syzbot


KASAN: out-of-bounds Read in __wait_on_bit

Status: moderation: reported on 2024/12/22 19:54
Subsystems: ntfs3
[Documentation on labels]
Reported-by: syzbot+0982b8c0ee625c16a15f@syzkaller.appspotmail.com
First crash: 8d04h, last: 2d17h

Sample crash report:
loop0: detected capacity change from 0 to 4096
ntfs3(loop0): Different NTFS sector size (1024) and media sector size (512).
overlayfs: upper fs does not support tmpfile.
overlayfs: upper fs does not support RENAME_WHITEOUT.
==================================================================
BUG: KASAN: out-of-bounds in __wait_on_bit+0xdf/0x2f0 kernel/sched/wait_bit.c:50
Read of size 8 at addr ffffc9000d345920 by task syz.0.0/5319

CPU: 0 UID: 0 PID: 5319 Comm: syz.0.0 Not tainted 6.13.0-rc4-syzkaller-00004-gf07044dd0df0 #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:
 <TASK>
 __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
 __wait_on_bit+0xdf/0x2f0 kernel/sched/wait_bit.c:50
 out_of_line_wait_on_bit+0x1d5/0x260 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 __wait_on_buffer fs/buffer.c:123 [inline]
 wait_on_buffer include/linux/buffer_head.h:414 [inline]
 __sync_dirty_buffer+0x2f7/0x390 fs/buffer.c:2858
 ntfs_write_bh+0x5f7/0x7c0 fs/ntfs3/fsntfs.c:1481
 mi_write+0x9b/0x1e0 fs/ntfs3/record.c:397
 indx_update_dup+0x69a/0x860 fs/ntfs3/index.c:2699
 ni_update_parent+0xa18/0xdd0 fs/ntfs3/frecord.c:3224
 ni_write_inode+0xd9f/0x1020 fs/ntfs3/frecord.c:3315
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745
 writeback_single_inode+0x1f3/0x660 fs/fs-writeback.c:1801
 sync_inode_metadata+0xc4/0x120 fs/fs-writeback.c:2871
 __generic_file_fsync+0x134/0x1a0 fs/libfs.c:1543
 generic_file_fsync+0x70/0xf0 fs/libfs.c:1573
 ovl_sync_file+0x3a/0x50 fs/overlayfs/copy_up.c:254
 ovl_copy_up_metadata+0xac1/0xef0 fs/overlayfs/copy_up.c:724
 ovl_copy_up_workdir fs/overlayfs/copy_up.c:816 [inline]
 ovl_do_copy_up fs/overlayfs/copy_up.c:1001 [inline]
 ovl_copy_up_one fs/overlayfs/copy_up.c:1202 [inline]
 ovl_copy_up_flags+0x2099/0x46f0 fs/overlayfs/copy_up.c:1257
 ovl_open+0x139/0x310 fs/overlayfs/file.c:211
 do_dentry_open+0xbe1/0x1b70 fs/open.c:945
 vfs_open+0x3e/0x330 fs/open.c:1075
 dentry_open+0x61/0xa0 fs/open.c:1098
 ima_calc_file_hash+0x16b/0x1b30 security/integrity/ima/ima_crypto.c:553
 ima_collect_measurement+0x520/0xb10 security/integrity/ima/ima_api.c:293
 process_measurement+0x1351/0x1fb0 security/integrity/ima/ima_main.c:372
 ima_file_check+0xd9/0x120 security/integrity/ima/ima_main.c:572
 security_file_post_open+0xb9/0x280 security/security.c:3121
 do_open fs/namei.c:3830 [inline]
 path_openat+0x2ccd/0x3590 fs/namei.c:3987
 do_filp_open+0x27f/0x4e0 fs/namei.c:4014
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1428
 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: 0033:0x7f2072385d29
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:00007f2073250038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2072575fa0 RCX: 00007f2072385d29
RDX: 0000000000000083 RSI: 0000000020000000 RDI: ffffffffffffff9c
RBP: 00007f2072401aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2072575fa0 R15: 00007ffdcaa6c058
 </TASK>

The buggy address belongs to stack of task syz.0.0/5319
 and is located at offset 32 in frame:
 out_of_line_wait_on_bit+0x0/0x260

This frame has 1 object:
 [32, 96) 'wq_entry'

The buggy address belongs to the virtual mapping at
 [ffffc9000d340000, ffffc9000d349000) created by:
 copy_process+0x5d1/0x3d50 kernel/fork.c:2224

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888042312000 pfn:0x42312
memcg:ffff88804208e102
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff888042312000 0000000000000000 00000001ffffffff ffff88804208e102
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 11, tgid 11 (kworker/u4:0), ts 66786456907, free_ts 66785874976
 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
 vm_area_alloc_pages mm/vmalloc.c:3591 [inline]
 __vmalloc_area_node mm/vmalloc.c:3669 [inline]
 __vmalloc_node_range_noprof+0x9c9/0x1380 mm/vmalloc.c:3846
 alloc_thread_stack_node kernel/fork.c:314 [inline]
 dup_task_struct+0x444/0x8c0 kernel/fork.c:1116
 copy_process+0x5d1/0x3d50 kernel/fork.c:2224
 kernel_clone+0x226/0x8e0 kernel/fork.c:2806
 user_mode_thread+0x132/0x1a0 kernel/fork.c:2884
 call_usermodehelper_exec_sync kernel/umh.c:132 [inline]
 call_usermodehelper_exec_work+0x9b/0x230 kernel/umh.c:163
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 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
page last free pid 5314 tgid 5314 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_folios+0xe39/0x18b0 mm/page_alloc.c:2706
 folios_put_refs+0x76c/0x860 mm/swap.c:962
 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:332
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465
 exit_mmap+0x496/0xc20 mm/mmap.c:1681
 __mmput+0x115/0x3c0 kernel/fork.c:1348
 exit_mm+0x220/0x310 kernel/exit.c:570
 do_exit+0x9ad/0x28e0 kernel/exit.c:925
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 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:
 ffffc9000d345800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000d345880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000d345900: f1 f1 f1 f1 00 00 00 00 00 00 00 00 f3 f3 f3 f3
                                  ^
 ffffc9000d345980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000d345a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/24 06:12 upstream f07044dd0df0 444551c4 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: out-of-bounds Read in __wait_on_bit
2024/12/18 19:48 upstream aef25be35d23 1432fc84 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: out-of-bounds Read in __wait_on_bit
* Struck through repros no longer work on HEAD.