==================================================================
BUG: KASAN: slab-use-after-free in bchfs_read+0x2ac0/0x3290 fs/bcachefs/fs-io-buffered.c:228
Read of size 4 at addr ffff888053059a48 by task syz.0.0/5328

CPU: 0 UID: 0 PID: 5328 Comm: syz.0.0 Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #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
 bchfs_read+0x2ac0/0x3290 fs/bcachefs/fs-io-buffered.c:228
 bch2_readahead+0xe7a/0x12d0 fs/bcachefs/fs-io-buffered.c:301
 read_pages+0x193/0x590 mm/readahead.c:160
 page_cache_ra_unbounded+0x708/0x820 mm/readahead.c:297
 do_sync_mmap_readahead+0x3e6/0x6c0 mm/filemap.c:-1
 filemap_fault+0x763/0x13d0 mm/filemap.c:3402
 bch2_page_fault+0x52e/0x960 fs/bcachefs/fs-io-pagecache.c:594
 __do_fault+0x135/0x390 mm/memory.c:5098
 do_shared_fault mm/memory.c:5582 [inline]
 do_fault mm/memory.c:5656 [inline]
 do_pte_missing mm/memory.c:4160 [inline]
 handle_pte_fault+0xfcc/0x61c0 mm/memory.c:5997
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0x1129/0x1bf0 mm/memory.c:6309
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x45b/0x920 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fb208d5690c
Code: 00 00 00 74 a0 83 f9 c0 0f 87 56 fe ff ff 62 e1 fe 28 6f 4e 01 48 29 fe 48 83 c7 3f 49 8d 0c 10 48 83 e7 c0 48 01 fe 48 29 f9 <f3> a4 62 c1 fe 28 7f 00 62 c1 fe 28 7f 48 01 c3 0f 1f 40 00 4c 8b
RSP: 002b:00007fff7c1f6498 EFLAGS: 00010206
RAX: 0000200000025dc0 RBX: 0000000000000004 RCX: 00000000000097f0
RDX: 00000000000097f0 RSI: 00007fb20882ef8f RDI: 0000200000025dc0
RBP: 00007fff7c1f6568 R08: 0000200000025dc0 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000002 R12: 00007fb208fa608c
R13: 00007fb208fa6080 R14: fffffffffffffffe R15: 00007fff7c1f65b0
 </TASK>

Allocated by task 5328:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4151 [inline]
 slab_alloc_node mm/slub.c:4200 [inline]
 kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4207
 mempool_alloc_noprof+0x199/0x5a0 mm/mempool.c:402
 bio_alloc_bioset+0x26f/0x1130 block/bio.c:554
 bch2_readahead+0xbaf/0x12d0 fs/bcachefs/fs-io-buffered.c:290
 read_pages+0x193/0x590 mm/readahead.c:160
 page_cache_ra_unbounded+0x708/0x820 mm/readahead.c:297
 do_sync_mmap_readahead+0x3e6/0x6c0 mm/filemap.c:-1
 filemap_fault+0x763/0x13d0 mm/filemap.c:3402
 bch2_page_fault+0x52e/0x960 fs/bcachefs/fs-io-pagecache.c:594
 __do_fault+0x135/0x390 mm/memory.c:5098
 do_shared_fault mm/memory.c:5582 [inline]
 do_fault mm/memory.c:5656 [inline]
 do_pte_missing mm/memory.c:4160 [inline]
 handle_pte_fault+0xfcc/0x61c0 mm/memory.c:5997
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0x1129/0x1bf0 mm/memory.c:6309
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x45b/0x920 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Freed by task 15:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2389 [inline]
 slab_free_after_rcu_debug+0x11a/0x280 mm/slub.c:4696
 rcu_do_batch kernel/rcu/tree.c:2568 [inline]
 rcu_core+0xaac/0x17a0 kernel/rcu/tree.c:2824
 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579
 run_ksoftirqd+0xcf/0x130 kernel/softirq.c:968
 smpboot_thread_fn+0x576/0xaa0 kernel/smpboot.c:164
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbf/0xd0 mm/kasan/generic.c:548
 slab_free_hook mm/slub.c:2350 [inline]
 slab_free mm/slub.c:4646 [inline]
 kmem_cache_free+0x2ff/0x410 mm/slub.c:4748
 bch2_readpages_end_io+0x17c/0x1d0 fs/bcachefs/fs-io-buffered.c:36
 bch2_rbio_done fs/bcachefs/io_read.c:430 [inline]
 bch2_rbio_retry+0x831/0xd90 fs/bcachefs/io_read.c:537
 bch2_read_io_err+0x442/0x5b0 fs/bcachefs/io_read.c:585
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888053059900
 which belongs to the cache bio-488 of size 488
The buggy address is located 328 bytes inside of
 freed 488-byte region [ffff888053059900, ffff888053059ae8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x53058
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 ffff8880534e8140 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 00000000f5000000 0000000000000000
head: 04fff00000000040 ffff8880534e8140 dead000000000122 0000000000000000
head: 0000000000000000 00000000000c000c 00000000f5000000 0000000000000000
head: 04fff00000000001 ffffea00014c1601 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 0xd2880(GFP_NOWAIT|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5329, tgid 5328 (syz.0.0), ts 76489116495, free_ts 75634339368
 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+0x352b/0x36c0 mm/page_alloc.c:3652
 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2459 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2623
 new_slab mm/slub.c:2676 [inline]
 ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862
 __slab_alloc+0x58/0xa0 mm/slub.c:3952
 __slab_alloc_node mm/slub.c:4027 [inline]
 slab_alloc_node mm/slub.c:4188 [inline]
 kmem_cache_alloc_noprof+0x270/0x390 mm/slub.c:4207
 mempool_alloc_noprof+0x199/0x5a0 mm/mempool.c:402
 bio_alloc_bioset+0x26f/0x1130 block/bio.c:554
 bch2_read_single_folio+0x2cc/0x8a0 fs/bcachefs/fs-io-buffered.c:335
 bch2_read_folio+0x3a/0x70 fs/bcachefs/fs-io-buffered.c:363
 filemap_read_folio+0x14a/0x3b0 mm/filemap.c:2400
 filemap_fault+0xcb9/0x13d0 mm/filemap.c:3494
 bch2_page_fault+0x52e/0x960 fs/bcachefs/fs-io-pagecache.c:594
 __do_fault+0x135/0x390 mm/memory.c:5098
page last free pid 4734 tgid 4734 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2680
 discard_slab mm/slub.c:2720 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3189
 put_cpu_partial+0x17e/0x250 mm/slub.c:3264
 __slab_free+0x294/0x390 mm/slub.c:4516
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4151 [inline]
 slab_alloc_node mm/slub.c:4200 [inline]
 __do_kmalloc_node mm/slub.c:4330 [inline]
 __kmalloc_noprof+0x238/0x4d0 mm/slub.c:4343
 kmalloc_noprof include/linux/slab.h:909 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2be/0x640 security/tomoyo/file.c:822
 security_inode_getattr+0x130/0x330 security/security.c:2377
 vfs_getattr fs/stat.c:243 [inline]
 vfs_fstat fs/stat.c:265 [inline]
 vfs_fstatat+0xa5/0x150 fs/stat.c:366
 __do_sys_newfstatat fs/stat.c:532 [inline]
 __se_sys_newfstatat fs/stat.c:526 [inline]
 __x64_sys_newfstatat+0x11f/0x1a0 fs/stat.c:526
 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

Memory state around the buggy address:
 ffff888053059900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888053059980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888053059a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff888053059a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff888053059b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================