================================================================== BUG: KASAN: slab-use-after-free in pwq_release_workfn+0x253/0x260 kernel/workqueue.c:4124 Read of size 4 at addr ffff8880696b99c0 by task pool_workqueue_/3 CPU: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.5.0-syzkaller-10885-g0468be89b3fa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 pwq_release_workfn+0x253/0x260 kernel/workqueue.c:4124 kthread_worker_fn+0x49a/0x9f0 kernel/kthread.c:823 kthread+0x2b8/0x350 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Allocated by task 28981: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_workqueue+0x172/0x1520 kernel/workqueue.c:4684 wg_newlink+0x34e/0x710 drivers/net/wireguard/device.c:343 rtnl_newlink_create net/core/rtnetlink.c:3485 [inline] __rtnl_newlink net/core/rtnetlink.c:3705 [inline] rtnl_newlink+0x1579/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x82b/0xf50 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2540 ___sys_sendmsg net/socket.c:2594 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 28981: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3822 alloc_workqueue+0xeba/0x1520 kernel/workqueue.c:4746 wg_newlink+0x34e/0x710 drivers/net/wireguard/device.c:343 rtnl_newlink_create net/core/rtnetlink.c:3485 [inline] __rtnl_newlink net/core/rtnetlink.c:3705 [inline] rtnl_newlink+0x1579/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x82b/0xf50 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2540 ___sys_sendmsg net/socket.c:2594 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xad/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2653 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:2767 kthread_worker_fn+0x49a/0x9f0 kernel/kthread.c:823 kthread+0x2b8/0x350 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Second to last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xad/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xf8/0x790 kernel/rcu/tree.c:3372 drop_sysctl_table+0x386/0x4f0 fs/proc/proc_sysctl.c:1508 drop_sysctl_table+0x398/0x4f0 fs/proc/proc_sysctl.c:1511 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1529 neigh_sysctl_unregister+0x78/0xa0 net/core/neighbour.c:3868 addrconf_sysctl_unregister net/ipv6/addrconf.c:7198 [inline] addrconf_ifdown+0x18a8/0x1b90 net/ipv6/addrconf.c:3945 addrconf_notify+0x1b1/0x1010 notifier_call_chain+0x18c/0x3a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1970 [inline] call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] unregister_netdevice_many_notify+0xe1f/0x1900 net/core/dev.c:10938 rtnl_newlink_create net/core/rtnetlink.c:3516 [inline] __rtnl_newlink net/core/rtnetlink.c:3705 [inline] rtnl_newlink+0x1d4f/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x82b/0xf50 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2540 ___sys_sendmsg net/socket.c:2594 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880696b9800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 448 bytes inside of freed 512-byte region [ffff8880696b9800, ffff8880696b9a00) The buggy address belongs to the physical page: page:ffffea0001a5ae00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x696b8 head:ffffea0001a5ae00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012841c80 dead000000000100 dead000000000122 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 19984, tgid 19981 (syz-executor.3), ts 1026720892120, free_ts 1016803785405 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31ec/0x3370 mm/page_alloc.c:3183 __alloc_pages+0x255/0x670 mm/page_alloc.c:4439 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xade/0x1100 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [inline] copy_splice_read+0x192/0x9c0 fs/splice.c:338 splice_direct_to_actor+0x2c4/0x9e0 fs/splice.c:1069 do_splice_direct+0x2ac/0x3f0 fs/splice.c:1194 do_sendfile+0x623/0x1070 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 kasan_depopulate_vmalloc_pte+0x74/0x90 mm/kasan/shadow.c:427 apply_to_pte_range mm/memory.c:2586 [inline] apply_to_pmd_range mm/memory.c:2630 [inline] apply_to_pud_range mm/memory.c:2666 [inline] apply_to_p4d_range mm/memory.c:2702 [inline] __apply_to_page_range+0x8e2/0xdf0 mm/memory.c:2736 kasan_release_vmalloc+0x9a/0xb0 mm/kasan/shadow.c:544 __purge_vmap_area_lazy+0xc0f/0x19c0 mm/vmalloc.c:1770 drain_vmap_area_work+0x40/0xd0 mm/vmalloc.c:1804 process_one_work+0x781/0x1130 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0xabf/0x1060 kernel/workqueue.c:2784 kthread+0x2b8/0x350 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Memory state around the buggy address: ffff8880696b9880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880696b9900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880696b9980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880696b9a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880696b9a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================