================================================================== BUG: KASAN: use-after-free in io_wq_worker_running+0xfe/0x130 io_uring/io-wq.c:674 Read of size 4 at addr ffff8880247d7804 by task iou-wrk-7357/7396 CPU: 0 PID: 7396 Comm: iou-wrk-7357 Not tainted 6.2.0-rc2-syzkaller-00256-ga689b938df39 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x74/0x340 mm/kasan/report.c:306 print_report+0x107/0x220 mm/kasan/report.c:417 kasan_report+0x139/0x170 mm/kasan/report.c:517 io_wq_worker_running+0xfe/0x130 io_uring/io-wq.c:674 schedule_timeout+0xac/0x300 kernel/time/timer.c:2143 __skb_wait_for_more_packets+0x38a/0x5e0 net/core/datagram.c:120 __skb_recv_datagram net/core/datagram.c:303 [inline] skb_recv_datagram+0x242/0x310 net/core/datagram.c:315 packet_recvmsg+0x142/0x1920 net/packet/af_packet.c:3439 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_read_iter+0x3fa/0x530 net/socket.c:1086 call_read_iter include/linux/fs.h:2183 [inline] io_iter_do_read io_uring/rw.c:643 [inline] io_read+0x4a8/0x1310 io_uring/rw.c:766 io_issue_sqe+0x44e/0xcd0 io_uring/io_uring.c:1856 io_wq_submit_work+0x44a/0x9c0 io_uring/io_uring.c:1932 io_worker_handle_work+0x8e1/0xee0 io_uring/io-wq.c:587 io_wqe_worker+0x36c/0xde0 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Allocated by task 7357: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:380 kmalloc_node include/linux/slab.h:606 [inline] kzalloc_node include/linux/slab.h:731 [inline] create_io_worker+0xef/0x630 io_uring/io-wq.c:801 create_worker_cb+0x16b/0x330 io_uring/io-wq.c:339 task_work_run+0x243/0x300 kernel/task_work.c:179 io_run_task_work+0xe9/0x120 io_uring/io_uring.h:275 io_run_task_work_ctx io_uring/io_uring.h:296 [inline] io_run_task_work_sig io_uring/io_uring.c:2463 [inline] io_cqring_wait_schedule io_uring/io_uring.c:2499 [inline] io_cqring_wait io_uring/io_uring.c:2567 [inline] __do_sys_io_uring_enter io_uring/io_uring.c:3390 [inline] __se_sys_io_uring_enter+0x1b68/0x2540 io_uring/io_uring.c:3277 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7396: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:518 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0x71/0x110 mm/slub.c:3800 io_wq_cancel_tw_create+0x77/0xd0 io_uring/io-wq.c:1233 io_queue_worker_create+0x384/0x430 io_uring/io-wq.c:381 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x63/0x190 kernel/sched/core.c:6628 schedule_timeout+0xac/0x300 kernel/time/timer.c:2143 __skb_wait_for_more_packets+0x38a/0x5e0 net/core/datagram.c:120 __skb_recv_datagram net/core/datagram.c:303 [inline] skb_recv_datagram+0x242/0x310 net/core/datagram.c:315 packet_recvmsg+0x142/0x1920 net/packet/af_packet.c:3439 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_read_iter+0x3fa/0x530 net/socket.c:1086 call_read_iter include/linux/fs.h:2183 [inline] io_iter_do_read io_uring/rw.c:643 [inline] io_read+0x4a8/0x1310 io_uring/rw.c:766 io_issue_sqe+0x44e/0xcd0 io_uring/io_uring.c:1856 io_wq_submit_work+0x44a/0x9c0 io_uring/io_uring.c:1932 io_worker_handle_work+0x8e1/0xee0 io_uring/io-wq.c:587 io_wqe_worker+0x36c/0xde0 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:488 task_work_add+0x87/0x340 kernel/task_work.c:48 io_queue_worker_create+0x1e2/0x430 io_uring/io-wq.c:373 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x63/0x190 kernel/sched/core.c:6628 schedule_timeout+0xac/0x300 kernel/time/timer.c:2143 __skb_wait_for_more_packets+0x38a/0x5e0 net/core/datagram.c:120 __skb_recv_datagram net/core/datagram.c:303 [inline] skb_recv_datagram+0x242/0x310 net/core/datagram.c:315 packet_recvmsg+0x142/0x1920 net/packet/af_packet.c:3439 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_read_iter+0x3fa/0x530 net/socket.c:1086 call_read_iter include/linux/fs.h:2183 [inline] io_iter_do_read io_uring/rw.c:643 [inline] io_read+0x4a8/0x1310 io_uring/rw.c:766 io_issue_sqe+0x44e/0xcd0 io_uring/io_uring.c:1856 io_wq_submit_work+0x44a/0x9c0 io_uring/io_uring.c:1932 io_worker_handle_work+0x8e1/0xee0 io_uring/io-wq.c:587 io_wqe_worker+0x36c/0xde0 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:488 kvfree_call_rcu+0x118/0x8c0 kernel/rcu/tree.c:3376 ma_put net/ipv6/mcast.c:869 [inline] __ipv6_dev_mc_dec+0x39a/0x420 net/ipv6/mcast.c:982 addrconf_leave_solict net/ipv6/addrconf.c:2192 [inline] __ipv6_ifa_notify+0x97e/0xec0 net/ipv6/addrconf.c:6173 addrconf_ifdown+0xf77/0x1bc0 net/ipv6/addrconf.c:3874 addrconf_notify+0x3b9/0x1010 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 __dev_notify_flags+0x339/0x630 dev_change_flags+0xe8/0x190 net/core/dev.c:8607 do_setlink+0xf36/0x3f10 net/core/rtnetlink.c:2827 rtnl_group_changelink net/core/rtnetlink.c:3344 [inline] __rtnl_newlink net/core/rtnetlink.c:3600 [inline] rtnl_newlink+0x115c/0x20a0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x7ca/0xec0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x1f0/0x470 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x7e7/0x9c0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x9b3/0xcd0 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x597/0x8e0 net/socket.c:2476 ___sys_sendmsg net/socket.c:2530 [inline] __sys_sendmsg+0x28e/0x390 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880247d7800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 4 bytes inside of 512-byte region [ffff8880247d7800, ffff8880247d7a00) The buggy address belongs to the physical page: page:ffffea000091f500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x247d4 head:ffffea000091f500 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 anon flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012841c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4719, tgid 4719 (kworker/0:3), ts 212151653087, free_ts 207370299120 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x72b/0x7a0 mm/page_alloc.c:4283 __alloc_pages+0x259/0x560 mm/page_alloc.c:5549 alloc_slab_page+0xbd/0x190 mm/slub.c:1851 allocate_slab+0x5e/0x3c0 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0x7f4/0xeb0 mm/slub.c:3193 __slab_alloc mm/slub.c:3292 [inline] __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x25b/0x340 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node_track_caller+0x9c/0x190 mm/slab_common.c:988 kmalloc_reserve net/core/skbuff.c:492 [inline] __alloc_skb+0x12c/0x2c0 net/core/skbuff.c:565 alloc_skb include/linux/skbuff.h:1270 [inline] nlmsg_new include/net/netlink.h:1002 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5496 [inline] __ipv6_ifa_notify+0x2a9/0xec0 net/ipv6/addrconf.c:6144 ipv6_ifa_notify net/ipv6/addrconf.c:6196 [inline] addrconf_dad_completed+0x188/0xca0 net/ipv6/addrconf.c:4209 addrconf_dad_work+0xdb4/0x16e0 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare+0x751/0x780 mm/page_alloc.c:1496 free_unref_page_prepare mm/page_alloc.c:3369 [inline] free_unref_page+0x19/0x4c0 mm/page_alloc.c:3464 discard_slab mm/slub.c:2098 [inline] __unfreeze_partials+0x1a5/0x1e0 mm/slub.c:2637 put_cpu_partial+0x116/0x180 mm/slub.c:2713 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:761 [inline] slab_alloc_node mm/slub.c:3452 [inline] __kmem_cache_alloc_node+0x1e0/0x340 mm/slub.c:3491 kmalloc_trace+0x26/0x60 mm/slab_common.c:1062 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] ____ip_mc_inc_group+0x2e9/0xae0 net/ipv4/igmp.c:1449 __ip_mc_inc_group net/ipv4/igmp.c:1484 [inline] ip_mc_inc_group net/ipv4/igmp.c:1490 [inline] ip_mc_up+0x119/0x2d0 net/ipv4/igmp.c:1789 inetdev_event+0xf19/0x1470 net/ipv4/devinet.c:1578 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 __dev_notify_flags+0x339/0x630 dev_change_flags+0xe8/0x190 net/core/dev.c:8607 do_setlink+0xf36/0x3f10 net/core/rtnetlink.c:2827 Memory state around the buggy address: ffff8880247d7700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880247d7780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880247d7800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880247d7880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880247d7900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================