loop0: detected capacity change from 0 to 32768
gfs2: Unknown parameter '00000000000000000000003'
loop0: detected capacity change from 0 to 32768
bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=errors=continue,metadata_checksum=none,data_checksum=crc64,compression=lz4,metadata_target=/dev/loop0,noinodes_use_key_cache,very_degraded,nojournal_transaction_names
  allowing incompatible features above 0.0: (unknown version)
bcachefs (loop0): invalid journal entry, version=1.7: mi_btree_bitmap type=btree_keys in superblock: k->u64s 0, fixing
bcachefs (loop0): recovering from clean shutdown, journal seq 13
bcachefs (loop0): Version upgrade required:
Version upgrade from 0.32: (unknown version) to 1.7: mi_btree_bitmap incomplete
Doing incompatible version upgrade from 0.32: (unknown version) to 1.25: extent_flags
  running recovery passes: check_allocations,check_extents_to_backpointers,check_snapshots,check_subvols,check_inodes,check_dirents,set_fs_needs_rebalance
bcachefs (loop0): bcachefs (loop0): error validating btree node on loop0 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
  node offset 8/40 bset u64s 375: checksum error, type chacha20_poly1305_128: got 3d4ab2f9ccd86163284cf28fed2d2e23 should be 61ec379a8789477e76ff1a5280fd6dbd, fixing
==================================================================
BUG: KASAN: use-after-free in poly1305_update include/crypto/poly1305.h:83 [inline]
BUG: KASAN: use-after-free in bch2_checksum+0x238/0x640 fs/bcachefs/checksum.c:157
Read of size 8 at addr ffff8880543b1910 by task syz.0.0/5330

CPU: 0 UID: 0 PID: 5330 Comm: syz.0.0 Not tainted 6.15.0-rc2-syzkaller-00404-g8560697b23dc #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 lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x28f/0x2a0 mm/kasan/generic.c:189
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 poly1305_update include/crypto/poly1305.h:83 [inline]
 bch2_checksum+0x238/0x640 fs/bcachefs/checksum.c:157
 bch2_btree_node_read_done+0x1474/0x6290 fs/bcachefs/btree_io.c:1132
 btree_node_read_work+0x6cb/0x1400 fs/bcachefs/btree_io.c:1366
 bch2_btree_node_read+0x2427/0x29e0 fs/bcachefs/btree_io.c:-1
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1797 [inline]
 bch2_btree_root_read+0x656/0x7e0 fs/bcachefs/btree_io.c:1819
 read_btree_roots+0x3d7/0xa80 fs/bcachefs/recovery.c:581
 bch2_fs_recovery+0x28e4/0x3e20 fs/bcachefs/recovery.c:928
 bch2_fs_start+0x310/0x620 fs/bcachefs/super.c:1065
 bch2_fs_get_tree+0x113e/0x18f0 fs/bcachefs/fs.c:2253
 vfs_get_tree+0x90/0x2b0 fs/super.c:1759
 do_new_mount+0x2cf/0xb70 fs/namespace.c:3881
 do_mount fs/namespace.c:4221 [inline]
 __do_sys_mount fs/namespace.c:4432 [inline]
 __se_sys_mount+0x38c/0x400 fs/namespace.c:4409
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa1cfd8f90a
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:00007fa1d0b73e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fa1d0b73ef0 RCX: 00007fa1cfd8f90a
RDX: 0000200000000000 RSI: 0000200000000080 RDI: 00007fa1d0b73eb0
RBP: 0000200000000000 R08: 00007fa1d0b73ef0 R09: 0000000000000080
R10: 0000000000000080 R11: 0000000000000246 R12: 0000200000000080
R13: 00007fa1d0b73eb0 R14: 000000000000f627 R15: 0000200000000040
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x543b1
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 ffffea000150ec48 ffffea000150ec48 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff8880543b1800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880543b1880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8880543b1900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                         ^
 ffff8880543b1980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880543b1a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================