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BUG: KASAN: slab-out-of-bounds in poly1305_update_arch+0x259/0x7d0 arch/x86/crypto/poly1305_glue.c:198
Read of size 8 at addr ffff888065ac18e0 by task syz-executor.0/7076

CPU: 1 PID: 7076 Comm: syz-executor.0 Not tainted 6.10.0-rc2-syzkaller-00366-g771ed66105de #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 poly1305_update_arch+0x259/0x7d0 arch/x86/crypto/poly1305_glue.c:198
 crypto_poly1305_update+0x28/0x40 arch/x86/crypto/poly1305_glue.c:230
 bch2_checksum+0x5e9/0x770 fs/bcachefs/checksum.c:229
 bch2_btree_node_read_done+0x13de/0x6750 fs/bcachefs/btree_io.c:1115
 btree_node_read_work+0x68b/0x1260 fs/bcachefs/btree_io.c:1345
 bch2_btree_node_read+0x2433/0x2a10
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1769 [inline]
 bch2_btree_root_read+0x61e/0x970 fs/bcachefs/btree_io.c:1793
 read_btree_roots+0x22d/0x7b0 fs/bcachefs/recovery.c:475
 bch2_fs_recovery+0x2346/0x3720 fs/bcachefs/recovery.c:803
 bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1031
 bch2_fs_open+0xa8d/0xdf0 fs/bcachefs/super.c:2123
 bch2_mount+0x6c0/0x1320 fs/bcachefs/fs.c:1917
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2a0 fs/super.c:1780
 do_new_mount+0x2be/0xb40 fs/namespace.c:3352
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffb7027e66a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffb71028ef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffb71028f80 RCX: 00007ffb7027e66a
RDX: 0000000020011a00 RSI: 0000000020011a40 RDI: 00007ffb71028f40
RBP: 0000000020011a00 R08: 00007ffb71028f80 R09: 0000000001200014
R10: 0000000001200014 R11: 0000000000000202 R12: 0000000020011a40
R13: 00007ffb71028f40 R14: 00000000000119f9 R15: 0000000020000100
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x65a80
head: order:7 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff00000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff00000000007 ffffea000196a001 ffffffffffffffff 0000000000000000
head: 0000000000000080 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 7, migratetype Unmovable, gfp_mask 0x152cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 7076, tgid 7073 (syz-executor.0), ts 181111110826, free_ts 180464325532
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x2e43/0x2f00 mm/page_alloc.c:3420
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4678
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 __kmalloc_large_node+0x8b/0x1d0 mm/slub.c:4067
 __do_kmalloc_node mm/slub.c:4110 [inline]
 __kmalloc_node_noprof+0x2d2/0x440 mm/slub.c:4129
 kmalloc_node_noprof include/linux/slab.h:681 [inline]
 kvmalloc_node_noprof+0x72/0x190 mm/util.c:634
 mempool_init_node+0x1ee/0x4e0 mm/mempool.c:217
 mempool_init_noprof+0x3a/0x50 mm/mempool.c:246
 mempool_init_kvmalloc_pool include/linux/mempool.h:105 [inline]
 __bch2_fs_compress_init+0x60e/0x9a0 fs/bcachefs/compress.c:625
 bch2_fs_alloc+0x1db1/0x2030 fs/bcachefs/super.c:922
 bch2_fs_open+0x8cc/0xdf0 fs/bcachefs/super.c:2102
 bch2_mount+0x6c0/0x1320 fs/bcachefs/fs.c:1917
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2a0 fs/super.c:1780
 do_new_mount+0x2be/0xb40 fs/namespace.c:3352
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
page last free pid 6779 tgid 6779 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 __free_pages_ok+0xb46/0xcb0 mm/page_alloc.c:1208
 __folio_put+0x3b9/0x620 mm/swap.c:129
 folio_put include/linux/mm.h:1508 [inline]
 free_large_kmalloc+0x105/0x1c0 mm/slub.c:4529
 kfree+0x1c4/0x360 mm/slub.c:4552
 mempool_exit+0xc7/0x1a0 mm/mempool.c:170
 bch2_fs_compress_exit+0x4b/0x90 fs/bcachefs/compress.c:564
 __bch2_fs_free fs/bcachefs/super.c:561 [inline]
 bch2_fs_release+0x23b/0x720 fs/bcachefs/super.c:603
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1267
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888065ac1780: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff888065ac1800: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
>ffff888065ac1880: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                                       ^
 ffff888065ac1900: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff888065ac1980: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
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