================================================================== BUG: KASAN: slab-use-after-free in add_delayed_ref+0x12ca/0x1e00 fs/btrfs/delayed-ref.c:1077 Read of size 8 at addr ffff8880326976f8 by task syz.4.124/5871 CPU: 0 UID: 0 PID: 5871 Comm: syz.4.124 Not tainted 6.12.0-rc2-next-20241010-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 add_delayed_ref+0x12ca/0x1e00 fs/btrfs/delayed-ref.c:1077 btrfs_alloc_tree_block+0xdfb/0x1440 fs/btrfs/extent-tree.c:5209 btrfs_force_cow_block+0x526/0x1da0 fs/btrfs/ctree.c:573 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4314 btrfs_create_new_inode+0xe27/0x1f60 fs/btrfs/inode.c:6344 btrfs_create_common+0x1d4/0x2e0 fs/btrfs/inode.c:6578 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4257 do_mkdirat+0x264/0x3a0 fs/namei.c:4280 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 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: 0033:0x7fa94477dff9 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:00007fa9455d3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fa944935f80 RCX: 00007fa94477dff9 RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 00007fa9447f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa944935f80 R15: 00007ffdfd4b6a08 Allocated by task 5871: 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:4094 [inline] slab_alloc_node mm/slub.c:4143 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4150 add_delayed_ref+0x13a/0x1e00 fs/btrfs/delayed-ref.c:1020 btrfs_alloc_tree_block+0xdfb/0x1440 fs/btrfs/extent-tree.c:5209 btrfs_force_cow_block+0x526/0x1da0 fs/btrfs/ctree.c:573 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4314 btrfs_create_new_inode+0xe27/0x1f60 fs/btrfs/inode.c:6344 btrfs_create_common+0x1d4/0x2e0 fs/btrfs/inode.c:6578 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4257 do_mkdirat+0x264/0x3a0 fs/namei.c:4280 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 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 1588: 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:2329 [inline] slab_free mm/slub.c:4588 [inline] kmem_cache_free+0x1a2/0x440 mm/slub.c:4690 btrfs_put_delayed_ref_head fs/btrfs/delayed-ref.h:358 [inline] cleanup_ref_head fs/btrfs/extent-tree.c:1932 [inline] __btrfs_run_delayed_refs+0x3d34/0x4680 fs/btrfs/extent-tree.c:2113 btrfs_run_delayed_refs+0xe3/0x2c0 fs/btrfs/extent-tree.c:2213 btrfs_commit_transaction+0x4be/0x3740 fs/btrfs/transaction.c:2197 btrfs_qgroup_rescan_worker+0x17ac/0x1c60 fs/btrfs/qgroup.c:3864 btrfs_work_helper+0x390/0xc50 fs/btrfs/async-thread.c:314 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff8880326976f8 which belongs to the cache btrfs_delayed_ref_head of size 328 The buggy address is located 0 bytes inside of freed 328-byte region [ffff8880326976f8, ffff888032697840) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x32696 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88802f745000 ffffea0000c55800 0000000000000005 raw: 0000000000000000 0000000080140014 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88802f745000 ffffea0000c55800 0000000000000005 head: 0000000000000000 0000000080140014 00000001f5000000 0000000000000000 head: 00fff00000000001 ffffea0000c9a581 ffffffffffffffff 0000000000000000 head: ffff888000000002 0000000000000000 00000000ffffffff 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5619, tgid 5618 (syz.1.73), ts 78343819338, free_ts 78335798051 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3129/0x3270 mm/page_alloc.c:3493 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4769 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x120 mm/slub.c:2399 allocate_slab+0x5a/0x2f0 mm/slub.c:2565 new_slab mm/slub.c:2618 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3805 __slab_alloc+0x58/0xa0 mm/slub.c:3895 __slab_alloc_node mm/slub.c:3970 [inline] slab_alloc_node mm/slub.c:4131 [inline] kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4150 add_delayed_ref+0x13a/0x1e00 fs/btrfs/delayed-ref.c:1020 btrfs_alloc_tree_block+0xdfb/0x1440 fs/btrfs/extent-tree.c:5209 btrfs_force_cow_block+0x526/0x1da0 fs/btrfs/ctree.c:573 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4314 btrfs_create_new_inode+0xe27/0x1f60 fs/btrfs/inode.c:6344 page last free pid 5681 tgid 5681 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2674 mm_free_pgd kernel/fork.c:802 [inline] __mmdrop+0xb9/0x3d0 kernel/fork.c:918 exec_mmap+0x680/0x710 fs/exec.c:1014 begin_new_exec+0x12c0/0x2050 fs/exec.c:1270 load_elf_binary+0x966/0x2710 fs/binfmt_elf.c:996 search_binary_handler fs/exec.c:1742 [inline] exec_binprm fs/exec.c:1784 [inline] bprm_execve+0xaf8/0x1770 fs/exec.c:1835 do_execveat_common+0x55f/0x6f0 fs/exec.c:1942 do_execve fs/exec.c:2016 [inline] __do_sys_execve fs/exec.c:2092 [inline] __se_sys_execve fs/exec.c:2087 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2087 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 Memory state around the buggy address: ffff888032697580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888032697600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888032697680: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa ^ ffff888032697700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888032697780: 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