syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23657, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23657, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23658, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23658, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23659, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23659, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23660, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23660, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23661, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23661, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23662, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23662, async page read syz.0.0: attempt to access beyond end of device loop0: rw=0, sector=23663, nr_sectors = 1 limit=11 Buffer I/O error on dev loop0, logical block 23663, async page read ================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xe9/0x3d0 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff888042525368 by task syz.0.0/5325 CPU: 0 UID: 0 PID: 5325 Comm: syz.0.0 Not tainted 6.14.0-rc4-syzkaller-00212-g276f98efb64a #0 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+0xe9/0x3d0 fs/ocfs2/mmap.c:41 __do_fault+0x135/0x390 mm/memory.c:4988 do_read_fault mm/memory.c:5403 [inline] do_fault mm/memory.c:5537 [inline] do_pte_missing mm/memory.c:4058 [inline] handle_pte_fault mm/memory.c:5900 [inline] __handle_mm_fault+0x4c44/0x70f0 mm/memory.c:6043 handle_mm_fault+0x3e5/0x8d0 mm/memory.c:6212 do_user_addr_fault arch/x86/mm/fault.c:1388 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x2b9/0x8b0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:57 Code: f9 40 73 40 83 f9 08 73 21 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 RSP: 0018:ffffc9000d43fe18 EFLAGS: 00050246 RAX: 00007ffffffff001 RBX: 0000400000001000 RCX: 0000000000000008 RDX: 0000000000000001 RSI: 0000400000001000 RDI: ffffc9000d43fe80 RBP: ffffc9000d43ff00 R08: ffffc9000d43fe87 R09: 1ffff92001a87fd0 R10: dffffc0000000000 R11: fffff52001a87fd1 R12: 0000400000001000 R13: 0000000000000009 R14: ffffc9000d43fe80 R15: 0000000000000008 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] _inline_copy_from_user include/linux/uaccess.h:178 [inline] _copy_from_user+0x7b/0xb0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] __do_sys_sendfile64 fs/read_write.c:1416 [inline] __se_sys_sendfile64+0xcd/0x1e0 fs/read_write.c:1410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc04f78d169 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:00007fc05059e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fc04f9a6160 RCX: 00007fc04f78d169 RDX: 0000400000001000 RSI: 000000000000000b RDI: 000000000000000b RBP: 00007fc04f80e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc04f9a6160 R15: 00007ffc69023c98 Allocated by task 5320: 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:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4171 vm_area_alloc+0x24/0x1d0 kernel/fork.c:472 __mmap_new_vma mm/vma.c:2341 [inline] __mmap_region mm/vma.c:2457 [inline] mmap_region+0x1b04/0x2fa0 mm/vma.c:2535 do_mmap+0xecc/0x13a0 mm/mmap.c:561 vm_mmap_pgoff+0x214/0x430 mm/util.c:575 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:607 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5325: 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:2353 [inline] slab_free mm/slub.c:4609 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4711 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3065 [inline] call_rcu+0x168/0xac0 kernel/rcu/tree.c:3172 remove_vma mm/vma.c:419 [inline] vms_complete_munmap_vmas+0x65b/0x8f0 mm/vma.c:1202 __mmap_complete mm/vma.c:2407 [inline] __mmap_region mm/vma.c:2473 [inline] mmap_region+0x1998/0x2fa0 mm/vma.c:2535 do_mmap+0xecc/0x13a0 mm/mmap.c:561 vm_mmap_pgoff+0x214/0x430 mm/util.c:575 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:607 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880425252e8 which belongs to the cache vm_area_struct of size 184 The buggy address is located 128 bytes inside of freed 184-byte region [ffff8880425252e8, ffff8880425253a0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x42525 memcg:ffff888033e6af01 flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801c286b40 ffffea0000fd8500 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 ffff888033e6af01 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 5116, tgid 5116 (dhcpcd-run-hook), ts 40261622843, free_ts 40047653189 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4171 vm_area_alloc+0x24/0x1d0 kernel/fork.c:472 do_brk_flags+0x42c/0xd90 mm/vma.c:2596 __do_sys_brk mm/mmap.c:197 [inline] __se_sys_brk+0xa38/0xec0 mm/mmap.c:115 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 16 tgid 16 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 pagetable_free include/linux/mm.h:2917 [inline] pagetable_dtor_free include/linux/mm.h:3015 [inline] __tlb_remove_table+0x33c/0x420 include/asm-generic/tlb.h:216 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x76/0xf0 mm/mmu_gather.c:282 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff888042525200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888042525280: 00 00 00 00 00 fc fc fc fc fc fc fc fc fa fb fb >ffff888042525300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888042525380: fb fb fb fb fc fc fc fc fc fc fc fc 00 00 00 00 ffff888042525400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: f9 stc 1: 40 73 40 rex jae 0x44 4: 83 f9 08 cmp $0x8,%ecx 7: 73 21 jae 0x2a 9: 85 c9 test %ecx,%ecx b: 74 0f je 0x1c d: 8a 06 mov (%rsi),%al f: 88 07 mov %al,(%rdi) 11: 48 ff c7 inc %rdi 14: 48 ff c6 inc %rsi 17: 48 ff c9 dec %rcx 1a: 75 f1 jne 0xd 1c: c3 ret 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 28: 00 00 * 2a: 48 8b 06 mov (%rsi),%rax <-- trapping instruction 2d: 48 89 07 mov %rax,(%rdi) 30: 48 83 c6 08 add $0x8,%rsi 34: 48 83 c7 08 add $0x8,%rdi 38: 83 e9 08 sub $0x8,%ecx 3b: 74 df je 0x1c 3d: 83 f9 08 cmp $0x8,%ecx