bcachefs (loop9): starting version 1.7: mi_btree_bitmap opts=metadata_checksum=none,data_checksum=none,compression=lz4,background_compression=lz4,nojournal_transaction_names,version_upgrade=none
bcachefs (loop9): recovering from clean shutdown, journal seq 13
==================================================================
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 ffff88805912c690 by task syz.9.302/8384

CPU: 1 UID: 0 PID: 8384 Comm: syz.9.302 Not tainted 6.15.0-rc2-syzkaller-00048-gc62f4b82d571 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:1059
 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+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1ed758f90a
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:00007f1ed83cbe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1ed83cbef0 RCX: 00007f1ed758f90a
RDX: 0000200000000080 RSI: 000020000000f680 RDI: 00007f1ed83cbeb0
RBP: 0000200000000080 R08: 00007f1ed83cbef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000020000000f680
R13: 00007f1ed83cbeb0 R14: 000000000000f629 R15: 0000200000000000
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5912c
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 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 0x452cd0(GFP_KERNEL_ACCOUNT|__GFP_RECLAIMABLE|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 8384, tgid 8383 (syz.9.302), ts 247810561680, free_ts 248132183006
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717
 prep_new_page mm/page_alloc.c:1725 [inline]
 get_page_from_freelist+0x351d/0x36b0 mm/page_alloc.c:3652
 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934
 __alloc_pages_noprof+0xa/0x30 mm/page_alloc.c:4968
 __alloc_pages_node_noprof include/linux/gfp.h:284 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:311 [inline]
 ___kmalloc_large_node+0x92/0x210 mm/slub.c:4275
 __kmalloc_large_node_noprof+0x1a/0x80 mm/slub.c:4303
 __do_kmalloc_node mm/slub.c:4319 [inline]
 __kvmalloc_node_noprof+0x7c/0x5a0 mm/slub.c:5016
 btree_node_data_alloc+0xdb/0x260 fs/bcachefs/btree_cache.c:156
 __bch2_btree_node_mem_alloc+0x201/0x420 fs/bcachefs/btree_cache.c:201
 bch2_fs_btree_cache_init+0x27a/0x630 fs/bcachefs/btree_cache.c:656
 bch2_fs_alloc fs/bcachefs/super.c:942 [inline]
 bch2_fs_open+0x2dea/0x32a0 fs/bcachefs/super.c:2209
 bch2_fs_get_tree+0x77b/0x18f0 fs/bcachefs/fs.c:2172
 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+0xf3/0x230 arch/x86/entry/syscall_64.c:94
page last free pid 8384 tgid 8383 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_pages_ok+0xb17/0xd90 mm/page_alloc.c:1437
 __folio_put+0x2b5/0x360 mm/swap.c:112
 folio_put include/linux/mm.h:1563 [inline]
 free_large_kmalloc+0x143/0x1e0 mm/slub.c:4771
 kfree+0x216/0x430 mm/slub.c:4839
 btree_bounce_free fs/bcachefs/btree_io.c:112 [inline]
 bch2_btree_node_read_done+0x3da2/0x6290 fs/bcachefs/btree_io.c:1245
 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:1059
 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+0xf3/0x230 arch/x86/entry/syscall_64.c:94

Memory state around the buggy address:
 ffff88805912c580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805912c600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88805912c680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                         ^
 ffff88805912c700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805912c780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================