bcachefs (loop0): btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 4a8b0fa43a9980a6 written 24 min_key POS_MIN durability: 1 ptr: 0:37:0 gen 0, fixing
bcachefs (loop0): bucket 0:37 data type btree ptr gen 0 missing in alloc btree
  while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 4a8b0fa43a9980a6 written 24 min_key POS_MIN durability: 1 ptr: 0:37:0 gen 0, fixing
bcachefs (loop0): bucket 0:37 gen 0 different types of data in same bucket: journal, btree
  while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 4a8b0fa43a9980a6 written 24 min_key POS_MIN durability: 1 ptr: 0:37:0 gen 0, fixing
bcachefs (loop0): btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 1db8f60c84bb244c written 8 min_key POS_MIN durability: 1 ptr: 0:42:0 gen 0, fixing
bcachefs (loop0): bucket 0:42 data type btree ptr gen 0 missing in alloc btree
  while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 1db8f60c84bb244c written 8 min_key POS_MIN durability: 1 ptr: 0:42:0 gen 0, fixing
bcachefs (loop0): bucket 0:42 gen 0 different types of data in same bucket: journal, btree
  while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 1db8f60c84bb244c written 8 min_key POS_MIN durability: 1 ptr: 0:42:0 gen 0, fixing
 done
bcachefs (loop0): going read-write
bcachefs (loop0): journal_replay...
bcachefs (loop0): u64s 13 type alloc_v4 0:25:0 len 0 ver 0: 
    gen 0 oldest_gen 0 data_type journal
    journal_seq_nonempty 0
    journal_seq_empty    0
    need_discard         0
    need_inc_gen         0
    dirty_sectors        256
    stripe_sectors       0
    cached_sectors       0
    stripe               0
    stripe_redundancy    0
    io_time[READ]        0
    io_time[WRITE]       0
    fragmentation     0
    bp_start          8
  
  incorrectly set at freespace:0:25:0 (free 0, genbits 0 should be 0), fixing
bcachefs (loop0): u64s 13 type alloc_v4 0:30:0 len 0 ver 0: 
    gen 0 oldest_gen 0 data_type journal
    journal_seq_nonempty 0
    journal_seq_empty    0
    need_discard         0
    need_inc_gen         0
    dirty_sectors        256
    stripe_sectors       0
    cached_sectors       0
    stripe               0
    stripe_redundancy    0
    io_time[READ]        0
    io_time[WRITE]       0
    fragmentation     0
    bp_start          8
  
  incorrectly set at freespace:0:30:0 (free 0, genbits 0 should be 0), fixing
==================================================================
BUG: KASAN: slab-use-after-free in bch2_bucket_alloc_trans+0x1aa0/0x2410 fs/bcachefs/alloc_foreground.c:547
Read of size 8 at addr ffff8880401e1120 by task syz.0.0/5335

CPU: 0 UID: 0 PID: 5335 Comm: syz.0.0 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 bch2_bucket_alloc_trans+0x1aa0/0x2410 fs/bcachefs/alloc_foreground.c:547
 bch2_bucket_alloc_set_trans+0x5a6/0xe70 fs/bcachefs/alloc_foreground.c:728
 __open_bucket_add_buckets+0x1437/0x1e40 fs/bcachefs/alloc_foreground.c:925
 open_bucket_add_buckets+0x2ee/0x440 fs/bcachefs/alloc_foreground.c:957
 bch2_alloc_sectors_start_trans+0xd26/0x1e80 fs/bcachefs/alloc_foreground.c:-1
 __bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:320 [inline]
 bch2_btree_reserve_get+0x641/0x1810 fs/bcachefs/btree_update_interior.c:534
 bch2_btree_update_start+0x147e/0x1dc0 fs/bcachefs/btree_update_interior.c:1270
 bch2_btree_split_leaf+0x14b/0x8e0 fs/bcachefs/btree_update_interior.c:1920
 bch2_trans_commit_error+0x1b7/0x1130 fs/bcachefs/btree_trans_commit.c:911
 __bch2_trans_commit+0x1ce8/0x8880 fs/bcachefs/btree_trans_commit.c:1098
 bch2_trans_commit fs/bcachefs/btree_update.h:242 [inline]
 bch2_journal_replay+0x1789/0x2620 fs/bcachefs/recovery.c:396
 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:485 [inline]
 __bch2_run_recovery_passes+0x395/0x1010 fs/bcachefs/recovery_passes.c:540
 bch2_run_recovery_passes+0x184/0x210 fs/bcachefs/recovery_passes.c:611
 bch2_fs_recovery+0x25fd/0x3950 fs/bcachefs/recovery.c:989
 bch2_fs_start+0xa99/0xd90 fs/bcachefs/super.c:1203
 bch2_fs_get_tree+0xb02/0x14f0 fs/bcachefs/fs.c:2489
 vfs_get_tree+0x92/0x2b0 fs/super.c:1802
 do_new_mount+0x24a/0xa40 fs/namespace.c:3885
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd2425900ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd23e9f4e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fd23e9f4ef0 RCX: 00007fd2425900ca
RDX: 0000200000000000 RSI: 0000200000000080 RDI: 00007fd23e9f4eb0
RBP: 0000200000000000 R08: 00007fd23e9f4ef0 R09: 0000000000818001
R10: 0000000000818001 R11: 0000000000000246 R12: 0000200000000080
R13: 00007fd23e9f4eb0 R14: 000000000000596b R15: 00002000000003c0
 </TASK>

Allocated by task 5335:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x124/0x340 mm/slub.c:4958
 __bch2_trans_kmalloc+0x26c/0xc80 fs/bcachefs/btree_iter.c:3187
 bch2_trans_kmalloc_nomemzero_ip fs/bcachefs/btree_iter.h:586 [inline]
 bch2_trans_kmalloc_nomemzero fs/bcachefs/btree_iter.h:621 [inline]
 bch2_alloc_sectors_start_trans+0x1d59/0x1e80 fs/bcachefs/alloc_foreground.c:1250
 __bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:320 [inline]
 bch2_btree_reserve_get+0x641/0x1810 fs/bcachefs/btree_update_interior.c:534
 bch2_btree_update_start+0x147e/0x1dc0 fs/bcachefs/btree_update_interior.c:1270
 bch2_btree_split_leaf+0x14b/0x8e0 fs/bcachefs/btree_update_interior.c:1920
 bch2_trans_commit_error+0x1b7/0x1130 fs/bcachefs/btree_trans_commit.c:911
 __bch2_trans_commit+0x1ce8/0x8880 fs/bcachefs/btree_trans_commit.c:1098
 bch2_trans_commit fs/bcachefs/btree_update.h:242 [inline]
 bch2_journal_replay+0x1789/0x2620 fs/bcachefs/recovery.c:396
 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:485 [inline]
 __bch2_run_recovery_passes+0x395/0x1010 fs/bcachefs/recovery_passes.c:540
 bch2_run_recovery_passes+0x184/0x210 fs/bcachefs/recovery_passes.c:611
 bch2_fs_recovery+0x25fd/0x3950 fs/bcachefs/recovery.c:989
 bch2_fs_start+0xa99/0xd90 fs/bcachefs/super.c:1203
 bch2_fs_get_tree+0xb02/0x14f0 fs/bcachefs/fs.c:2489
 vfs_get_tree+0x92/0x2b0 fs/super.c:1802
 do_new_mount+0x24a/0xa40 fs/namespace.c:3885
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5335:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 krealloc_noprof+0x1cd/0x340 mm/slub.c:-1
 __bch2_trans_kmalloc+0x26c/0xc80 fs/bcachefs/btree_iter.c:3187
 bch2_trans_kmalloc_nomemzero_ip fs/bcachefs/btree_iter.h:586 [inline]
 bch2_trans_kmalloc_nomemzero fs/bcachefs/btree_iter.h:621 [inline]
 __bch2_trans_subbuf_alloc+0x2da/0x460 fs/bcachefs/btree_update.c:557
 bch2_trans_subbuf_alloc fs/bcachefs/btree_update.h:148 [inline]
 bch2_trans_jset_entry_alloc fs/bcachefs/btree_update.h:168 [inline]
 __bch2_trans_log_str fs/bcachefs/btree_update.c:814 [inline]
 bch2_trans_log_str+0xd5/0x3c0 fs/bcachefs/btree_update.c:827
 __bch2_fsck_err+0xc11/0xfb0 fs/bcachefs/error.c:625
 bch2_check_discard_freespace_key+0x71b/0xce0 fs/bcachefs/alloc_background.c:1436
 try_alloc_bucket fs/bcachefs/alloc_foreground.c:272 [inline]
 bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:420 [inline]
 bch2_bucket_alloc_trans+0x1333/0x2410 fs/bcachefs/alloc_foreground.c:544
 bch2_bucket_alloc_set_trans+0x5a6/0xe70 fs/bcachefs/alloc_foreground.c:728
 __open_bucket_add_buckets+0x1437/0x1e40 fs/bcachefs/alloc_foreground.c:925
 open_bucket_add_buckets+0x2ee/0x440 fs/bcachefs/alloc_foreground.c:957
 bch2_alloc_sectors_start_trans+0xd26/0x1e80 fs/bcachefs/alloc_foreground.c:-1
 __bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:320 [inline]
 bch2_btree_reserve_get+0x641/0x1810 fs/bcachefs/btree_update_interior.c:534
 bch2_btree_update_start+0x147e/0x1dc0 fs/bcachefs/btree_update_interior.c:1270
 bch2_btree_split_leaf+0x14b/0x8e0 fs/bcachefs/btree_update_interior.c:1920
 bch2_trans_commit_error+0x1b7/0x1130 fs/bcachefs/btree_trans_commit.c:911
 __bch2_trans_commit+0x1ce8/0x8880 fs/bcachefs/btree_trans_commit.c:1098
 bch2_trans_commit fs/bcachefs/btree_update.h:242 [inline]
 bch2_journal_replay+0x1789/0x2620 fs/bcachefs/recovery.c:396
 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:485 [inline]
 __bch2_run_recovery_passes+0x395/0x1010 fs/bcachefs/recovery_passes.c:540
 bch2_run_recovery_passes+0x184/0x210 fs/bcachefs/recovery_passes.c:611
 bch2_fs_recovery+0x25fd/0x3950 fs/bcachefs/recovery.c:989
 bch2_fs_start+0xa99/0xd90 fs/bcachefs/super.c:1203
 bch2_fs_get_tree+0xb02/0x14f0 fs/bcachefs/fs.c:2489
 vfs_get_tree+0x92/0x2b0 fs/super.c:1802
 do_new_mount+0x24a/0xa40 fs/namespace.c:3885
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880401e1000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 288 bytes inside of
 freed 512-byte region [ffff8880401e1000, ffff8880401e1200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x401e0
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000040 ffff88801a441c80 ffffea0001008100 0000000000000002
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 04fff00000000040 ffff88801a441c80 ffffea0001008100 0000000000000002
head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 04fff00000000001 ffffea0001007801 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10, tgid 10 (kworker/0:1), ts 80227850657, free_ts 66200899372
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 drm_atomic_helper_setup_commit+0x1c9/0x1370 drivers/gpu/drm/drm_atomic_helper.c:2326
 drm_atomic_helper_commit+0x6a/0xb10 drivers/gpu/drm/drm_atomic_helper.c:2061
 drm_atomic_commit+0x25f/0x2c0 drivers/gpu/drm/drm_atomic.c:1577
 drm_atomic_helper_dirtyfb+0xd7b/0xee0 drivers/gpu/drm/drm_damage_helper.c:181
 drm_fbdev_shmem_helper_fb_dirty+0x160/0x2f0 drivers/gpu/drm/drm_fbdev_shmem.c:117
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:379 [inline]
 drm_fb_helper_damage_work+0x221/0x710 drivers/gpu/drm/drm_fb_helper.c:402
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
page last free pid 5229 tgid 5229 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3186
 put_cpu_partial+0x17c/0x250 mm/slub.c:3261
 __slab_free+0x2f7/0x400 mm/slub.c:4513
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204
 vm_area_alloc+0x24/0x140 mm/vma_init.c:31
 __install_special_mapping mm/mmap.c:1453 [inline]
 _install_special_mapping+0x2e/0x350 mm/mmap.c:1501
 map_vdso+0x1df/0x480 arch/x86/entry/vdso/vma.c:159
 load_elf_binary+0x1bd9/0x2790 fs/binfmt_elf.c:1276
 search_binary_handler fs/exec.c:1665 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve+0x99c/0x1450 fs/exec.c:1749
 do_execveat_common+0x510/0x6a0 fs/exec.c:1855
 do_execve fs/exec.c:1929 [inline]
 __do_sys_execve fs/exec.c:2005 [inline]
 __se_sys_execve fs/exec.c:2000 [inline]
 __x64_sys_execve+0x94/0xb0 fs/exec.c:2000
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94

Memory state around the buggy address:
 ffff8880401e1000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880401e1080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880401e1100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff8880401e1180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880401e1200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================