u64s 8 type dirent 4096:9097378837824744618:U32_MAX len 0 ver 0: file.cold -> 536870914 type reg, fixing dirent points to missing inode: u64s 8 type dirent 4096:9097378837824744618:U32_MAX len 0 ver 0: file.cold -> 536870914 type reg, fixing ================================================================== BUG: KASAN: use-after-free in check_dirent+0x1ec6/0x21c0 fs/bcachefs/fsck.c:2422 Read of size 1 at addr ffff8880520a0190 by task syz.0.9/5953 CPU: 0 UID: 0 PID: 5953 Comm: syz.0.9 Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 check_dirent+0x1ec6/0x21c0 fs/bcachefs/fsck.c:2422 bch2_check_dirents+0x408/0x780 fs/bcachefs/fsck.c:2447 bch2_run_recovery_pass+0x91/0x1a0 fs/bcachefs/recovery_passes.c:226 bch2_run_recovery_passes+0x40b/0x900 fs/bcachefs/recovery_passes.c:291 bch2_fs_recovery+0x256b/0x43e0 fs/bcachefs/recovery.c:936 bch2_fs_start+0x343/0x660 fs/bcachefs/super.c:1041 bch2_fs_get_tree+0x1176/0x17c0 fs/bcachefs/fs.c:2203 vfs_get_tree+0x8e/0x340 fs/super.c:1759 do_new_mount fs/namespace.c:3878 [inline] path_mount+0x14d4/0x1f30 fs/namespace.c:4205 do_mount fs/namespace.c:4218 [inline] __do_sys_mount fs/namespace.c:4429 [inline] __se_sys_mount fs/namespace.c:4406 [inline] __x64_sys_mount+0x28d/0x310 fs/namespace.c:4406 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fecad18e90a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007fecae044e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fecae044ef0 RCX: 00007fecad18e90a RDX: 00002000000058c0 RSI: 0000200000005900 RDI: 00007fecae044eb0 RBP: 00002000000058c0 R08: 00007fecae044ef0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000005900 R13: 00007fecae044eb0 R14: 00000000000058cb R15: 0000200000000000 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x520a0 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001482888 ffffea00011dbf88 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 5, migratetype Unmovable, gfp_mask 0x52800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP), pid 5953, tgid 5952 (syz.0.9), ts 97330826880, free_ts 111905210926 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x10c4/0x34c0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x223/0x24d0 mm/page_alloc.c:4740 __alloc_pages_noprof+0xb/0x1b0 mm/page_alloc.c:4774 __alloc_pages_node_noprof include/linux/gfp.h:265 [inline] alloc_pages_node_noprof include/linux/gfp.h:292 [inline] ___kmalloc_large_node+0x82/0x1e0 mm/slub.c:4262 __kmalloc_large_node_noprof+0x1c/0x70 mm/slub.c:4290 __do_kmalloc_node mm/slub.c:4306 [inline] __kvmalloc_node_noprof.cold+0xb/0x65 mm/slub.c:5003 btree_bounce_alloc+0x11e/0x210 fs/bcachefs/btree_io.c:123 bch2_btree_node_read_done+0xebc/0x4c90 fs/bcachefs/btree_io.c:1222 btree_node_read_work+0x568/0x1060 fs/bcachefs/btree_io.c:1358 bch2_btree_node_read+0x8bc/0xe90 fs/bcachefs/btree_io.c:1748 __bch2_btree_root_read fs/bcachefs/btree_io.c:1789 [inline] bch2_btree_root_read+0x2d1/0x470 fs/bcachefs/btree_io.c:1811 read_btree_roots fs/bcachefs/recovery.c:581 [inline] bch2_fs_recovery+0x203b/0x43e0 fs/bcachefs/recovery.c:928 bch2_fs_start+0x343/0x660 fs/bcachefs/super.c:1041 bch2_fs_get_tree+0x1176/0x17c0 fs/bcachefs/fs.c:2203 vfs_get_tree+0x8e/0x340 fs/super.c:1759 page last free pid 5953 tgid 5952 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] __free_pages_ok+0x622/0xe40 mm/page_alloc.c:1271 __folio_put+0x329/0x450 mm/swap.c:112 btree_bounce_free fs/bcachefs/btree_io.c:111 [inline] btree_node_sort+0xfe7/0x1580 fs/bcachefs/btree_io.c:379 bch2_btree_post_write_cleanup fs/bcachefs/btree_io.c:2293 [inline] bch2_btree_post_write_cleanup+0x145/0x600 fs/bcachefs/btree_io.c:2267 bch2_btree_node_prep_for_write+0x356/0x550 fs/bcachefs/btree_trans_commit.c:93 bch2_trans_lock_write+0x6ec/0x900 fs/bcachefs/btree_trans_commit.c:129 do_bch2_trans_commit fs/bcachefs/btree_trans_commit.c:862 [inline] __bch2_trans_commit+0x22c1/0x7f40 fs/bcachefs/btree_trans_commit.c:1070 bch2_trans_commit fs/bcachefs/btree_update.h:191 [inline] check_dirent+0xc4c/0x21c0 fs/bcachefs/fsck.c:2417 bch2_check_dirents+0x408/0x780 fs/bcachefs/fsck.c:2447 bch2_run_recovery_pass+0x91/0x1a0 fs/bcachefs/recovery_passes.c:226 bch2_run_recovery_passes+0x40b/0x900 fs/bcachefs/recovery_passes.c:291 bch2_fs_recovery+0x256b/0x43e0 fs/bcachefs/recovery.c:936 bch2_fs_start+0x343/0x660 fs/bcachefs/super.c:1041 bch2_fs_get_tree+0x1176/0x17c0 fs/bcachefs/fs.c:2203 vfs_get_tree+0x8e/0x340 fs/super.c:1759 do_new_mount fs/namespace.c:3878 [inline] path_mount+0x14d4/0x1f30 fs/namespace.c:4205 Memory state around the buggy address: ffff8880520a0080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880520a0100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880520a0180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880520a0200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880520a0280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== done bcachefs (loop0): check_xattrs... done bcachefs (loop0): check_root... done bcachefs (loop0): check_unreachable_inodes... done bcachefs (loop0): check_subvolume_structure... done bcachefs (loop0): check_directory_structure... done bcachefs (loop0): check_nlinks... done bcachefs (loop0): resume_logged_ops... done bcachefs (loop0): delete_dead_inodes... done bcachefs (loop0): set_fs_needs_rebalance... done bcachefs (loop0): Fixed errors, running fsck a second time to verify fs is clean bcachefs (loop0): check_alloc_info... done bcachefs (loop0): check_lrus... done bcachefs (loop0): check_btree_backpointers... done bcachefs (loop0): check_backpointers_to_extents... done bcachefs (loop0): check_extents_to_backpointers... done bcachefs (loop0): check_alloc_to_lru_refs... done bcachefs (loop0): bucket_gens_init... done bcachefs (loop0): check_snapshot_trees... done bcachefs (loop0): check_snapshots... done bcachefs (loop0): check_subvols... done bcachefs (loop0): check_subvol_children... done bcachefs (loop0): delete_dead_snapshots... done bcachefs (loop0): check_inodes... done bcachefs (loop0): check_extents... done bcachefs (loop0): check_indirect_extents... done bcachefs (loop0): check_dirents... done bcachefs (loop0): check_xattrs... done bcachefs (loop0): check_root... done bcachefs (loop0): check_unreachable_inodes... done bcachefs (loop0): check_subvolume_structure... done bcachefs (loop0): check_directory_structure... done bcachefs (loop0): check_nlinks... done bcachefs (loop0): resume_logged_ops... done bcachefs (loop0): delete_dead_inodes... done bcachefs (loop0): set_fs_needs_rebalance... done bcachefs (loop0): bch2_copygc_start(): error creating copygc thread EINTR bcachefs (loop0): error starting copygc thread bcachefs (loop0): bch2_fs_start(): error starting filesystem EINTR bcachefs (loop0): shutting down bcachefs (loop0): going read-only bcachefs (loop0): finished waiting for writes to stop bcachefs (loop0): flushing journal and stopping allocators, journal seq 38 bcachefs (loop0): flushing journal and stopping allocators complete, journal seq 38 bcachefs (loop0): clean shutdown complete, journal seq 39 bcachefs (loop0): marking filesystem clean bcachefs (loop0): shutdown complete bcachefs: bch2_fs_get_tree() error: EINTR syz.0.9 (5953) used greatest stack depth: 15144 bytes left