================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xda/0x3e0 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff8880124f7198 by task syz.0.0/5322 CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 ocfs2_fault+0xda/0x3e0 fs/ocfs2/mmap.c:41 __do_fault+0x138/0x390 mm/memory.c:5323 do_read_fault mm/memory.c:5758 [inline] do_fault mm/memory.c:5892 [inline] do_pte_missing+0x21a2/0x37a0 mm/memory.c:4404 handle_pte_fault mm/memory.c:6276 [inline] __handle_mm_fault mm/memory.c:6414 [inline] handle_mm_fault+0x1b8c/0x32a0 mm/memory.c:6583 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x165b/0x29d0 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:3705 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd49019bf79 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd4910bc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fd490416090 RCX: 00007fd49019bf79 RDX: 00000000027ffff7 RSI: 0000000000600000 RDI: 0000200000000000 RBP: 00007fd4902327e0 R08: 0000000000000004 R09: 0000000000004000 R10: 0000000004012011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd490416128 R14: 00007fd490416090 R15: 00007ffe1a421258 Allocated by task 5322: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x370/0x6e0 mm/slub.c:5270 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2510 [inline] __mmap_region mm/vma.c:2752 [inline] mmap_region+0xf85/0x1f40 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free_after_rcu_debug+0x127/0x250 mm/slub.c:6737 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] __alloc_skb+0x1b7/0x390 net/core/skbuff.c:674 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack+0x14c/0xc90 net/ipv6/mcast.c:1775 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1886 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2025 mld_send_initial_cr+0x288/0x550 net/ipv6/mcast.c:2268 mld_dad_work+0x45/0x5b0 net/ipv6/mcast.c:2294 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2501 [inline] slab_free mm/slub.c:6674 [inline] kmem_cache_free+0x46e/0x610 mm/slub.c:6789 remove_vma mm/vma.c:467 [inline] vms_complete_munmap_vmas+0x625/0x890 mm/vma.c:1336 __mmap_complete+0x7b/0x610 mm/vma.c:2581 __mmap_region mm/vma.c:2761 [inline] mmap_region+0x141b/0x1f40 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880124f7140 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff8880124f7140, ffff8880124f7240) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x124f7 memcg:ffff88801cf21a01 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801bed5b40 dead000000000100 dead000000000122 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff88801cf21a01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4687, tgid 4687 (mount), ts 28454218234, free_ts 28451151881 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3a0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xd82/0x1760 mm/slub.c:4656 __kmem_cache_alloc_bulk+0x1ab/0x4d0 mm/slub.c:7439 refill_sheaf mm/slub.c:2650 [inline] __pcs_replace_empty_main+0x296/0x560 mm/slub.c:5023 alloc_from_pcs mm/slub.c:5121 [inline] slab_alloc_node mm/slub.c:5248 [inline] kmem_cache_alloc_noprof+0x454/0x6e0 mm/slub.c:5270 vm_area_dup+0x2b/0x680 mm/vma_init.c:123 __split_vma+0x1d5/0xa50 mm/vma.c:513 vms_gather_munmap_vmas+0x2f1/0x1320 mm/vma.c:1402 __mmap_setup mm/vma.c:2405 [inline] __mmap_region mm/vma.c:2734 [inline] mmap_region+0x838/0x1f40 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 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:1433 [inline] __free_frozen_pages+0xbf8/0xd70 mm/page_alloc.c:2973 __tlb_remove_table_free mm/mmu_gather.c:228 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:291 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1063 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffff8880124f7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880124f7100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff8880124f7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880124f7200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880124f7280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================