================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_long_read include/linux/atomic/atomic-instrumented.h:1183 [inline] BUG: KASAN: use-after-free in __down_read_trylock kernel/locking/rwsem.c:1348 [inline] BUG: KASAN: use-after-free in down_read_trylock+0xb5/0x7d0 kernel/locking/rwsem.c:1624 Read of size 8 at addr ffff88810d341070 by task kworker/u4:0/8 CPU: 1 PID: 8 Comm: kworker/u4:0 Not tainted 5.15.178-syzkaller-00193-g058abb720bd1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106 print_address_description+0x87/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:444 kasan_check_range+0x293/0x2a0 mm/kasan/generic.c:189 __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_long_read include/linux/atomic/atomic-instrumented.h:1183 [inline] __down_read_trylock kernel/locking/rwsem.c:1348 [inline] down_read_trylock+0xb5/0x7d0 kernel/locking/rwsem.c:1624 trylock_super+0x1f/0xf0 fs/super.c:418 __writeback_inodes_wb+0x101/0x3f0 fs/fs-writeback.c:1992 wb_writeback+0x3da/0x9f0 fs/fs-writeback.c:2108 wb_check_old_data_flush fs/fs-writeback.c:2212 [inline] wb_do_writeback fs/fs-writeback.c:2265 [inline] wb_workfn+0xb3d/0x1110 fs/fs-writeback.c:2294 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 kthread+0x421/0x510 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 7295: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc+0xdb/0x110 mm/kasan/common.c:512 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] __kmalloc+0x13f/0x2c0 mm/slub.c:4431 kmalloc include/linux/slab.h:608 [inline] kzalloc include/linux/slab.h:733 [inline] __register_sysctl_table+0xea/0x1240 fs/proc/proc_sysctl.c:1319 register_net_sysctl+0x21e/0x230 net/sysctl_net.c:169 __addrconf_sysctl_register+0x28f/0x3e0 net/ipv6/addrconf.c:7139 addrconf_sysctl_register+0x141/0x1a0 net/ipv6/addrconf.c:7186 ipv6_add_dev+0xc84/0x1140 net/ipv6/addrconf.c:454 addrconf_notify+0x593/0xdd0 net/ipv6/addrconf.c:3599 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x8c/0xf0 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2026 [inline] call_netdevice_notifiers_extack net/core/dev.c:2038 [inline] call_netdevice_notifiers+0x145/0x1b0 net/core/dev.c:2052 register_netdevice+0x1035/0x1390 net/core/dev.c:10404 register_netdev+0x3c/0x50 net/core/dev.c:10497 ip6_tnl_init_net+0x2da/0x390 net/ipv6/ip6_tunnel.c:2286 ops_init+0x1cd/0x4a0 net/core/net_namespace.c:138 setup_net+0x34b/0xb50 net/core/net_namespace.c:332 copy_net_ns+0x35f/0x5b0 net/core/net_namespace.c:476 create_new_namespaces+0x416/0x670 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:226 ksys_unshare+0x545/0x980 kernel/fork.c:3166 __do_sys_unshare kernel/fork.c:3240 [inline] __se_sys_unshare kernel/fork.c:3238 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3238 x64_sys_call+0x728/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:273 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 987: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x126/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0xbd/0x190 mm/slub.c:1749 slab_free mm/slub.c:3521 [inline] kmem_cache_free_bulk+0x304/0x770 mm/slub.c:3664 kfree_bulk include/linux/slab.h:460 [inline] kfree_rcu_work+0x2b2/0x6a0 kernel/rcu/tree.c:3330 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 kthread+0x421/0x510 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 kvfree_call_rcu+0xb1/0x8b0 kernel/rcu/tree.c:3644 drop_sysctl_table+0x311/0x450 fs/proc/proc_sysctl.c:1680 unregister_sysctl_table+0x7b/0x120 fs/proc/proc_sysctl.c:1718 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:175 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7168 [inline] addrconf_sysctl_unregister net/ipv6/addrconf.c:7196 [inline] addrconf_ifdown+0x178f/0x1ae0 net/ipv6/addrconf.c:3951 addrconf_notify+0x37d/0xdd0 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x8c/0xf0 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2026 [inline] call_netdevice_notifiers_extack net/core/dev.c:2038 [inline] call_netdevice_notifiers net/core/dev.c:2052 [inline] unregister_netdevice_many+0xe0a/0x17c0 net/core/dev.c:11118 ip6_tnl_exit_batch_net+0x3c4/0x410 net/ipv6/ip6_tunnel.c:2309 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x6ce/0xc00 net/core/net_namespace.c:599 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 kthread+0x421/0x510 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 insert_work+0x56/0x320 kernel/workqueue.c:1373 __queue_work+0x92a/0xcd0 kernel/workqueue.c:1539 queue_work_on+0x105/0x170 kernel/workqueue.c:1566 queue_work include/linux/workqueue.h:510 [inline] schedule_work include/linux/workqueue.h:571 [inline] destroy_super_rcu+0xd1/0xe0 fs/super.c:172 rcu_do_batch+0x57a/0xc10 kernel/rcu/tree.c:2523 rcu_core+0x517/0x1020 kernel/rcu/tree.c:2763 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776 handle_softirqs+0x25e/0x5c0 kernel/softirq.c:565 __do_softirq kernel/softirq.c:603 [inline] invoke_softirq kernel/softirq.c:425 [inline] __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:652 irq_exit_rcu+0x9/0x10 kernel/softirq.c:664 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676 The buggy address belongs to the object at ffff88810d341000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 112 bytes inside of 2048-byte region [ffff88810d341000, ffff88810d341800) The buggy address belongs to the page: page:ffffea000434d000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10d340 head:ffffea000434d000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043200 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 291, ts 22275979427, free_ts 22226617252 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1b/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5780 allocate_slab mm/slub.c:1932 [inline] new_slab+0x9a/0x4e0 mm/slub.c:1995 ___slab_alloc+0x39e/0x830 mm/slub.c:3028 __slab_alloc+0x4a/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] __kmalloc_track_caller+0x171/0x2c0 mm/slub.c:4949 kmalloc_reserve net/core/skbuff.c:357 [inline] pskb_expand_head+0x113/0x1240 net/core/skbuff.c:1733 netlink_trim+0x19b/0x230 net/netlink/af_netlink.c:1297 netlink_broadcast_filtered+0x66/0x1220 net/netlink/af_netlink.c:1502 netlink_broadcast net/netlink/af_netlink.c:1547 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x101/0x1c0 net/netlink/af_netlink.c:2536 rtnl_notify net/core/rtnetlink.c:759 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3905 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3920 [inline] rtmsg_ifinfo+0xe7/0x120 net/core/rtnetlink.c:3926 __dev_notify_flags+0xdd/0x610 net/core/dev.c:8863 __rtnl_newlink net/core/rtnetlink.c:3529 [inline] rtnl_newlink+0x1a16/0x2050 net/core/rtnetlink.c:3569 rtnetlink_rcv_msg+0x951/0xc40 net/core/rtnetlink.c:5647 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3534 free_unref_page+0xe8/0x750 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5856 __free_slab+0xec/0x1d0 mm/slub.c:2020 free_slab mm/slub.c:2035 [inline] discard_slab mm/slub.c:2041 [inline] __unfreeze_partials+0x165/0x1a0 mm/slub.c:2527 put_cpu_partial+0xc4/0x120 mm/slub.c:2607 __slab_free+0x1c8/0x290 mm/slub.c:3390 do_slab_free mm/slub.c:3509 [inline] ___cache_free+0x109/0x120 mm/slub.c:3530 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157 qlist_free_all+0x44/0xb0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x15a/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:443 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550 slab_alloc_node mm/slub.c:3240 [inline] slab_alloc mm/slub.c:3250 [inline] __kmalloc_track_caller+0x11d/0x2c0 mm/slub.c:4949 kvasprintf+0xd6/0x180 lib/kasprintf.c:25 kvasprintf_const+0x5e/0x190 lib/kasprintf.c:49 Memory state around the buggy address: ffff88810d340f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810d340f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88810d341000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810d341080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810d341100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================