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BUG: KASAN: use-after-free in __rb_insert lib/rbtree.c:115 [inline]
BUG: KASAN: use-after-free in __rb_insert_augmented+0xa0/0x610 lib/rbtree.c:459
Read of size 8 at addr ffff8881c0000008 by task syz-executor/4565

CPU: 0 PID: 4565 Comm: syz-executor Tainted: G        W         5.15.151-syzkaller-00059-g5356d2f17edf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 print_address_description+0x87/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:444
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 __rb_insert lib/rbtree.c:115 [inline]
 __rb_insert_augmented+0xa0/0x610 lib/rbtree.c:459
 rb_insert_augmented include/linux/rbtree_augmented.h:50 [inline]
 vma_interval_tree_insert_after+0x2be/0x2d0 mm/interval_tree.c:57
 dup_mmap kernel/fork.c:631 [inline]
 dup_mm kernel/fork.c:1521 [inline]
 copy_mm+0xba2/0x13e0 kernel/fork.c:1573
 copy_process+0x1149/0x3290 kernel/fork.c:2264
 kernel_clone+0x21e/0x9e0 kernel/fork.c:2662
 __do_sys_clone kernel/fork.c:2788 [inline]
 __se_sys_clone kernel/fork.c:2772 [inline]
 __x64_sys_clone+0x23f/0x290 kernel/fork.c:2772
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f5ba9ffe793
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffe18ff1588 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5ba9ffe793
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00005555571697d0 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

The buggy address belongs to the page:
page:ffffea0007000000 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x1c0000
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea0007010008 ffffea0006ff0008 0000000000000000
raw: 0000000000000000 000000000000000a 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff8881bfffff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881bfffff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881c0000000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                      ^
 ffff8881c0000080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881c0000100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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