IPVS: ftp: loaded support on port[0] = 21 ================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff88808dfc3ccb by task syz-executor5/11923 CPU: 0 PID: 11923 Comm: syz-executor5 Not tainted 4.20.0+ #3 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+0x1db/0x2d0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443 batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] dev_direct_xmit+0x368/0x670 net/core/dev.c:3930 packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x2753/0x6830 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 sock_write_iter+0x379/0x5e0 net/socket.c:900 call_write_iter include/linux/fs.h:1857 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6e5/0xa80 fs/read_write.c:487 vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0x105/0x260 fs/read_write.c:598 IPVS: ftp: loaded support on port[0] = 21 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fd2c16c6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 000000000000000e RSI: 0000000020000000 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd2c16c76d4 R13: 00000000004c3bad R14: 00000000004dbf08 R15: 00000000ffffffff Allocated by task 93: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc_node+0x144/0x710 mm/slab.c:3644 alloc_task_struct_node kernel/fork.c:158 [inline] dup_task_struct kernel/fork.c:848 [inline] copy_process+0x40bc/0x8730 kernel/fork.c:1756 _do_fork+0x1a9/0x1170 kernel/fork.c:2221 kernel_thread+0x34/0x40 kernel/fork.c:2280 call_usermodehelper_exec_sync kernel/umh.c:130 [inline] call_usermodehelper_exec_work+0xcb/0x2f0 kernel/umh.c:182 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Freed by task 16: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3760 free_task_struct kernel/fork.c:163 [inline] free_task+0x170/0x1f0 kernel/fork.c:462 __put_task_struct+0x2e0/0x630 kernel/fork.c:735 put_task_struct include/linux/sched/task.h:96 [inline] delayed_put_task_struct+0x2fd/0x4d0 kernel/exit.c:181 __rcu_reclaim kernel/rcu/rcu.h:240 [inline] rcu_do_batch kernel/rcu/tree.c:2452 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline] rcu_process_callbacks+0xc4a/0x1680 kernel/rcu/tree.c:2754 kobject: 'rx-0' (00000000da77cada): kobject_uevent_env __do_softirq+0x30b/0xb11 kernel/softirq.c:292 The buggy address belongs to the object at ffff88808dfc2640 which belongs to the cache task_struct of size 6080 The buggy address is located 5771 bytes inside of 6080-byte region [ffff88808dfc2640, ffff88808dfc3e00) The buggy address belongs to the page: page:ffffea000237f080 count:1 mapcount:0 mapping:ffff88821bc404c0 index:0x0 compound_mapcount: 0 kobject: 'rx-0' (00000000da77cada): fill_kobj_path: path = '/devices/virtual/net/tunl0/queues/rx-0' flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001a04f08 ffffea0001a3de88 ffff88821bc404c0 kobject: 'tx-0' (00000000e9e11ed1): kobject_add_internal: parent: 'queues', set: 'queues' raw: 0000000000000000 ffff88808dfc2640 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808dfc3b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808dfc3c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808dfc3c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808dfc3d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb kobject: 'tx-0' (00000000e9e11ed1): kobject_uevent_env ffff88808dfc3d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================