==================================================================
BUG: KASAN: slab-use-after-free in xfs_defer_item_unpause+0x116/0x250 fs/xfs/libxfs/xfs_defer.c:1242
Read of size 4 at addr ffff888042eb769c by task syz.0.0/5335

CPU: 0 UID: 0 PID: 5335 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 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 xfs_defer_item_unpause+0x116/0x250 fs/xfs/libxfs/xfs_defer.c:1242
 xrep_newbt_free+0x3fe/0x5f0 fs/xfs/scrub/newbt.c:520
 xrep_rmap_build_new_tree+0x5b5/0x8c0 fs/xfs/scrub/rmap_repair.c:1447
 xrep_rmapbt+0x78/0xb0 fs/xfs/scrub/rmap_repair.c:1722
 xrep_attempt+0x184/0x7c0 fs/xfs/scrub/repair.c:78
 xfs_scrub_metadata+0xce4/0x1910 fs/xfs/scrub/scrub.c:747
 xfs_ioc_scrubv_metadata+0x7ac/0xb70 fs/xfs/scrub/scrub.c:981
 xfs_file_ioctl+0x916/0x1590 fs/xfs/xfs_ioctl.c:1308
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff28619e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff286fd2fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff286426180 RCX: 00007ff28619e159
RDX: 0000200000000000 RSI: 00000000c0285840 RDI: 0000000000000008
RBP: 00007ff286235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff286426218 R14: 00007ff286426180 R15: 00007ffe33b529e8
 </TASK>

Allocated by task 5335:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 kmem_cache_alloc_noprof+0x2b9/0x600 mm/slub.c:5010
 xfs_defer_alloc fs/xfs/libxfs/xfs_defer.c:829 [inline]
 xfs_defer_add+0x143/0x480 fs/xfs/libxfs/xfs_defer.c:857
 xfs_extent_free_defer_add+0x1bf/0x3b0 fs/xfs/xfs_extfree_item.c:507
 xfs_defer_extent_free+0x2a8/0x400 fs/xfs/libxfs/xfs_alloc.c:2682
 xfs_alloc_schedule_autoreap+0xb0/0x170 fs/xfs/libxfs/xfs_alloc.c:2727
 xrep_newbt_add_blocks+0x239/0x410 fs/xfs/scrub/newbt.c:209
 xrep_newbt_alloc_ag_blocks+0x81e/0xcc0 fs/xfs/scrub/newbt.c:309
 xrep_rmap_try_reserve+0x1f4/0x800 fs/xfs/scrub/rmap_repair.c:1068
 xrep_rmap_reserve_space+0x19a/0x470 fs/xfs/scrub/rmap_repair.c:1162
 xrep_rmap_build_new_tree+0x3d9/0x8c0 fs/xfs/scrub/rmap_repair.c:1369
 xrep_rmapbt+0x78/0xb0 fs/xfs/scrub/rmap_repair.c:1722
 xrep_attempt+0x184/0x7c0 fs/xfs/scrub/repair.c:78
 xfs_scrub_metadata+0xce4/0x1910 fs/xfs/scrub/scrub.c:747
 xfs_ioc_scrubv_metadata+0x7ac/0xb70 fs/xfs/scrub/scrub.c:981
 xfs_file_ioctl+0x916/0x1590 fs/xfs/xfs_ioctl.c:1308
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5335:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kmem_cache_free+0x182/0x650 mm/slub.c:6626
 xfs_defer_cancel_list fs/xfs/libxfs/xfs_defer.c:504 [inline]
 xfs_defer_finish_noroll+0xde4/0x1320 fs/xfs/libxfs/xfs_defer.c:723
 xfs_defer_finish+0x1c/0x180 fs/xfs/libxfs/xfs_defer.c:741
 xrep_defer_finish+0x16e/0x240 fs/xfs/scrub/repair.c:242
 xfs_btree_bload_prep_block+0x36e/0x6d0 fs/xfs/libxfs/xfs_btree_staging.c:321
 xfs_btree_bload+0x29e/0xf60 fs/xfs/libxfs/xfs_btree_staging.c:716
 xrep_rmap_build_new_tree+0x542/0x8c0 fs/xfs/scrub/rmap_repair.c:1401
 xrep_rmapbt+0x78/0xb0 fs/xfs/scrub/rmap_repair.c:1722
 xrep_attempt+0x184/0x7c0 fs/xfs/scrub/repair.c:78
 xfs_scrub_metadata+0xce4/0x1910 fs/xfs/scrub/scrub.c:747
 xfs_ioc_scrubv_metadata+0x7ac/0xb70 fs/xfs/scrub/scrub.c:981
 xfs_file_ioctl+0x916/0x1590 fs/xfs/xfs_ioctl.c:1308
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888042eb7660
 which belongs to the cache xfs_defer_pending of size 64
The buggy address is located 60 bytes inside of
 freed 64-byte region [ffff888042eb7660, ffff888042eb76a0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x42eb7
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff88803243ec80 dead000000000122 0000000000000000
raw: 0000000000000000 00000002002a002a 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5319, tgid 5317 (syz.0.0), ts 96470143567
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab+0x7d/0x620 mm/slub.c:3462
 new_slab mm/slub.c:3513 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 kmem_cache_alloc_noprof+0x399/0x600 mm/slub.c:5010
 xfs_defer_alloc fs/xfs/libxfs/xfs_defer.c:829 [inline]
 xfs_defer_add+0x143/0x480 fs/xfs/libxfs/xfs_defer.c:857
 xfs_bmap_add_extent_hole_real+0xd61/0x1a40 fs/xfs/libxfs/xfs_bmap.c:2782
 xfs_bmapi_allocate+0x248c/0x2f20 fs/xfs/libxfs/xfs_bmap.c:3975
 xfs_bmapi_write+0x843/0x1330 fs/xfs/libxfs/xfs_bmap.c:4265
 xfs_iomap_write_direct+0x3a3/0x6a0 fs/xfs/xfs_iomap.c:338
 xfs_direct_write_iomap_begin+0x100a/0x1450 fs/xfs/xfs_iomap.c:1012
 iomap_iter_next include/linux/iomap.h:382 [inline]
 xfs_direct_write_iomap_next+0xfd/0x150 fs/xfs/xfs_iomap.c:1040
 iomap_iter+0xe2/0xec0 fs/iomap/iter.c:122
 __iomap_dio_rw+0xc87/0x1c40 fs/iomap/direct-io.c:815
page last free pid 5318 tgid 5317 ts 96410685952 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962
 __slab_free+0x274/0x2c0 mm/slub.c:5815
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 __do_kmalloc_node mm/slub.c:5413 [inline]
 __kmalloc_noprof+0x307/0x720 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 copy_splice_read+0x16f/0xaa0 fs/splice.c:336
 do_splice_read fs/splice.c:979 [inline]
 splice_direct_to_actor+0x4b6/0xcb0 fs/splice.c:1084
 do_splice_direct_actor fs/splice.c:1202 [inline]
 do_splice_direct+0x195/0x290 fs/splice.c:1228
 do_sendfile+0x52e/0x7c0 fs/read_write.c:1371
 __do_sys_sendfile64 fs/read_write.c:1432 [inline]
 __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1418
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888042eb7580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888042eb7600: fa fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb
>ffff888042eb7680: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fb
                            ^
 ffff888042eb7700: fc fc fc fc fa fb fb fb fb fb fb fb fc fc fc fc
 ffff888042eb7780: fa fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb
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