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BUG: KASAN: slab-use-after-free in ocfs2_fault+0xe8/0x3e0 fs/ocfs2/mmap.c:41
Read of size 8 at addr ffff888011dcd198 by task syz.0.0/5334

CPU: 0 UID: 0 PID: 5334 Comm: syz.0.0 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
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:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 ocfs2_fault+0xe8/0x3e0 fs/ocfs2/mmap.c:41
 __do_fault+0x135/0x390 mm/memory.c:5098
 do_read_fault mm/memory.c:5518 [inline]
 do_fault mm/memory.c:5652 [inline]
 do_pte_missing mm/memory.c:4160 [inline]
 handle_pte_fault+0x3f0c/0x61c0 mm/memory.c:5997
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0x1129/0x1bf0 mm/memory.c:6309
 faultin_page mm/gup.c:1193 [inline]
 __get_user_pages+0x1adc/0x4180 mm/gup.c:1491
 populate_vma_page_range+0x266/0x340 mm/gup.c:1929
 __mm_populate+0x27d/0x460 mm/gup.c:2032
 mm_populate include/linux/mm.h:3470 [inline]
 vm_mmap_pgoff+0x390/0x530 mm/util.c:584
 ksys_mmap_pgoff+0x4ee/0x720 mm/mmap.c:607
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a3f78d169
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:00007f0a4062c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f0a3f9a6080 RCX: 00007f0a3f78d169
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f0a3f80e2a0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0a3f9a6080 R15: 00007fff0cdce198
 </TASK>

Allocated by task 5334:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4151 [inline]
 slab_alloc_node mm/slub.c:4200 [inline]
 kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4207
 vm_area_alloc+0x24/0x140 kernel/fork.c:441
 __mmap_new_vma mm/vma.c:2359 [inline]
 __mmap_region mm/vma.c:2476 [inline]
 mmap_region+0x1acb/0x2ea0 mm/vma.c:2554
 do_mmap+0xd42/0x1420 mm/mmap.c:561
 vm_mmap_pgoff+0x2a2/0x530 mm/util.c:579
 ksys_mmap_pgoff+0x4ee/0x720 mm/mmap.c:607
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 16:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2389 [inline]
 slab_free_after_rcu_debug+0x11a/0x280 mm/slub.c:4696
 rcu_do_batch kernel/rcu/tree.c:2568 [inline]
 rcu_core+0xaac/0x17a0 kernel/rcu/tree.c:2824
 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579
 run_ksoftirqd+0xcf/0x130 kernel/softirq.c:968
 smpboot_thread_fn+0x576/0xaa0 kernel/smpboot.c:164
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbf/0xd0 mm/kasan/generic.c:548
 slab_free_hook mm/slub.c:2350 [inline]
 slab_free mm/slub.c:4646 [inline]
 kmem_cache_free+0x2ff/0x410 mm/slub.c:4748
 remove_vma mm/vma.c:430 [inline]
 vms_complete_munmap_vmas+0x655/0x8f0 mm/vma.c:1216
 __mmap_complete mm/vma.c:2426 [inline]
 __mmap_region mm/vma.c:2492 [inline]
 mmap_region+0x19bc/0x2ea0 mm/vma.c:2554
 do_mmap+0xd42/0x1420 mm/mmap.c:561
 vm_mmap_pgoff+0x2a2/0x530 mm/util.c:579
 ksys_mmap_pgoff+0x4ee/0x720 mm/mmap.c:607
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888011dcd140
 which belongs to the cache vm_area_struct of size 256
The buggy address is located 88 bytes inside of
 freed 256-byte region [ffff888011dcd140, ffff888011dcd240)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11dcd
memcg:ffff888012120281
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801c2a0b40 ffffea00004933c0 dead000000000006
raw: 0000000000000000 00000000800c000c 00000000f5000000 ffff888012120281
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4711, tgid 4711 (start-stop-daem), ts 45036322292, free_ts 43848221332
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717
 prep_new_page mm/page_alloc.c:1725 [inline]
 get_page_from_freelist+0x352b/0x36c0 mm/page_alloc.c:3652
 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2459 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2623
 new_slab mm/slub.c:2676 [inline]
 ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862
 __slab_alloc+0x58/0xa0 mm/slub.c:3952
 __slab_alloc_node mm/slub.c:4027 [inline]
 slab_alloc_node mm/slub.c:4188 [inline]
 kmem_cache_alloc_noprof+0x270/0x390 mm/slub.c:4207
 vm_area_alloc+0x24/0x140 kernel/fork.c:441
 __mmap_new_vma mm/vma.c:2359 [inline]
 __mmap_region mm/vma.c:2476 [inline]
 mmap_region+0x1acb/0x2ea0 mm/vma.c:2554
 do_mmap+0xd42/0x1420 mm/mmap.c:561
 vm_mmap_pgoff+0x2a2/0x530 mm/util.c:579
 elf_map fs/binfmt_elf.c:391 [inline]
 elf_load+0x25d/0x700 fs/binfmt_elf.c:414
 load_elf_binary+0x1093/0x28a0 fs/binfmt_elf.c:1172
 search_binary_handler fs/exec.c:1778 [inline]
 exec_binprm fs/exec.c:1810 [inline]
 bprm_execve+0x9a9/0x1430 fs/exec.c:1862
 do_execveat_common+0x57c/0x710 fs/exec.c:1968
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2680
 __free_pages mm/page_alloc.c:5044 [inline]
 free_reserved_page+0xce/0x120 mm/page_alloc.c:5947
 free_reserved_area+0x51/0xf0 mm/page_alloc.c:5933
 free_init_pages arch/x86/mm/init.c:937 [inline]
 free_kernel_image_pages arch/x86/mm/init.c:953 [inline]
 free_initmem+0x9a/0x110 arch/x86/mm/init.c:980
 kernel_init+0x31/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888011dcd080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888011dcd100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff888011dcd180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888011dcd200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888011dcd280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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