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JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
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BUG: KASAN: use-after-free in ocfs2_fault+0xcc/0x4ac fs/ocfs2/mmap.c:41
Read of size 8 at addr ffff0000cdf00808 by task syz.0.29/4553

CPU: 0 PID: 4553 Comm: syz.0.29 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call trace:
 dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351
 ocfs2_fault+0xcc/0x4ac fs/ocfs2/mmap.c:41
 __do_fault+0x11c/0x3d8 mm/memory.c:4278
 do_read_fault mm/memory.c:4629 [inline]
 do_fault mm/memory.c:4758 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x1cac/0x2fb0 mm/memory.c:5292
 faultin_page mm/gup.c:1026 [inline]
 __get_user_pages+0x33c/0x754 mm/gup.c:1250
 populate_vma_page_range+0x1f4/0x298 mm/gup.c:1607
 __mm_populate+0x210/0x334 mm/gup.c:1721
 mm_populate include/linux/mm.h:2891 [inline]
 vm_mmap_pgoff+0x1d8/0x294 mm/util.c:525
 ksys_mmap_pgoff+0x3b8/0x5a0 mm/mmap.c:1482
 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
 __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
 __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Allocated by task 4553:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x430 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x22c/0x308 mm/slub.c:3383
 vm_area_alloc+0x2c/0xe0 kernel/fork.c:459
 __mmap_region mm/mmap.c:2753 [inline]
 mmap_region+0xb88/0x1900 mm/mmap.c:2916
 do_mmap+0x9cc/0x1138 mm/mmap.c:1436
 vm_mmap_pgoff+0x190/0x294 mm/util.c:520
 ksys_mmap_pgoff+0x3b8/0x5a0 mm/mmap.c:1482
 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
 __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
 __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 4556:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0x118/0x314 mm/slub.c:3709
 vm_area_free+0x58/0x128 kernel/fork.c:486
 remove_vma mm/mmap.c:144 [inline]
 remove_mt mm/mmap.c:2319 [inline]
 do_mas_align_munmap+0xc6c/0xf38 mm/mmap.c:2595
 do_mas_munmap mm/mmap.c:2650 [inline]
 __mmap_region mm/mmap.c:2698 [inline]
 mmap_region+0x780/0x1900 mm/mmap.c:2916
 do_mmap+0x9cc/0x1138 mm/mmap.c:1436
 vm_mmap_pgoff+0x190/0x294 mm/util.c:520
 ksys_mmap_pgoff+0x3b8/0x5a0 mm/mmap.c:1482
 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
 __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
 __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000cdf00798
 which belongs to the cache vm_area_struct of size 152
The buggy address is located 112 bytes inside of
 152-byte region [ffff0000cdf00798, ffff0000cdf00830)

The buggy address belongs to the physical page:
page:00000000c27b56b7 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10df00
memcg:ffff0000c34ee801
flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000200 fffffc00032baa80 dead00000000000a ffff0000c03db680
raw: 0000000000000000 0000000080120012 00000001ffffffff ffff0000c34ee801
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000cdf00700: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff0000cdf00780: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000cdf00800: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb
                      ^
 ffff0000cdf00880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000cdf00900: fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb
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