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BUG: KASAN: use-after-free in udf_write_aext+0x5e9/0x7a0 fs/udf/inode.c:2110
Write of size 4 at addr ffff88801f993ff0 by task syz.0.36/3833

CPU: 1 PID: 3833 Comm: syz.0.36 Not tainted 5.15.162-syzkaller #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+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 udf_write_aext+0x5e9/0x7a0 fs/udf/inode.c:2110
 udf_add_entry+0x17b7/0x3350 fs/udf/namei.c:482
 udf_mkdir+0x1a8/0xaa0 fs/udf/namei.c:681
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4065
 do_mkdirat+0x260/0x520 fs/namei.c:4090
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb57c54dbd9
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:00007fb57afce048 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fb57c6dbf60 RCX: 00007fb57c54dbd9
RDX: 0000000000000000 RSI: 00000000200002c0 RDI: ffffffffffffff9c
RBP: 00007fb57c5bcaa1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000004d R14: 00007fb57c6dbf60 R15: 00007ffee69a9428
 </TASK>

The buggy address belongs to the page:
page:ffffea00007e64c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f993
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea00007d5608 ffffea00007e6488 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 3842, ts 74839817040, free_ts 74877757047
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 vm_area_alloc_pages mm/vmalloc.c:2868 [inline]
 __vmalloc_area_node mm/vmalloc.c:2924 [inline]
 __vmalloc_node_range+0x5ab/0x8c0 mm/vmalloc.c:3029
 vmalloc_user+0x70/0x80 mm/vmalloc.c:3165
 kcov_mmap+0x28/0x120 kernel/kcov.c:465
 call_mmap include/linux/fs.h:2177 [inline]
 mmap_region+0x10e7/0x1670 mm/mmap.c:1791
 do_mmap+0x78d/0xe00 mm/mmap.c:1575
 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551
 ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 __vunmap+0x8d4/0xa20 mm/vmalloc.c:2621
 kcov_mmap+0x8f/0x120 kernel/kcov.c:489
 call_mmap include/linux/fs.h:2177 [inline]
 mmap_region+0x10e7/0x1670 mm/mmap.c:1791
 do_mmap+0x78d/0xe00 mm/mmap.c:1575
 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551
 ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88801f993e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88801f993f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88801f993f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff88801f994000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801f994080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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