loop0: detected capacity change from 0 to 32768
bcachefs (/dev/loop0): error reading default superblock: Invalid superblock: too big (got 4760 bytes, layout max 512)
syz.0.0: attempt to access beyond end of device
loop0: rw=6144, sector=18446744073709551615, nr_sectors = 2 limit=32768
bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=metadata_checksum=none,data_checksum=none,compression=lz4,degraded=yes,journal_flush_disabled,fsck,fix_errors=yes,norecovery,nojournal_transaction_names
  allowing incompatible features above 0.0: (unknown version)
  features: lz4,new_siphash,inline_data,new_extent_overwrite,btree_ptr_v2,new_varint,journal_no_flush,alloc_v2,extents_across_btree_nodes
bcachefs (loop0): Using encoding defined by superblock: utf8-12.1.0
bcachefs (loop0): recovering from clean shutdown, journal seq 13
bcachefs (loop0): Doing compatible version upgrade from 1.7: mi_btree_bitmap to 1.28: inode_has_case_insensitive
  running recovery passes: check_allocations,check_extents_to_backpointers,check_inodes
bcachefs (loop0): btree node read error at btree alloc level 0/0
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 1818ce08861e3527 written 40 min_key POS_MIN durability: 1 ptr: 0:26:0 gen 0
  loop0 node offset 0/40 bset u64s 0: checksum error, type chacha20_poly1305_128: got 2b3128554b281fc996daa8c45b178c02 should be a1c0cae4d1c6eac9087fba7ada6f601b
  loop0 node offset 0/40 bset u64s 0: incorrect max key 18446744073709530367:U64_MAX:U32_MAX
  flagging btree alloc lost data
  running recovery pass check_lrus (14), currently at recovery_pass_empty (0)
  running recovery pass check_backpointers_to_extents (16), currently at recovery_pass_empty (0)
  running recovery pass check_alloc_info (13), currently at recovery_pass_empty (0)
  ret btree_node_read_validate_error
bcachefs (loop0): error reading btree root btree=alloc level=0: btree_node_read_error, fixing
bcachefs (loop0): btree node read error at btree snapshots level 0/0
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq d771a06d670df06c written 16 min_key POS_MIN durability: 1 ptr: 0:32:0 gen 0
  loop0 node offset 0/16 bset u64s 0: checksum error, type chacha20_poly1305_128: got 7d32bc923954246f647c1bffb8ad6e4f should be 3f4bb4678363c29f1ca269ce5970cac0
  repair success (rewriting node)
==================================================================
BUG: KASAN: use-after-free in poly1305_update+0x145/0x1b0 lib/crypto/poly1305.c:44
Read of size 8 at addr ffff888052b00090 by task syz.0.0/5327

CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.16.0-rc2-syzkaller-00047-g52da431bf03b #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
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 poly1305_update+0x145/0x1b0 lib/crypto/poly1305.c:44
 bch2_checksum+0x209/0x490 fs/bcachefs/checksum.c:157
 bch2_btree_node_read_done+0x1127/0x51f0 fs/bcachefs/btree_io.c:1155
 btree_node_read_work+0x426/0xe30 fs/bcachefs/btree_io.c:1411
 bch2_btree_node_read+0x887/0x2a00 fs/bcachefs/btree_io.c:-1
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1877 [inline]
 bch2_btree_root_read+0x5f0/0x760 fs/bcachefs/btree_io.c:1899
 read_btree_roots+0x2c2/0x880 fs/bcachefs/recovery.c:604
 bch2_fs_recovery+0x2574/0x3950 fs/bcachefs/recovery.c:979
 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:1804
 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: 0033:0x7f1d0c9900ca
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:00007f1d0d783e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1d0d783ef0 RCX: 00007f1d0c9900ca
RDX: 000020000000f640 RSI: 0000200000000100 RDI: 00007f1d0d783eb0
RBP: 000020000000f640 R08: 00007f1d0d783ef0 R09: 0000000000000180
R10: 0000000000000180 R11: 0000000000000246 R12: 0000200000000100
R13: 00007f1d0d783eb0 R14: 000000000000f646 R15: 0000200000000040
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x52b00
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f0(buddy)
raw: 04fff00000000000 ffff88805ffd7060 ffff88805ffd7060 0000000000000000
raw: 0000000000000000 0000000000000008 00000000f0000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 5, migratetype Reclaimable, gfp_mask 0x4428d0(GFP_NOWAIT|__GFP_RECLAIMABLE|__GFP_IO|__GFP_FS|__GFP_COMP|__GFP_ACCOUNT), pid 5327, tgid 5326 (syz.0.0), ts 85941641895, free_ts 86490435335
 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_noprof+0xa/0x30 mm/page_alloc.c:4993
 __alloc_pages_node_noprof include/linux/gfp.h:284 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:311 [inline]
 ___kmalloc_large_node+0x85/0x210 mm/slub.c:4272
 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4300
 __do_kmalloc_node mm/slub.c:4316 [inline]
 __kvmalloc_node_noprof+0x6d/0x5f0 mm/slub.c:5015
 btree_node_data_alloc+0xdc/0x270 fs/bcachefs/btree_cache.c:150
 __bch2_btree_node_mem_alloc+0x1ef/0x420 fs/bcachefs/btree_cache.c:195
 bch2_fs_btree_cache_init+0x2de/0x690 fs/bcachefs/btree_cache.c:656
 bch2_fs_alloc fs/bcachefs/super.c:999 [inline]
 bch2_fs_open+0x1ceb/0x2570 fs/bcachefs/super.c:2423
 bch2_fs_get_tree+0x437/0x14f0 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x92/0x2b0 fs/super.c:1804
 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
page last free pid 5327 tgid 5326 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_pages_ok+0xa44/0xc20 mm/page_alloc.c:1424
 __folio_put+0x21b/0x2c0 mm/swap.c:112
 folio_put include/linux/mm.h:1356 [inline]
 free_large_kmalloc+0x145/0x200 mm/slub.c:4768
 btree_bounce_free fs/bcachefs/btree_io.c:115 [inline]
 bch2_btree_node_read_done+0x329a/0x51f0 fs/bcachefs/btree_io.c:1294
 btree_node_read_work+0x426/0xe30 fs/bcachefs/btree_io.c:1411
 bch2_btree_node_read+0x887/0x2a00 fs/bcachefs/btree_io.c:-1
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1877 [inline]
 bch2_btree_root_read+0x5f0/0x760 fs/bcachefs/btree_io.c:1899
 read_btree_roots+0x2c2/0x880 fs/bcachefs/recovery.c:604
 bch2_fs_recovery+0x2574/0x3950 fs/bcachefs/recovery.c:979
 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:1804
 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

Memory state around the buggy address:
 ffff888052afff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888052b00000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888052b00080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                         ^
 ffff888052b00100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888052b00180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================