cgroup: fork rejected by pids controller in /syz4 ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:72 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline] BUG: KASAN: use-after-free in __refcount_add_not_zero include/linux/refcount.h:152 [inline] BUG: KASAN: use-after-free in __refcount_inc_not_zero include/linux/refcount.h:227 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero include/linux/refcount.h:245 [inline] BUG: KASAN: use-after-free in io_worker_get+0x77/0x2a0 io_uring/io-wq.c:153 Read of size 4 at addr ffff888055a3e800 by task syz-executor.4/19016 CPU: 0 PID: 19016 Comm: syz-executor.4 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 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] refcount_read include/linux/refcount.h:147 [inline] __refcount_add_not_zero include/linux/refcount.h:152 [inline] __refcount_inc_not_zero include/linux/refcount.h:227 [inline] refcount_inc_not_zero include/linux/refcount.h:245 [inline] io_worker_get+0x77/0x2a0 io_uring/io-wq.c:153 io_wq_for_each_worker io_uring/io-wq.c:846 [inline] io_wq_exit_workers io_uring/io-wq.c:1250 [inline] io_wq_put_and_exit+0x2f8/0xcb0 io_uring/io-wq.c:1289 io_uring_clean_tctx+0x164/0x1d0 io_uring/tctx.c:193 io_uring_cancel_generic+0x60e/0x670 io_uring/io_uring.c:3145 io_uring_files_cancel include/linux/io_uring.h:55 [inline] do_exit+0x2ad/0x2150 kernel/exit.c:822 do_group_exit+0x1fd/0x2b0 kernel/exit.c:1012 get_signal+0x1755/0x1820 kernel/signal.c:2859 arch_do_signal_or_restart+0x8d/0x5f0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x74/0x160 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xad/0x110 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x2e/0x60 kernel/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fec2f68c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fec2e1fe168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007fec2f7ac050 RCX: 00007fec2f68c0c9 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007fec2f6e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffccaa88d9f R14: 00007fec2e1fe300 R15: 0000000000022000 Allocated by task 19016: 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 io_wqe_create_worker io_uring/io-wq.c:310 [inline] io_wqe_enqueue+0x9f3/0xd10 io_uring/io-wq.c:936 io_queue_iowq+0x2ac/0x3a0 io_uring/io_uring.c:475 io_queue_async+0x42b/0x600 io_uring/io_uring.c:2013 io_poll_task_func+0xd48/0x10c0 io_uring/poll.c:346 handle_tw_list io_uring/io_uring.c:1147 [inline] tctx_task_work+0x37e/0xa90 io_uring/io_uring.c:1202 task_work_run+0x243/0x300 kernel/task_work.c:179 get_signal+0x1654/0x1820 kernel/signal.c:2635 arch_do_signal_or_restart+0x8d/0x5f0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x74/0x160 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xad/0x110 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x2e/0x60 kernel/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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 wait_woken+0xca/0x1b0 kernel/sched/wait.c:463 tipc_wait_for_rcvmsg+0x321/0x660 net/tipc/socket.c:1850 tipc_recvmsg+0x221/0x1500 net/tipc/socket.c:1912 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+0x535/0x9c0 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 ipv6_mc_destroy_dev+0x345/0x6b0 net/ipv6/mcast.c:2800 addrconf_ifdown+0x1740/0x1bc0 net/ipv6/addrconf.c:3893 addrconf_notify+0x3b9/0x1010 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1944 [inline] call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] unregister_netdevice_many_notify+0x102e/0x1c20 net/core/dev.c:10839 vti6_exit_batch_net+0x3b2/0x400 net/ipv6/ip6_vti.c:1188 ops_exit_list net/core/net_namespace.c:174 [inline] cleanup_net+0x80c/0xc60 net/core/net_namespace.c:606 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 The buggy address belongs to the object at ffff888055a3e800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff888055a3e800, ffff888055a3ea00) The buggy address belongs to the physical page: page:ffffea0001568f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888055a3f800 pfn:0x55a3c head:ffffea0001568f00 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012841c80 ffffea0001502810 ffffea00014fcc10 raw: ffff888055a3f800 0000000000100008 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5072, tgid 5072 (syz-executor.2), ts 63146289630, free_ts 12839511823 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_netconf_notify_devconf+0xf8/0x1b0 net/ipv6/addrconf.c:581 __addrconf_sysctl_register+0x35f/0x3c0 net/ipv6/addrconf.c:7093 addrconf_sysctl_register+0x128/0x180 net/ipv6/addrconf.c:7130 ipv6_add_dev+0xb9d/0x1150 net/ipv6/addrconf.c:450 addrconf_notify+0x782/0x1010 net/ipv6/addrconf.c:3528 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1944 [inline] call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers+0x14e/0x1d0 net/core/dev.c:1996 register_netdevice+0x15e4/0x1a30 net/core/dev.c:10078 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 free_contig_range+0xa3/0x160 mm/page_alloc.c:9485 destroy_args+0xfe/0x990 mm/debug_vm_pgtable.c:998 debug_vm_pgtable+0x453/0x4b0 mm/debug_vm_pgtable.c:1318 do_one_initcall+0xbd/0x2c0 init/main.c:1306 do_initcall_level+0x168/0x220 init/main.c:1379 do_initcalls+0x43/0x90 init/main.c:1395 kernel_init_freeable+0x471/0x620 init/main.c:1634 kernel_init+0x19/0x2b0 init/main.c:1522 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Memory state around the buggy address: ffff888055a3e700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888055a3e780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888055a3e800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888055a3e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055a3e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================