================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xe8/0x3e0 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff8880126ff7d8 by task syz.0.0/5330 CPU: 0 UID: 0 PID: 5330 Comm: syz.0.0 Not tainted 6.15.0-rc1-syzkaller-00325-g7cdabafc0012 #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: __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: 0033:0x7ff960b8d169 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:00007ff9619c7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff960da6080 RCX: 00007ff960b8d169 RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007ff960c0e990 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff960da6080 R15: 00007ffc66f8ca88 Allocated by task 5330: 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 71: 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 do_softirq+0x11f/0x1e0 kernel/softirq.c:480 __local_bh_enable_ip+0x1be/0x200 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x312/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 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 ffff8880126ff780 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff8880126ff780, ffff8880126ff880) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x126ff memcg:ffff888012184a01 anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801c2a0b40 ffffea00004bd5c0 dead000000000005 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff888012184a01 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 4701, tgid 4701 (swapon), ts 22973253904, free_ts 22957781573 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_dup+0x2b/0x5b0 kernel/fork.c:488 __split_vma+0x1b8/0xb20 mm/vma.c:477 vms_gather_munmap_vmas+0x325/0x13d0 mm/vma.c:1282 __mmap_prepare mm/vma.c:2260 [inline] __mmap_region mm/vma.c:2463 [inline] mmap_region+0xa13/0x2ea0 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 page last free pid 15 tgid 15 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 pagetable_free include/linux/mm.h:3002 [inline] pagetable_dtor_free include/linux/mm.h:3100 [inline] __tlb_remove_table+0x36b/0x460 include/asm-generic/tlb.h:215 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x79/0xf0 mm/mmu_gather.c:290 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 Memory state around the buggy address: ffff8880126ff680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880126ff700: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff8880126ff780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880126ff800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880126ff880: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================