================================================================== BUG: KASAN: slab-use-after-free in ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline] BUG: KASAN: slab-use-after-free in ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996 Read of size 4 at addr ffff888042955000 by task syz.0.0/5339 CPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted 6.16.0-syzkaller-08685-g260f6f4fda93 #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_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline] ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996 ocfs2_claim_new_inode+0x332/0x7a0 fs/ocfs2/suballoc.c:2292 ocfs2_mknod_locked+0x100/0x250 fs/ocfs2/namei.c:634 ocfs2_mknod+0x10c7/0x2050 fs/ocfs2/namei.c:381 ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x14f4/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 file_open_name fs/open.c:1379 [inline] filp_open+0x176/0x1d0 fs/open.c:1399 coredump_file+0x33e/0xaf0 fs/coredump.c:931 vfs_coredump+0x16b1/0x2ab0 fs/coredump.c:1141 get_signal+0x1109/0x1340 kernel/signal.c:3019 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:224 [inline] irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:73 exc_page_fault+0x9f/0xf0 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f81fc18eb71 Code: 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:00000000fffffe10 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f81fc3b5fa0 RCX: 00007f81fc18eb69 RDX: 0000000000000000 RSI: 00000000fffffe10 RDI: 0000000000000000 RBP: 00007f81fc211df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f81fc3b5fa0 R15: 00007ffff6aecf88 Allocated by task 5310: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4179 [inline] kmem_cache_alloc_bulk_noprof+0x4e0/0x790 mm/slub.c:5410 mt_alloc_bulk lib/maple_tree.c:181 [inline] mas_alloc_nodes+0x447/0x8e0 lib/maple_tree.c:1271 mas_node_count_gfp lib/maple_tree.c:1331 [inline] mas_node_count lib/maple_tree.c:1345 [inline] mas_wr_preallocate lib/maple_tree.c:4286 [inline] mas_store_gfp+0x46c/0x860 lib/maple_tree.c:5464 vma_iter_clear_gfp include/linux/mm.h:883 [inline] do_vmi_align_munmap+0x2a7/0x420 mm/vma.c:1526 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1579 __vm_munmap+0x23b/0x3d0 mm/vma.c:3108 __do_sys_munmap mm/mmap.c:1084 [inline] __se_sys_munmap mm/mmap.c:1081 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5310: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2416 [inline] slab_free_freelist_hook mm/slub.c:2445 [inline] slab_free_bulk mm/slub.c:4703 [inline] kmem_cache_free_bulk+0x2d1/0x520 mm/slub.c:5282 mt_free_bulk lib/maple_tree.c:191 [inline] mas_destroy+0x165d/0x1c70 lib/maple_tree.c:5589 mas_store_gfp+0x7bc/0x860 lib/maple_tree.c:5478 vma_iter_clear_gfp include/linux/mm.h:883 [inline] do_vmi_align_munmap+0x2a7/0x420 mm/vma.c:1526 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1579 __vm_munmap+0x23b/0x3d0 mm/vma.c:3108 __do_sys_munmap mm/mmap.c:1084 [inline] __se_sys_munmap mm/mmap.c:1081 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888042955000 which belongs to the cache maple_node of size 256 The buggy address is located 0 bytes inside of freed 256-byte region [ffff888042955000, ffff888042955100) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x42955 anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801a4c0000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 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 4742, tgid 4742 (udevd), ts 35051070922, free_ts 35011964462 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2486 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2654 new_slab mm/slub.c:2708 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3890 __slab_alloc mm/slub.c:3980 [inline] __slab_alloc_node mm/slub.c:4055 [inline] slab_alloc_node mm/slub.c:4216 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4235 mt_alloc_one lib/maple_tree.c:176 [inline] mas_alloc_nodes+0x2e9/0x8e0 lib/maple_tree.c:1249 mas_node_count_gfp lib/maple_tree.c:1331 [inline] mas_preallocate+0x3ad/0x6f0 lib/maple_tree.c:5534 vma_iter_prealloc mm/vma.h:463 [inline] __mmap_new_vma mm/vma.c:2461 [inline] __mmap_region mm/vma.c:2622 [inline] mmap_region+0xe1e/0x1f30 mm/vma.c:2692 do_mmap+0xc45/0x10d0 mm/mmap.c:561 vm_mmap_pgoff+0x31b/0x4c0 mm/util.c:579 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 4742 tgid 4742 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 pagetable_free include/linux/mm.h:2886 [inline] pagetable_dtor_free include/linux/mm.h:2984 [inline] __tlb_remove_table+0x2d2/0x3b0 include/asm-generic/tlb.h:220 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Memory state around the buggy address: ffff888042954f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888042954f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888042955000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888042955080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888042955100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================