BTRFS info (device loop4): disabling disk space caching
BTRFS info (device loop4): setting 16 feature flag
BTRFS info (device loop4): force zstd compression, level 0
==================================================================
BUG: KASAN: use-after-free in isofs_read_inode fs/isofs/inode.c:1354 [inline]
BUG: KASAN: use-after-free in __isofs_iget+0x1b18/0x2000 fs/isofs/inode.c:1554
Read of size 1 at addr ffff88804f164018 by task syz-executor.3/12251

CPU: 1 PID: 12251 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0
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+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
BTRFS info (device loop4): has skinny extents
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430
 isofs_read_inode fs/isofs/inode.c:1354 [inline]
 __isofs_iget+0x1b18/0x2000 fs/isofs/inode.c:1554
 isofs_iget fs/isofs/isofs.h:133 [inline]
 isofs_export_iget fs/isofs/export.c:29 [inline]
 isofs_export_iget fs/isofs/export.c:20 [inline]
 isofs_fh_to_dentry fs/isofs/export.c:170 [inline]
 isofs_fh_to_dentry+0x117/0x1f0 fs/isofs/export.c:162
 exportfs_decode_fh+0x126/0x7e0 fs/exportfs/expfs.c:433
 do_handle_to_path fs/fhandle.c:152 [inline]
 handle_to_path fs/fhandle.c:207 [inline]
 do_handle_open+0x2f4/0x650 fs/fhandle.c:223
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3fd73ba049
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3fd5d0e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000130
RAX: ffffffffffffffda RBX: 00007f3fd74cd030 RCX: 00007f3fd73ba049
RDX: 5091cf25ccb38898 RSI: 0000000020000040 RDI: 0000000000000013
RBP: 00007f3fd741408d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc1df3195f R14: 00007f3fd5d0e300 R15: 0000000000022000

The buggy address belongs to the page:
page:ffffea00013c5900 count:0 mapcount:-128 mapping:0000000000000000 index:0x1
flags: 0xfff00000000000()
raw: 00fff00000000000 ffffea00011d8008 ffffea00011d1308 0000000000000000
raw: 0000000000000001 0000000000000002 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804f163f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804f163f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804f164000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff88804f164080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804f164100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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