================================================================== BUG: KASAN: slab-use-after-free in __up_write kernel/locking/rwsem.c:1364 [inline] BUG: KASAN: slab-use-after-free in up_write+0x6b/0x410 kernel/locking/rwsem.c:1626 Read of size 8 at addr ffff88802c5bc080 by task kworker/1:0/23 CPU: 1 PID: 23 Comm: kworker/1:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events f2fs_record_error_work Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 __up_write kernel/locking/rwsem.c:1364 [inline] up_write+0x6b/0x410 kernel/locking/rwsem.c:1626 f2fs_up_write fs/f2fs/f2fs.h:2206 [inline] f2fs_record_stop_reason fs/f2fs/super.c:4064 [inline] f2fs_record_error_work+0x144/0x1d0 fs/f2fs/super.c:4160 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 7922: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] f2fs_fill_super+0xca/0x6be0 fs/f2fs/super.c:4341 mount_bdev+0x221/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 7922: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 f2fs_fill_super+0x41b1/0x6be0 fs/f2fs/super.c:4809 mount_bdev+0x221/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x128/0x1f0 kernel/workqueue.c:1835 f2fs_submit_page_bio+0x1c3/0x650 fs/f2fs/data.c:694 __get_meta_page+0x1c1/0x5d0 fs/f2fs/checkpoint.c:87 f2fs_get_meta_page fs/f2fs/checkpoint.c:112 [inline] get_checkpoint_version+0x3c/0x330 fs/f2fs/checkpoint.c:851 validate_checkpoint+0x153/0x250 fs/f2fs/checkpoint.c:900 f2fs_get_valid_checkpoint+0x25e/0x940 fs/f2fs/checkpoint.c:939 f2fs_fill_super+0x3c5e/0x6be0 fs/f2fs/super.c:4478 mount_bdev+0x221/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88802c5bc000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 128 bytes inside of freed 8192-byte region [ffff88802c5bc000, ffff88802c5be000) The buggy address belongs to the physical page: page:ffffea0000b16e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2c5b8 head:ffffea0000b16e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c42280 ffffea000084b800 dead000000000003 raw: 0000000000000000 0000000080020002 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 23157641552, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] mr_table_alloc+0x65/0x240 net/ipv4/ipmr_base.c:41 ip6mr_new_table net/ipv6/ip6mr.c:401 [inline] ip6mr_rules_init net/ipv6/ip6mr.c:249 [inline] ip6mr_net_init+0x249/0x3b0 net/ipv6/ip6mr.c:1332 ops_init+0x397/0x640 net/core/net_namespace.c:139 __register_pernet_operations net/core/net_namespace.c:1220 [inline] register_pernet_operations+0x2b3/0x610 net/core/net_namespace.c:1293 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1334 ip6_mr_init+0x3e/0x150 net/ipv6/ip6mr.c:1397 inet6_init+0x229/0x6c0 net/ipv6/af_inet6.c:1130 page_owner free stack trace missing Memory state around the buggy address: ffff88802c5bbf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802c5bc000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802c5bc080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802c5bc100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c5bc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================