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Buffer I/O error on dev loop3, logical block 3245768, async page read
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BUG: KASAN: use-after-free in sysv_new_block+0x790/0x970 fs/sysv/balloc.c:113
Read of size 4 at addr ffff8880784300c8 by task syz-executor201/5845

CPU: 0 UID: 0 PID: 5845 Comm: syz-executor201 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 sysv_new_block+0x790/0x970 fs/sysv/balloc.c:113
 alloc_branch fs/sysv/itree.c:135 [inline]
 get_block+0x30a/0x16d0 fs/sysv/itree.c:254
 __block_write_begin_int+0x50c/0x1a70 fs/buffer.c:2116
 sysv_make_empty+0xa7/0x580 fs/sysv/dir.c:262
 sysv_mkdir+0x7f/0x130 fs/sysv/namei.c:130
 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4311
 do_mkdirat+0x264/0x3a0 fs/namei.c:4334
 __do_sys_mkdirat fs/namei.c:4349 [inline]
 __se_sys_mkdirat fs/namei.c:4347 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9cd5bc7de9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 1d 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9cd5b76168 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f9cd5c516a8 RCX: 00007f9cd5bc7de9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 00000000ffffff9c
RBP: 00007f9cd5c516a0 R08: 00007f9cd5b766c0 R09: 0000000000000000
R10: 00007f9cd5b766c0 R11: 0000000000000246 R12: 00007f9cd5c516ac
R13: 0000000000000006 R14: 00007fff920d6970 R15: 00007fff920d6a58
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:1 mapping:0000000000000000 index:0x55cf52a7d pfn:0x78430
memcg:ffff888140adc000
anon flags: 0xfff00000020828(uptodate|lru|owner_2|swapbacked|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000020828 ffffea0001e4ffc8 ffffea0001e10c48 ffff88807ebc1111
raw: 000000055cf52a7d 0000000000000000 0000000100000000 ffff888140adc000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 5848, tgid 5848 (udevd), ts 62155502826, free_ts 55631127432
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x363e/0x3790 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 folio_alloc_mpol_noprof mm/mempolicy.c:2283 [inline]
 vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2313
 folio_prealloc+0x2e/0x170
 wp_page_copy mm/memory.c:3367 [inline]
 do_wp_page+0x11c4/0x5160 mm/memory.c:3759
 handle_pte_fault+0x111e/0x68a0 mm/memory.c:5817
 __handle_mm_fault mm/memory.c:5944 [inline]
 handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6112
 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
page last free pid 5820 tgid 5820 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_folios+0xf21/0x1a10 mm/page_alloc.c:2704
 folios_put_refs+0x76c/0x860 mm/swap.c:962
 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:332
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465
 vms_clear_ptes+0x437/0x530 mm/vma.c:1143
 vms_complete_munmap_vmas+0x210/0x8f0 mm/vma.c:1185
 do_vmi_align_munmap+0x5ef/0x6f0 mm/vma.c:1444
 do_vmi_munmap+0x24e/0x2d0 mm/vma.c:1492
 __vm_munmap+0x24c/0x480 mm/mmap.c:1367
 __do_sys_munmap mm/mmap.c:1384 [inline]
 __se_sys_munmap mm/mmap.c:1381 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1381
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807842ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888078430000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888078430080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                              ^
 ffff888078430100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888078430180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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