syzbot

loop0: detected capacity change from 0 to 32768
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BUG: KASAN: use-after-free in __ocfs2_find_path+0x1ff/0x7e0 fs/ocfs2/alloc.c:1817
Read of size 4 at addr ffff88807f747000 by task syz-executor259/3640

CPU: 0 PID: 3640 Comm: syz-executor259 Not tainted 6.1.112-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 __ocfs2_find_path+0x1ff/0x7e0 fs/ocfs2/alloc.c:1817
 ocfs2_find_leaf+0xcb/0x220 fs/ocfs2/alloc.c:1931
 ocfs2_get_clusters_nocache+0x1a9/0xbe0 fs/ocfs2/extent_map.c:418
 ocfs2_get_clusters+0x5b5/0xbc0 fs/ocfs2/extent_map.c:621
 ocfs2_extent_map_get_blocks+0x248/0x7d0 fs/ocfs2/extent_map.c:668
 ocfs2_read_virt_blocks+0x313/0xab0 fs/ocfs2/extent_map.c:977
 ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
 ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
 ocfs2_find_entry+0x436/0x28c0 fs/ocfs2/dir.c:1080
 ocfs2_find_files_on_disk+0x10d/0x3a0 fs/ocfs2/dir.c:1982
 ocfs2_lookup_ino_from_name+0xad/0x1e0 fs/ocfs2/dir.c:2004
 _ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
 ocfs2_get_system_file_inode+0x314/0x7b0 fs/ocfs2/sysfile.c:112
 ocfs2_init_global_system_inodes+0x328/0x720 fs/ocfs2/super.c:457
 ocfs2_initialize_super fs/ocfs2/super.c:2250 [inline]
 ocfs2_fill_super+0x2f82/0x5730 fs/ocfs2/super.c:994
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faa9d005e9a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007faa9cfc0fd8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007faa9cfc0ff0 RCX: 00007faa9d005e9a
RDX: 0000000020004440 RSI: 0000000020000780 RDI: 00007faa9cfc0ff0
RBP: 0000000000000004 R08: 00007faa9cfc1030 R09: 0000000000004444
R10: 0000000001000000 R11: 0000000000000282 R12: 00007faa9cfc1030
R13: 0000000001000000 R14: 0000000000000003 R15: 0000000001000000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001fdd1c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x7f747
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001cac2c8 ffffea0002ff9108 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 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 3631, tgid 3631 (sshd), ts 53985253608, free_ts 53992703306
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558
 __folio_alloc+0xf/0x30 mm/page_alloc.c:5590
 vma_alloc_folio+0x486/0x990 mm/mempolicy.c:2243
 alloc_page_vma include/linux/gfp.h:284 [inline]
 do_anonymous_page mm/memory.c:4189 [inline]
 handle_pte_fault mm/memory.c:5027 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x2e8e/0x5340 mm/memory.c:5292
 do_user_addr_fault arch/x86/mm/fault.c:1340 [inline]
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x26f/0x620 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3510
 release_pages+0x2836/0x2b40 mm/swap.c:1055
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261
 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361
 unmap_region+0x29f/0x2f0 mm/mmap.c:2332
 do_mas_align_munmap+0xec8/0x15f0 mm/mmap.c:2582
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2640
 __vm_munmap+0x268/0x370 mm/mmap.c:2917
 __do_sys_munmap mm/mmap.c:2942 [inline]
 __se_sys_munmap mm/mmap.c:2939 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2939
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88807f746f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807f746f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807f747000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88807f747080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88807f747100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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