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=none,compression=lz4,nocow 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): initializing new filesystem bcachefs (loop0): going read-write bcachefs (loop0): marking superblocks bcachefs (loop0): initializing freespace bcachefs (loop0): done initializing freespace bcachefs (loop0): reading snapshots table bcachefs (loop0): reading snapshots done bcachefs (loop0): done starting filesystem loop0: detected capacity change from 32768 to 64 syz.0.0: attempt to access beyond end of device loop0: rw=2049, sector=6400, nr_sectors = 8 limit=64 bcachefs (loop0 inum 4098 offset 0): data write error: I/O ================================================================== BUG: KASAN: slab-use-after-free in __bch2_write+0x38f8/0x3900 fs/bcachefs/io_write.c:1506 Read of size 2 at addr ffff8880531d937c by task syz.0.0/5368 CPU: 0 UID: 0 PID: 5368 Comm: syz.0.0 Not tainted syzkaller #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: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __bch2_write+0x38f8/0x3900 fs/bcachefs/io_write.c:1506 closure_queue include/linux/closure.h:270 [inline] closure_call include/linux/closure.h:432 [inline] bch2_writepage_do_io fs/bcachefs/fs-io-buffered.c:486 [inline] bch2_writepages+0x211/0x2d0 fs/bcachefs/fs-io-buffered.c:668 do_writepages+0x32b/0x550 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] filemap_write_and_wait_range+0x21f/0x320 mm/filemap.c:691 bch2_write_invalidate_inode_pages_range+0x7c/0x110 fs/bcachefs/fs-io-pagecache.c:61 bchfs_fcollapse_finsert+0x1f2/0x470 fs/bcachefs/fs-io.c:614 bch2_fallocate_dispatch+0x2a4/0x410 fs/bcachefs/fs-io.c:-1 vfs_fallocate+0x666/0x7e0 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:369 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: 0033:0x7f46d678ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f46d752b038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f46d69b5fa0 RCX: 00007f46d678ebe9 RDX: 0000000000000000 RSI: 0000000000000020 RDI: 0000000000000006 RBP: 00007f46d6811e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000010000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f46d69b6038 R14: 00007f46d69b5fa0 R15: 00007ffc5a47df98 Allocated by task 5368: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 mempool_alloc_noprof+0x1a4/0x510 mm/mempool.c:406 bio_alloc_bioset+0x241/0x1110 block/bio.c:555 bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:502 [inline] __bch2_writepage+0x1581/0x2790 fs/bcachefs/fs-io-buffered.c:636 write_cache_pages+0x61/0x100 mm/page-writeback.c:2612 bch2_writepages+0xf9/0x2d0 fs/bcachefs/fs-io-buffered.c:666 do_writepages+0x32b/0x550 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] filemap_write_and_wait_range+0x21f/0x320 mm/filemap.c:691 bch2_write_invalidate_inode_pages_range+0x7c/0x110 fs/bcachefs/fs-io-pagecache.c:61 bchfs_fcollapse_finsert+0x1f2/0x470 fs/bcachefs/fs-io.c:614 bch2_fallocate_dispatch+0x2a4/0x410 fs/bcachefs/fs-io.c:-1 vfs_fallocate+0x666/0x7e0 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:369 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 Freed by task 15: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free_after_rcu_debug+0x129/0x2a0 mm/slub.c:4730 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x283/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 slab_free_hook mm/slub.c:2378 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x2f6/0x400 mm/slub.c:4782 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2184 __queue_work+0xcd2/0xfb0 kernel/workqueue.c:2339 queue_work_on+0x181/0x270 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:669 [inline] closure_queue include/linux/closure.h:268 [inline] closure_put_after_sub+0x2ac/0x320 lib/closure.c:42 bch2_nocow_write+0x3ab2/0x3e90 fs/bcachefs/io_write.c:1462 __bch2_write+0x371c/0x3900 fs/bcachefs/io_write.c:1505 closure_queue include/linux/closure.h:270 [inline] closure_call include/linux/closure.h:432 [inline] bch2_writepage_do_io fs/bcachefs/fs-io-buffered.c:486 [inline] bch2_writepages+0x211/0x2d0 fs/bcachefs/fs-io-buffered.c:668 do_writepages+0x32b/0x550 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] filemap_write_and_wait_range+0x21f/0x320 mm/filemap.c:691 bch2_write_invalidate_inode_pages_range+0x7c/0x110 fs/bcachefs/fs-io-pagecache.c:61 bchfs_fcollapse_finsert+0x1f2/0x470 fs/bcachefs/fs-io.c:614 bch2_fallocate_dispatch+0x2a4/0x410 fs/bcachefs/fs-io.c:-1 vfs_fallocate+0x666/0x7e0 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:369 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 The buggy address belongs to the object at ffff8880531d9300 which belongs to the cache bio-1072 of size 1072 The buggy address is located 124 bytes inside of freed 1072-byte region [ffff8880531d9300, ffff8880531d9730) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x531d8 head: order:2 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 ffff888043425500 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff888043425500 dead000000000122 0000000000000000 head: 0000000000000000 00000000800d000d 00000000f5000000 0000000000000000 head: 04fff00000000002 ffffea00014c7601 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5368, tgid 5366 (syz.0.0), ts 86205037094, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236 mempool_init_node+0x1e7/0x4d0 mm/mempool.c:221 mempool_init_noprof+0x3a/0x50 mm/mempool.c:250 bioset_init+0x2eb/0x790 block/bio.c:1809 bch2_fs_fs_io_buffered_init+0x2b/0x50 fs/bcachefs/fs-io-buffered.c:1101 bch2_fs_init_rw+0x246/0x2d0 fs/bcachefs/super.c:815 bch2_fs_alloc fs/bcachefs/super.c:1022 [inline] bch2_fs_open+0x2338/0x2600 fs/bcachefs/super.c:2433 bch2_fs_get_tree+0x44f/0x1520 fs/bcachefs/fs.c:2472 vfs_get_tree+0x92/0x2b0 fs/super.c:1815 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808 page_owner free stack trace missing Memory state around the buggy address: ffff8880531d9200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff8880531d9280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880531d9300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880531d9380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880531d9400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================