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BUG: KASAN: use-after-free in dtMoveEntry fs/jfs/jfs_dtree.c:3934 [inline]
BUG: KASAN: use-after-free in dtSplitPage+0x1e37/0x3b20 fs/jfs/jfs_dtree.c:1561
Write of size 1 at addr ffff88805337a000 by task syz.0.0/5370

CPU: 0 UID: 0 PID: 5370 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:
 <TASK>
 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
 dtMoveEntry fs/jfs/jfs_dtree.c:3934 [inline]
 dtSplitPage+0x1e37/0x3b20 fs/jfs/jfs_dtree.c:1561
 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
 dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_rename+0x7bc/0x1610 fs/jfs/namei.c:1225
 vfs_rename+0xbd7/0xf00 fs/namei.c:5129
 do_renameat2+0x6ce/0xa80 fs/namei.c:5278
 __do_sys_rename fs/namei.c:5325 [inline]
 __se_sys_rename fs/namei.c:5323 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5323
 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: 0033:0x7ff0ced8eec9
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:00007ff0cfbfa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007ff0cefe6180 RCX: 00007ff0ced8eec9
RDX: 0000000000000000 RSI: 0000200000000f40 RDI: 0000200000000300
RBP: 00007ff0cee11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0cefe6218 R14: 00007ff0cefe6180 R15: 00007ffd1e45c018
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5337a
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 ffffea00014cdec8 ffff88801fc3fea0 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff888053379f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888053379f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805337a000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88805337a080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805337a100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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