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XFS (loop5): Invalid superblock magic number
XFS (loop6): Invalid superblock magic number
XFS (loop4): Invalid superblock magic number
XFS (loop7): Invalid superblock magic number
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BUG: KASAN: use-after-free in radix_tree_next_chunk+0xf9f/0xfb0 lib/radix-tree.c:1718
Read of size 4 at addr ffff8801d8d92588 by task syz-executor042/8776

CPU: 0 PID: 8776 Comm: syz-executor042 Not tainted 4.17.0-rc5+ #60
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 radix_tree_next_chunk+0xf9f/0xfb0 lib/radix-tree.c:1718
 radix_tree_gang_lookup_tag+0x3d4/0x5f0 lib/radix-tree.c:1916
XFS (loop3): Invalid superblock magic number
 xfs_perag_get_tag+0x12d/0x7c0 fs/xfs/libxfs/xfs_sb.c:88
 xfs_reclaim_inodes_count+0x82/0xb0 fs/xfs/xfs_icache.c:1383
XFS (loop0): Invalid superblock magic number
 xfs_fs_nr_cached_objects+0x37/0x50 fs/xfs/xfs_super.c:1809
 super_cache_count+0x98/0x280 fs/super.c:132
 do_shrink_slab mm/vmscan.c:374 [inline]
 shrink_slab.part.39+0x330/0xf90 mm/vmscan.c:531
 shrink_slab+0xa1/0xc0 mm/vmscan.c:506
 shrink_node+0x4f2/0x1740 mm/vmscan.c:2561
 shrink_zones mm/vmscan.c:2794 [inline]
 do_try_to_free_pages+0x3c9/0x1240 mm/vmscan.c:2856
 try_to_free_mem_cgroup_pages+0x475/0xc50 mm/vmscan.c:3146
 memory_high_write+0x26e/0x2f0 mm/memcontrol.c:5124
 cgroup_file_write+0x317/0x820 kernel/cgroup/cgroup.c:3429
 kernfs_fop_write+0x2ba/0x480 fs/kernfs/file.c:316
 __vfs_write+0x10b/0x960 fs/read_write.c:485
 vfs_write+0x1f8/0x560 fs/read_write.c:549
 ksys_write+0xf9/0x250 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441d29
RSP: 002b:00007ffd74c58c38 EFLAGS: 00000217 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441d29
RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000030
R13: 000000000000a9b8 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 8739:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620
 kmalloc include/linux/slab.h:512 [inline]
 kzalloc include/linux/slab.h:701 [inline]
 xfs_mount_alloc fs/xfs/xfs_super.c:1587 [inline]
 xfs_fs_fill_super+0xda/0x1560 fs/xfs/xfs_super.c:1620
 mount_bdev+0x30c/0x3e0 fs/super.c:1164
 xfs_fs_mount+0x34/0x40 fs/xfs/xfs_super.c:1801
 mount_fs+0xae/0x328 fs/super.c:1267
 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:1027 [inline]
 do_new_mount fs/namespace.c:2518 [inline]
 do_mount+0x564/0x3070 fs/namespace.c:2848
 ksys_mount+0x12d/0x140 fs/namespace.c:3064
 __do_sys_mount fs/namespace.c:3078 [inline]
 __se_sys_mount fs/namespace.c:3075 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8739:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 xfs_fs_fill_super+0x66a/0x1560 fs/xfs/xfs_super.c:1765
 mount_bdev+0x30c/0x3e0 fs/super.c:1164
 xfs_fs_mount+0x34/0x40 fs/xfs/xfs_super.c:1801
 mount_fs+0xae/0x328 fs/super.c:1267
 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:1027 [inline]
 do_new_mount fs/namespace.c:2518 [inline]
 do_mount+0x564/0x3070 fs/namespace.c:2848
 ksys_mount+0x12d/0x140 fs/namespace.c:3064
 __do_sys_mount fs/namespace.c:3078 [inline]
 __se_sys_mount fs/namespace.c:3075 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801d8d92180
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 1032 bytes inside of
 4096-byte region [ffff8801d8d92180, ffff8801d8d93180)
The buggy address belongs to the page:
page:ffffea0007636480 count:1 mapcount:0 mapping:ffff8801d8d92180 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801d8d92180 0000000000000000 0000000100000001
raw: ffffea0006eac020 ffffea0007633c20 ffff8801da800dc0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d8d92480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d8d92500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d8d92580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8801d8d92600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d8d92680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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