BUG: KASAN: use-after-free in get_max_inline_xattr_value_size+0x369/0x510 fs/ext4/inline.c:62
Read of size 4 at addr ffff8880392ee074 by task syz-executor.4/18882

CPU: 0 PID: 18882 Comm: syz-executor.4 Not tainted 6.3.0-rc7-syzkaller-00043-gaf67688dca57 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:319 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:430
 kasan_report+0x176/0x1b0 mm/kasan/report.c:536
 get_max_inline_xattr_value_size+0x369/0x510 fs/ext4/inline.c:62
 ext4_update_inline_dir fs/ext4/inline.c:1109 [inline]
 ext4_try_add_inline_entry+0x34b/0xb70 fs/ext4/inline.c:1306
 ext4_add_entry+0x535/0x1010 fs/ext4/namei.c:2384
 ext4_mkdir+0x553/0xce0 fs/ext4/namei.c:3006
 vfs_mkdir+0x29d/0x450 fs/namei.c:4038
 do_mkdirat+0x264/0x520 fs/namei.c:4061
 __do_sys_mkdir fs/namei.c:4081 [inline]
 __se_sys_mkdir fs/namei.c:4079 [inline]
 __x64_sys_mkdir+0x6e/0x80 fs/namei.c:4079
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8c54c8c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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:00007f8c4b41d168 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f8c54dac050 RCX: 00007f8c54c8c169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007f8c54ce7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe94b7c91f R14: 00007f8c4b41d300 R15: 0000000000022000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0000e4bb80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x392ee
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0000fc2c08 ffffea0000f97948 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 18845, tgid 18843 (syz-executor.2), ts 657641855996, free_ts 658650621221
 prep_new_page mm/page_alloc.c:2553 [inline]
 get_page_from_freelist+0x3246/0x33c0 mm/page_alloc.c:4326
 __alloc_pages+0x255/0x670 mm/page_alloc.c:5592
 __folio_alloc+0x13/0x30 mm/page_alloc.c:5624
 vma_alloc_folio+0x48a/0x9a0 mm/mempolicy.c:2244
 shmem_alloc_folio mm/shmem.c:1574 [inline]
 shmem_alloc_and_acct_folio+0x596/0xd40 mm/shmem.c:1598
 shmem_get_folio_gfp+0x14bd/0x36b0 mm/shmem.c:1937
 shmem_get_folio mm/shmem.c:2068 [inline]
 shmem_write_begin+0x172/0x4f0 mm/shmem.c:2561
 generic_perform_write+0x300/0x5e0 mm/filemap.c:3926
 __generic_file_write_iter+0x17a/0x400 mm/filemap.c:4054
 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4086
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7b2/0xbb0 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1454 [inline]
 free_pcp_prepare mm/page_alloc.c:1504 [inline]
 free_unref_page_prepare+0xe2f/0xe70 mm/page_alloc.c:3388
 free_unref_page_list+0x596/0x830 mm/page_alloc.c:3529
 release_pages+0x219e/0x2470 mm/swap.c:1042
 __pagevec_release+0x84/0x100 mm/swap.c:1062
 pagevec_release include/linux/pagevec.h:63 [inline]
 folio_batch_release include/linux/pagevec.h:132 [inline]
 shmem_undo_range+0x6b6/0x1dd0 mm/shmem.c:946
 shmem_truncate_range mm/shmem.c:1041 [inline]
 shmem_evict_inode+0x258/0x9f0 mm/shmem.c:1156
 evict+0x2a4/0x620 fs/inode.c:665
 __dentry_kill+0x436/0x650 fs/dcache.c:607
 dentry_kill+0xbb/0x290
 dput+0x1f3/0x420 fs/dcache.c:913
 __fput+0x5e4/0x890 fs/file_table.c:329
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86

Memory state around the buggy address:
 ffff8880392edf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880392edf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880392ee000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                             ^
 ffff8880392ee080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880392ee100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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