BTRFS info (device loop0): balance: start -d -m BTRFS info (device loop0): relocating block group 6881280 flags data|metadata BTRFS info (device loop0): relocating block group 5242880 flags data|metadata ================================================================== BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline] BUG: KASAN: slab-use-after-free in btrfs_backref_cleanup_node+0x2ea/0x4a0 fs/btrfs/backref.c:3154 Read of size 8 at addr ffff888056de0950 by task syz.0.0/5336 CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted 6.13.0-rc5-syzkaller-00006-g56e6a3499e14 #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:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 list_empty include/linux/list.h:373 [inline] btrfs_backref_cleanup_node+0x2ea/0x4a0 fs/btrfs/backref.c:3154 btrfs_backref_release_cache+0xbb/0x720 fs/btrfs/backref.c:3180 relocate_block_group+0xabf/0xd40 fs/btrfs/relocation.c:3741 btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087 btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494 __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278 btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655 btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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: 0033:0x7f242c785d29 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:00007f242d5cf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f242c976160 RCX: 00007f242c785d29 RDX: 0000000020000180 RSI: 00000000c4009420 RDI: 0000000000000007 RBP: 00007f242c801b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f242c976160 R15: 00007ffd5fccf248 Allocated by task 5336: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] btrfs_backref_alloc_node fs/btrfs/backref.c:3040 [inline] handle_indirect_tree_backref fs/btrfs/backref.c:3397 [inline] btrfs_backref_add_tree_node+0x16d2/0x2ed0 fs/btrfs/backref.c:3567 build_backref_tree+0x2bc/0xf30 fs/btrfs/relocation.c:434 relocate_tree_blocks+0x790/0x1dd0 fs/btrfs/relocation.c:2705 relocate_block_group+0x755/0xd40 fs/btrfs/relocation.c:3686 btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087 btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494 __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278 btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655 btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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 5336: 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:582 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:4613 [inline] kfree+0x196/0x430 mm/slub.c:4761 btrfs_backref_release_cache+0x5a/0x720 fs/btrfs/backref.c:3174 relocate_block_group+0xabf/0xd40 fs/btrfs/relocation.c:3741 btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087 btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494 __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278 btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655 btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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 ffff888056de0900 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 80 bytes inside of freed 128-byte region [ffff888056de0900, ffff888056de0980) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56de0 flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801ac41a00 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000001f5000000 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 0x52c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5316, tgid 5314 (syz.0.0), ts 78604736207, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x5a/0x2b0 mm/slub.c:2589 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] btrfs_backref_alloc_node+0x72/0x220 fs/btrfs/backref.c:3040 clone_backref_node fs/btrfs/relocation.c:512 [inline] btrfs_reloc_post_snapshot+0x9ff/0x16e0 fs/btrfs/relocation.c:4511 create_pending_snapshot+0x11da/0x2a10 fs/btrfs/transaction.c:1835 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1919 btrfs_commit_transaction+0xf11/0x3720 fs/btrfs/transaction.c:2398 create_snapshot+0x655/0x990 fs/btrfs/ioctl.c:875 btrfs_mksubvol+0x58f/0x710 fs/btrfs/ioctl.c:1029 page_owner free stack trace missing Memory state around the buggy address: ffff888056de0800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056de0880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888056de0900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888056de0980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056de0a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================