================================================================== BUG: KASAN: use-after-free in btrfs_sb fs/btrfs/super.h:14 [inline] BUG: KASAN: use-after-free in wait_subpage_spinlock+0x1be/0x210 fs/btrfs/inode.c:8232 Read of size 8 at addr ffff8880452e6678 by task syz-fuzzer/15259 CPU: 3 PID: 15259 Comm: syz-fuzzer Not tainted 6.2.0-rc3-syzkaller-00009-g5a41237ad1d4 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x461 mm/kasan/report.c:417 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517 btrfs_sb fs/btrfs/super.h:14 [inline] wait_subpage_spinlock+0x1be/0x210 fs/btrfs/inode.c:8232 __btrfs_release_folio fs/btrfs/inode.c:8261 [inline] btrfs_release_folio+0x109/0x130 fs/btrfs/inode.c:8271 filemap_release_folio+0x13f/0x1b0 mm/filemap.c:3967 shrink_folio_list+0x1ea9/0x3a60 mm/vmscan.c:2000 shrink_inactive_list mm/vmscan.c:2526 [inline] shrink_list mm/vmscan.c:2767 [inline] shrink_lruvec+0xd0e/0x27a0 mm/vmscan.c:5951 shrink_node_memcgs mm/vmscan.c:6138 [inline] shrink_node+0x8f2/0x1f40 mm/vmscan.c:6169 shrink_zones mm/vmscan.c:6407 [inline] do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:6469 try_to_free_pages+0x2e5/0x960 mm/vmscan.c:6704 __perform_reclaim mm/page_alloc.c:4750 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] __alloc_pages_slowpath.constprop.0+0x8b6/0x23d0 mm/page_alloc.c:5178 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5562 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2286 folio_alloc+0x20/0x70 mm/mempolicy.c:2296 filemap_alloc_folio+0x362/0x450 mm/filemap.c:972 __filemap_get_folio+0x32c/0xd80 mm/filemap.c:1966 filemap_fault+0x1598/0x23f0 mm/filemap.c:3164 __do_fault+0x107/0x600 mm/memory.c:4163 do_read_fault mm/memory.c:4514 [inline] do_fault mm/memory.c:4643 [inline] handle_pte_fault mm/memory.c:4931 [inline] __handle_mm_fault+0x22f2/0x3c90 mm/memory.c:5073 handle_mm_fault+0x1b6/0x850 mm/memory.c:5219 do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1428 handle_page_fault arch/x86/mm/fault.c:1519 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1575 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0033:0x44b036 Code: Unable to access opcode bytes at 0x44b00c. RSP: 002b:000000c013d2d988 EFLAGS: 00010283 RAX: 0000000000000017 RBX: 000000c013d2dbf0 RCX: 000000c013d2dac0 RDX: 0000000000000017 RSI: 0000000000000000 RDI: 0000000000000045 RBP: 000000c013d2d9c0 R08: 0000000001db77e0 R09: 000000000000004a R10: 000000c00f6df6c0 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000043 R14: 000000c0096a8680 R15: 0000000000000030 Allocated by task 16096: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:380 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_super+0x52/0xb60 fs/super.c:202 sget+0x10f/0x580 fs/super.c:643 btrfs_mount_root+0x619/0xc10 fs/btrfs/super.c:1501 legacy_get_tree+0x109/0x220 fs/fs_context.c:610 vfs_get_tree+0x8d/0x2f0 fs/super.c:1489 fc_mount fs/namespace.c:1149 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1179 vfs_kern_mount+0x40/0x60 fs/namespace.c:1166 btrfs_mount+0x23f/0xa90 fs/btrfs/super.c:1580 legacy_get_tree+0x109/0x220 fs/fs_context.c:610 vfs_get_tree+0x8d/0x2f0 fs/super.c:1489 do_new_mount fs/namespace.c:3145 [inline] path_mount+0x132a/0x1e20 fs/namespace.c:3475 do_mount fs/namespace.c:3488 [inline] __do_sys_mount fs/namespace.c:3697 [inline] __se_sys_mount fs/namespace.c:3674 [inline] __x64_sys_mount+0x283/0x300 fs/namespace.c:3674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 37: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] __cache_free mm/slab.c:3394 [inline] __do_kmem_cache_free mm/slab.c:3580 [inline] __kmem_cache_free+0xcd/0x3b0 mm/slab.c:3587 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0x7b/0x90 mm/kasan/generic.c:488 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x693/0x13b0 kernel/workqueue.c:1517 queue_work_on+0xf2/0x110 kernel/workqueue.c:1545 rcu_do_batch kernel/rcu/tree.c:2246 [inline] rcu_core+0x81f/0x1980 kernel/rcu/tree.c:2506 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0x7b/0x90 mm/kasan/generic.c:488 __call_rcu_common.constprop.0+0x99/0x820 kernel/rcu/tree.c:2755 __put_super fs/super.c:347 [inline] put_super fs/super.c:311 [inline] deactivate_locked_super+0x142/0x160 fs/super.c:343 deactivate_super+0xb1/0xd0 fs/super.c:363 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1291 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880452e6000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1656 bytes inside of 4096-byte region [ffff8880452e6000, ffff8880452e7000) The buggy address belongs to the physical page: page:ffffea000114b980 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x452e6 head:ffffea000114b980 order:1 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0x4fff00000010200(slab|head|node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000010200 ffff888012440900 ffffea0001836210 ffffea0001d96390 raw: 0000000000000000 ffff8880452e6000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 16096, tgid 16095 (syz-executor.3), ts 524582216742, free_ts 524503487664 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283 __alloc_pages_slowpath.constprop.0+0x36b/0x23d0 mm/page_alloc.c:5084 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5562 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2574 fallback_alloc+0x1e2/0x2d0 mm/slab.c:3117 __do_cache_alloc mm/slab.c:3221 [inline] slab_alloc_node mm/slab.c:3254 [inline] __kmem_cache_alloc_node+0x174/0x510 mm/slab.c:3544 kmalloc_trace+0x26/0x60 mm/slab_common.c:1062 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_super+0x52/0xb60 fs/super.c:202 sget+0x10f/0x580 fs/super.c:643 btrfs_mount_root+0x619/0xc10 fs/btrfs/super.c:1501 legacy_get_tree+0x109/0x220 fs/fs_context.c:610 vfs_get_tree+0x8d/0x2f0 fs/super.c:1489 fc_mount fs/namespace.c:1149 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1179 vfs_kern_mount+0x40/0x60 fs/namespace.c:1166 btrfs_mount+0x23f/0xa90 fs/btrfs/super.c:1580 legacy_get_tree+0x109/0x220 fs/fs_context.c:610 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare+0x65c/0xc00 mm/page_alloc.c:1496 free_unref_page_prepare mm/page_alloc.c:3369 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3464 slab_destroy mm/slab.c:1619 [inline] slabs_destroy+0x85/0xc0 mm/slab.c:1639 __cache_free_alien mm/slab.c:774 [inline] cache_free_alien mm/slab.c:790 [inline] ___cache_free+0x204/0x3d0 mm/slab.c:3421 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x4f/0x1a0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x192/0x220 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:761 [inline] slab_alloc_node mm/slab.c:3261 [inline] slab_alloc mm/slab.c:3270 [inline] __kmem_cache_alloc_lru mm/slab.c:3447 [inline] kmem_cache_alloc+0x225/0x460 mm/slab.c:3456 mt_alloc_one lib/maple_tree.c:152 [inline] mas_alloc_nodes+0x429/0x810 lib/maple_tree.c:1231 mas_node_count_gfp lib/maple_tree.c:1315 [inline] mas_preallocate+0x1bb/0x360 lib/maple_tree.c:5724 do_mas_align_munmap+0x129/0x1260 mm/mmap.c:2310 do_mas_munmap+0x26e/0x2c0 mm/mmap.c:2498 __vm_munmap+0x14f/0x290 mm/mmap.c:2775 __do_sys_munmap mm/mmap.c:2800 [inline] __se_sys_munmap mm/mmap.c:2797 [inline] __x64_sys_munmap+0x59/0x80 mm/mmap.c:2797 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880452e6500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880452e6580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880452e6600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880452e6680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880452e6700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================