] rht_deferred_worker+0x1366/0x1890 lib/rhashtable.c:465 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Allocated by task 25928: 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 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] fl_change+0x27e/0x4830 net/sched/cls_flower.c:919 tc_ctl_tfilter+0xb54/0x1c10 net/sched/cls_api.c:738 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 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+0x46/0xbb Freed by task 9274: 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 fl_destroy_filter_work+0x1a/0x20 net/sched/cls_flower.c:234 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 The buggy address belongs to the object at ffff8880b038ec80 which belongs to the cache kmalloc-512 of size 512 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. The buggy address is located 0 bytes inside of 512-byte region [ffff8880b038ec80, ffff8880b038ee80) The buggy address belongs to the page: page:ffffea0002c0e380 count:1 mapcount:0 mapping:ffff8880b038e000 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880b038e000 0000000000000000 0000000100000006 raw: ffffea0002baa7e0 ffffea0002d18f20 ffff88813fe80940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b038eb80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8880b038ec00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880b038ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880b038ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880b038ed80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================