BUG: Bad page state in process syz-executor  pfn:256f4
page:ffffea000095bd00 refcount:0 mapcount:0 mapping:ffff888077f027d8 index:0x2 pfn:0x256f4
aops:z_erofs_cache_aops ino:0
flags: 0xfff00000000001(locked|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000001 dead000000000100 dead000000000122 ffff888077f027d8
raw: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x192840(GFP_NOWAIT|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6345, tgid 6343 (syz.2.111), ts 148226991981, free_ts 148222279822
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1561 [inline]
 get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
 z_erofs_bind_cache fs/erofs/zdata.c:605 [inline]
 z_erofs_pcluster_begin fs/erofs/zdata.c:889 [inline]
 z_erofs_do_read_page+0x20c0/0x3680 fs/erofs/zdata.c:1024
 z_erofs_pcluster_readmore+0x2cf/0x450 fs/erofs/zdata.c:1833
 z_erofs_read_folio+0x208/0x540 fs/erofs/zdata.c:1853
 filemap_read_folio+0x167/0x760 mm/filemap.c:2420
 do_read_cache_folio+0x470/0x7e0 mm/filemap.c:3789
 erofs_bread+0x16f/0x630 fs/erofs/data.c:48
 erofs_find_target_block fs/erofs/namei.c:103 [inline]
 erofs_namei+0x28c/0xf00 fs/erofs/namei.c:177
 erofs_lookup+0x135/0x310 fs/erofs/namei.c:206
 lookup_open fs/namei.c:3466 [inline]
 open_last_lookups fs/namei.c:3556 [inline]
 path_openat+0x10b8/0x3190 fs/namei.c:3786
 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
 do_sys_open fs/open.c:1434 [inline]
 __do_sys_creat fs/open.c:1512 [inline]
 __se_sys_creat fs/open.c:1506 [inline]
 __x64_sys_creat+0x90/0xb0 fs/open.c:1506
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1154 [inline]
 free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 __slab_free+0x35e/0x410 mm/slub.c:3736
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4420
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049
 new_inode+0x22/0x1b0 fs/inode.c:1075
 __shmem_get_inode mm/shmem.c:2468 [inline]
 shmem_get_inode+0x34f/0xcc0 mm/shmem.c:2540
 shmem_mknod+0x60/0x1d0 mm/shmem.c:3233
 shmem_mkdir+0x33/0x60 mm/shmem.c:3298
 vfs_mkdir+0x296/0x440 fs/namei.c:4113
 do_mkdirat+0x1d4/0x440 fs/namei.c:4136
Modules linked in:
CPU: 0 PID: 5784 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 bad_page+0x14b/0x170 mm/page_alloc.c:512
 free_page_is_bad mm/page_alloc.c:961 [inline]
 free_pages_prepare mm/page_alloc.c:1146 [inline]
 free_unref_page_prepare+0x887/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 detach_page_private include/linux/pagemap.h:539 [inline]
 erofs_try_to_free_all_cached_pages+0x295/0x600 fs/erofs/zdata.c:657
 erofs_try_to_release_workgroup fs/erofs/utils.c:132 [inline]
 erofs_shrink_workstation+0x118/0x290 fs/erofs/utils.c:161
 erofs_shrinker_unregister+0x5d/0x170 fs/erofs/utils.c:198
 erofs_put_super+0x4e/0x150 fs/erofs/super.c:812
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1660
 erofs_kill_sb+0x4c/0x140 fs/erofs/super.c:794
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f869f9901f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdddd4ae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f869fa11d7d RCX: 00007f869f9901f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdddd4af20
RBP: 00007ffdddd4af20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdddd4bfb0
R13: 00007f869fa11d7d R14: 00000000000243c2 R15: 00007ffdddd4bff0
 </TASK>
BUG: Bad page state in process syz-executor  pfn:24695
page:ffffea000091a540 refcount:0 mapcount:0 mapping:ffff888077f027d8 index:0x3 pfn:0x24695
aops:z_erofs_cache_aops ino:0
flags: 0xfff00000000001(locked|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000001 dead000000000100 dead000000000122 ffff888077f027d8
raw: 0000000000000003 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x192840(GFP_NOWAIT|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6345, tgid 6343 (syz.2.111), ts 148227010931, free_ts 148222243053
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1561 [inline]
 get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
 z_erofs_bind_cache fs/erofs/zdata.c:605 [inline]
 z_erofs_pcluster_begin fs/erofs/zdata.c:889 [inline]
 z_erofs_do_read_page+0x20c0/0x3680 fs/erofs/zdata.c:1024
 z_erofs_pcluster_readmore+0x2cf/0x450 fs/erofs/zdata.c:1833
 z_erofs_read_folio+0x208/0x540 fs/erofs/zdata.c:1853
 filemap_read_folio+0x167/0x760 mm/filemap.c:2420
 do_read_cache_folio+0x470/0x7e0 mm/filemap.c:3789
 erofs_bread+0x16f/0x630 fs/erofs/data.c:48
 erofs_find_target_block fs/erofs/namei.c:103 [inline]
 erofs_namei+0x28c/0xf00 fs/erofs/namei.c:177
 erofs_lookup+0x135/0x310 fs/erofs/namei.c:206
 lookup_open fs/namei.c:3466 [inline]
 open_last_lookups fs/namei.c:3556 [inline]
 path_openat+0x10b8/0x3190 fs/namei.c:3786
 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
 do_sys_open fs/open.c:1434 [inline]
 __do_sys_creat fs/open.c:1512 [inline]
 __se_sys_creat fs/open.c:1506 [inline]
 __x64_sys_creat+0x90/0xb0 fs/open.c:1506
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1154 [inline]
 free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 __slab_free+0x35e/0x410 mm/slub.c:3736
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4420
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049
 new_inode+0x22/0x1b0 fs/inode.c:1075
 __shmem_get_inode mm/shmem.c:2468 [inline]
 shmem_get_inode+0x34f/0xcc0 mm/shmem.c:2540
 shmem_mknod+0x60/0x1d0 mm/shmem.c:3233
 shmem_mkdir+0x33/0x60 mm/shmem.c:3298
 vfs_mkdir+0x296/0x440 fs/namei.c:4113
 do_mkdirat+0x1d4/0x440 fs/namei.c:4136
Modules linked in:
CPU: 0 PID: 5784 Comm: syz-executor Tainted: G    B              syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 bad_page+0x14b/0x170 mm/page_alloc.c:512
 free_page_is_bad mm/page_alloc.c:961 [inline]
 free_pages_prepare mm/page_alloc.c:1146 [inline]
 free_unref_page_prepare+0x887/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 detach_page_private include/linux/pagemap.h:539 [inline]
 erofs_try_to_free_all_cached_pages+0x295/0x600 fs/erofs/zdata.c:657
 erofs_try_to_release_workgroup fs/erofs/utils.c:132 [inline]
 erofs_shrink_workstation+0x118/0x290 fs/erofs/utils.c:161
 erofs_shrinker_unregister+0x5d/0x170 fs/erofs/utils.c:198
 erofs_put_super+0x4e/0x150 fs/erofs/super.c:812
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1660
 erofs_kill_sb+0x4c/0x140 fs/erofs/super.c:794
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f869f9901f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdddd4ae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f869fa11d7d RCX: 00007f869f9901f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdddd4af20
RBP: 00007ffdddd4af20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdddd4bfb0
R13: 00007f869fa11d7d R14: 00000000000243c2 R15: 00007ffdddd4bff0
 </TASK>
BUG: Bad page state in process syz-executor  pfn:2f8ae
page:ffffea0000be2b80 refcount:0 mapcount:0 mapping:ffff888077f027d8 index:0x4 pfn:0x2f8ae
aops:z_erofs_cache_aops ino:0
flags: 0xfff00000000001(locked|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000001 dead000000000100 dead000000000122 ffff888077f027d8
raw: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x192840(GFP_NOWAIT|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6345, tgid 6343 (syz.2.111), ts 148227029870, free_ts 148222203542
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1561 [inline]
 get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
 z_erofs_bind_cache fs/erofs/zdata.c:605 [inline]
 z_erofs_pcluster_begin fs/erofs/zdata.c:889 [inline]
 z_erofs_do_read_page+0x20c0/0x3680 fs/erofs/zdata.c:1024
 z_erofs_pcluster_readmore+0x2cf/0x450 fs/erofs/zdata.c:1833
 z_erofs_read_folio+0x208/0x540 fs/erofs/zdata.c:1853
 filemap_read_folio+0x167/0x760 mm/filemap.c:2420
 do_read_cache_folio+0x470/0x7e0 mm/filemap.c:3789
 erofs_bread+0x16f/0x630 fs/erofs/data.c:48
 erofs_find_target_block fs/erofs/namei.c:103 [inline]
 erofs_namei+0x28c/0xf00 fs/erofs/namei.c:177
 erofs_lookup+0x135/0x310 fs/erofs/namei.c:206
 lookup_open fs/namei.c:3466 [inline]
 open_last_lookups fs/namei.c:3556 [inline]
 path_openat+0x10b8/0x3190 fs/namei.c:3786
 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
 do_sys_open fs/open.c:1434 [inline]
 __do_sys_creat fs/open.c:1512 [inline]
 __se_sys_creat fs/open.c:1506 [inline]
 __x64_sys_creat+0x90/0xb0 fs/open.c:1506
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1154 [inline]
 free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 __slab_free+0x35e/0x410 mm/slub.c:3736
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4420
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049
 new_inode+0x22/0x1b0 fs/inode.c:1075
 __shmem_get_inode mm/shmem.c:2468 [inline]
 shmem_get_inode+0x34f/0xcc0 mm/shmem.c:2540
 shmem_mknod+0x60/0x1d0 mm/shmem.c:3233
 shmem_mkdir+0x33/0x60 mm/shmem.c:3298
 vfs_mkdir+0x296/0x440 fs/namei.c:4113
 do_mkdirat+0x1d4/0x440 fs/namei.c:4136
Modules linked in:
CPU: 0 PID: 5784 Comm: syz-executor Tainted: G    B              syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 bad_page+0x14b/0x170 mm/page_alloc.c:512
 free_page_is_bad mm/page_alloc.c:961 [inline]
 free_pages_prepare mm/page_alloc.c:1146 [inline]
 free_unref_page_prepare+0x887/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 detach_page_private include/linux/pagemap.h:539 [inline]
 erofs_try_to_free_all_cached_pages+0x295/0x600 fs/erofs/zdata.c:657
 erofs_try_to_release_workgroup fs/erofs/utils.c:132 [inline]
 erofs_shrink_workstation+0x118/0x290 fs/erofs/utils.c:161
 erofs_shrinker_unregister+0x5d/0x170 fs/erofs/utils.c:198
 erofs_put_super+0x4e/0x150 fs/erofs/super.c:812
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1660
 erofs_kill_sb+0x4c/0x140 fs/erofs/super.c:794
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f869f9901f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdddd4ae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f869fa11d7d RCX: 00007f869f9901f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdddd4af20
RBP: 00007ffdddd4af20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdddd4bfb0
R13: 00007f869fa11d7d R14: 00000000000243c2 R15: 00007ffdddd4bff0
 </TASK>