================================================================== 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+0x91/0x660 kernel/locking/rwsem.c:1624 Read of size 8 at addr ffff8881128a9070 by task kworker/u4:9/8454 CPU: 1 PID: 8454 Comm: kworker/u4:9 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 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+0x91/0x660 kernel/locking/rwsem.c:1624 trylock_super+0x1f/0xf0 fs/super.c:418 __writeback_inodes_wb+0x119/0x400 fs/fs-writeback.c:2002 wb_writeback+0x403/0x980 fs/fs-writeback.c:2118 wb_check_old_data_flush fs/fs-writeback.c:2222 [inline] wb_do_writeback fs/fs-writeback.c:2275 [inline] wb_workfn+0x9ae/0xe20 fs/fs-writeback.c:2304 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472 kthread+0x411/0x500 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 9553: 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 mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] __kmalloc+0x13d/0x2c0 mm/slub.c:4436 kmalloc include/linux/slab.h:624 [inline] f2fs_kmalloc fs/f2fs/f2fs.h:3382 [inline] f2fs_fill_super+0x28c0/0x6d10 fs/f2fs/super.c:4294 mount_bdev+0x2ae/0x3e0 fs/super.c:1400 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4705 legacy_get_tree+0xed/0x190 fs/fs_context.c:611 vfs_get_tree+0x89/0x260 fs/super.c:1530 do_new_mount+0x25a/0xa20 fs/namespace.c:3034 path_mount+0x675/0x1020 fs/namespace.c:3364 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x318/0x380 fs/namespace.c:3562 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3562 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 282: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 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:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kfree+0xc4/0x270 mm/slub.c:4588 kvfree+0x35/0x40 mm/util.c:661 f2fs_put_super+0x9dc/0xc00 fs/f2fs/super.c:1727 generic_shutdown_super+0x151/0x330 fs/super.c:475 kill_block_super+0x7f/0xf0 fs/super.c:1427 kill_f2fs_super+0x2e7/0x390 fs/f2fs/super.c:4737 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1148 __cleanup_mnt+0x19/0x20 fs/namespace.c:1155 task_work_run+0x127/0x190 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 insert_work+0x51/0x310 kernel/workqueue.c:1373 __queue_work+0x8e5/0xc60 kernel/workqueue.c:1539 queue_work_on+0xd2/0x140 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+0x51d/0xba0 kernel/rcu/tree.c:2523 rcu_core+0x5e4/0xf80 kernel/rcu/tree.c:2763 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776 handle_softirqs+0x250/0x560 kernel/softirq.c:583 __do_softirq kernel/softirq.c:621 [inline] invoke_softirq kernel/softirq.c:443 [inline] __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:670 irq_exit_rcu+0x9/0x10 kernel/softirq.c:682 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 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu_common kernel/rcu/tree.c:3011 [inline] call_rcu+0x105/0xfe0 kernel/rcu/tree.c:3129 __put_super+0x26b/0x2d0 fs/super.c:299 put_super fs/super.c:313 [inline] deactivate_locked_super+0xd4/0x100 fs/super.c:346 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1148 __cleanup_mnt+0x19/0x20 fs/namespace.c:1155 task_work_run+0x127/0x190 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa7e/0x27a0 kernel/exit.c:889 do_group_exit+0x141/0x310 kernel/exit.c:1003 __do_sys_exit_group kernel/exit.c:1014 [inline] __se_sys_exit_group kernel/exit.c:1012 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1012 x64_sys_call+0x832/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff8881128a9000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 112 bytes inside of 2048-byte region [ffff8881128a9000, ffff8881128a9800) The buggy address belongs to the page: page:ffffea00044a2a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1128a8 head:ffffea00044a2a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 0000000100000001 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4164, ts 319417002568, free_ts 316577126773 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5808 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa1/0x4d0 mm/slub.c:2000 ___slab_alloc+0x381/0x810 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] __kmalloc+0x16a/0x2c0 mm/slub.c:4432 kmalloc include/linux/slab.h:624 [inline] kzalloc include/linux/slab.h:750 [inline] ops_init+0x89/0x4a0 net/core/net_namespace.c:128 setup_net+0x344/0xa90 net/core/net_namespace.c:332 copy_net_ns+0x355/0x5c0 net/core/net_namespace.c:476 create_new_namespaces+0x3a2/0x660 kernel/nsproxy.c:110 copy_namespaces+0x1d1/0x220 kernel/nsproxy.c:178 copy_process+0x118d/0x3210 kernel/fork.c:2351 kernel_clone+0x23f/0x940 kernel/fork.c:2737 __do_sys_clone kernel/fork.c:2863 [inline] __se_sys_clone kernel/fork.c:2847 [inline] __x64_sys_clone+0x176/0x1d0 kernel/fork.c:2847 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+0x542/0x550 mm/page_alloc.c:3534 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5884 __free_slab+0xe8/0x1e0 mm/slub.c:2025 free_slab mm/slub.c:2040 [inline] discard_slab+0x29/0x40 mm/slub.c:2046 __slab_free+0x211/0x290 mm/slub.c:3431 do_slab_free mm/slub.c:3514 [inline] ___cache_free+0x104/0x120 mm/slub.c:3535 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:443 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550 slab_alloc_node mm/slub.c:3245 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260 sock_alloc_inode+0x1b/0xb0 net/socket.c:303 alloc_inode fs/inode.c:264 [inline] new_inode_pseudo+0x62/0x210 fs/inode.c:1011 sock_alloc net/socket.c:626 [inline] __sock_create+0x12c/0x7a0 net/socket.c:1450 Memory state around the buggy address: ffff8881128a8f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881128a8f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881128a9000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881128a9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881128a9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================