syzbot


KASAN: use-after-free Read in ntfs_readpage

Status: upstream: reported C repro on 2023/03/18 08:03
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+ba146e220a3be3513bdc@syzkaller.appspotmail.com
First crash: 572d, last: 172d
Fix commit to backport (bisect log) :
tree: upstream
commit 7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89
Author: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Mon Jan 15 07:20:25 2024 +0000

  fs: Remove NTFS classic

  
Fix bisection: failed (error log, bisect log)
  
Bug presence (3)
Date Name Commit Repro Result
2024/04/21 linux-5.15.y (ToT) c52b9710c83d C [report] KASAN: use-after-free Read in ntfs_readpage
2023/05/10 upstream (ToT) 16a8829130ca C [report] KASAN: use-after-free Read in ntfs_read_folio
2024/04/21 upstream (ToT) 977b1ef51866 C Didn't crash
Fix bisection attempts (3)
Created Duration User Patch Repo Result
2024/04/21 21:10 5h43m fix candidate upstream OK (1) job log
2023/05/31 07:05 0m bisect fix linux-5.15.y error job log
2023/04/17 08:03 53m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
ntfs: (device loop0): parse_options(): Option utf8 is no longer supported, using option nls=utf8. Please use option nls=utf8 in the future and make sure utf8 is compiled either as a module or into the kernel.
ntfs: volume version 3.1.
==================================================================
BUG: KASAN: use-after-free in ntfs_readpage+0x7fb/0x2210 fs/ntfs/aops.c:488
Read of size 10 at addr ffff888072952170 by task syz-executor156/3501

CPU: 1 PID: 3501 Comm: syz-executor156 Not tainted 5.15.145-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:189
 memcpy+0x25/0x60 mm/kasan/shadow.c:65
 ntfs_readpage+0x7fb/0x2210 fs/ntfs/aops.c:488
 read_pages+0x605/0x8e0 mm/readahead.c:145
 page_cache_ra_unbounded+0x7b0/0x930 mm/readahead.c:239
 page_cache_sync_readahead include/linux/pagemap.h:833 [inline]
 filemap_get_pages mm/filemap.c:2551 [inline]
 filemap_read+0x71c/0x2980 mm/filemap.c:2634
 __kernel_read+0x5ac/0xa60 fs/read_write.c:443
 integrity_kernel_read+0xac/0xf0 security/integrity/iint.c:228
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xa5d/0x1c00 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x37e/0x800 security/integrity/ima/ima_api.c:255
 process_measurement+0x1363/0x21c0 security/integrity/ima/ima_main.c:351
 ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:533
 do_open fs/namei.c:3616 [inline]
 path_openat+0x2745/0x2f20 fs/namei.c:3748
 do_filp_open+0x21c/0x460 fs/namei.c:3775
 do_sys_openat2+0x13b/0x500 fs/open.c:1211
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_openat fs/open.c:1243 [inline]
 __se_sys_openat fs/open.c:1238 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1238
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7ffa8b6a0789
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 1a 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcd68a94a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffa8b6a0789
RDX: 0000000000141842 RSI: 0000000020000100 RDI: 00000000ffffff9c
RBP: 00007ffa8b6e20e5 R08: 000000000001ee7c R09: 00007ffcd68a9564
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcd68a9590
R13: 00007ffcd68a9670 R14: 431bde82d7b634db R15: 00007ffa8b6e201d
 </TASK>

The buggy address belongs to the page:
page:ffffea0001ca5480 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x72952
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001ca54c8 ffffea0001ca5448 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x1100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), pid 3501, ts 50983929210, free_ts 51014238464
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_pages_vma+0x39a/0x800 mm/mempolicy.c:2146
 do_anonymous_page mm/memory.c:3808 [inline]
 handle_pte_fault mm/memory.c:4619 [inline]
 __handle_mm_fault mm/memory.c:4756 [inline]
 handle_mm_fault+0x2f49/0x5950 mm/memory.c:4854
 do_user_addr_fault arch/x86/mm/fault.c:1397 [inline]
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x271/0x740 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page_list+0x1f7/0x8e0 mm/page_alloc.c:3433
 release_pages+0x1bb9/0x1f40 mm/swap.c:963
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:338
 unmap_region+0x304/0x350 mm/mmap.c:2668
 __do_munmap+0x12db/0x1740 mm/mmap.c:2899
 __vm_munmap+0x134/0x230 mm/mmap.c:2922
 __do_sys_munmap mm/mmap.c:2948 [inline]
 __se_sys_munmap mm/mmap.c:2944 [inline]
 __x64_sys_munmap+0x67/0x70 mm/mmap.c:2944
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888072952000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888072952080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888072952100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff888072952180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888072952200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/30 08:56 linux-5.15.y d93fa2c78854 fb427a07 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_readpage
2023/04/30 08:48 linux-5.15.y f48aeeaaa64c 62df2017 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_readpage
2023/03/18 08:02 linux-5.15.y 8020ae3c051d 7939252e .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ntfs_readpage
2023/12/29 04:58 linux-5.15.y d93fa2c78854 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_readpage
* Struck through repros no longer work on HEAD.