From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f78.google.com (mail-oo1-f78.google.com [209.85.161.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EF4512EDD57 for ; Fri, 16 Jan 2026 21:04:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768597469; cv=none; b=fxaSsA1OkXR8UYFunV3Mz7bm+mEZKHuKIe9OCCl+JHTb4EdTT2WIuN6eMJBs+0UfoTxMerNG+SXFcuY9CgaUs7EYWmc8XOtg6aprjEQtL61NcGSAjh1NarYiwAJwYXjly61tXFod56XsVyvb7qEjJCvPnAnfmmlt0D0DJymMcZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768597469; c=relaxed/simple; bh=P7ozF7u87JAKtgxfxMSEhRy6CES4hE3SDifLRPHrx6k=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=omZWj3ps/yZLi2ZG+L+nkTthAGSj7CaxBsDM1Szc88UPvneu0yOkY1v3zIJdFKY+Q27dDRJyImJFBKZm+/1cHpVQS6Cl/ex2/Q+4f0dkQK8GqsrtrATZKvwzFBy0wEv+DQdhMmS/Ek3ZxIwUclZtU3MOkDWObrOomq9x8r0cXwY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f78.google.com with SMTP id 006d021491bc7-661125c8491so4638906eaf.3 for ; Fri, 16 Jan 2026 13:04:27 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768597467; x=1769202267; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=4BoW8Ww5HupkQo0MSjHqXCy4Na9QRURrT0hgV05jbOY=; b=LtTJZAGwpdV1T4DxAmdOHqRcf0L7ncNO+AOgYbbuogJYyEeAn+dtWLjVLCkpetjrMQ bYmIPRewBR6u0G2aUioHfMXN1qIHq0MM4aRY8xXZDCb0NTPHCFNkaFKs2qZ73sBl5e79 Zmrk+PS9J+/58RKBeOFBsbLsltQE7/pEIDTyhBQKD1pDODkin6cqsE8m4ogTdptlZBDJ XfIsAXIARik9xCugRs15ERG0Wiziid9pP86tPJGSbkv7qpoVcBjLiMtV3B48wMaqP4aJ Z4ucfvAvX4rKS+A43vX40+TBflAjQItt79EgFhZrKBO2Eb9N441UwRlpTUnp0FzUWR66 rL7g== X-Forwarded-Encrypted: i=1; AJvYcCV+xms22qffkyz0fHP9ps53/tiVjkJifJ+hxgu+mGtc2RWJILZstPqK5/xJ3OL30P1v87lh377beqM=@vger.kernel.org X-Gm-Message-State: AOJu0YzxHTiQoANN4DUXVUZv5yWa0tyBXTjdRY9UvFVqFENxCBlelZeI O8s3pQXX532OmcpmgIsYg66SO/tTs4M5t0pWIbSMYRDhpwcO193ixADCeR8+q5DxMQcDAF9uABw ib452lvDyDRgIwekjSulSqHibdbmjVOqLESRZ039CuPt62s5Tab2IlN0ySoU= Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a4a:ec4a:0:b0:65f:6c0f:fb33 with SMTP id 006d021491bc7-661179e45b7mr1728575eaf.55.1768597466926; Fri, 16 Jan 2026 13:04:26 -0800 (PST) Date: Fri, 16 Jan 2026 13:04:26 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <696aa7da.a70a0220.31956c.001a.GAE@google.com> Subject: [syzbot] [xfs?] KASAN: use-after-free Read in hpfs_bplus_lookup From: syzbot To: cem@kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, mikulas@artax.karlin.mff.cuni.cz, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: b71e635feefc Merge tag 'cgroup-for-6.19-rc5-fixes' of git:.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10efa99a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=7b058fb1d7dbe6b1 dashboard link: https://syzkaller.appspot.com/bug?extid=8debf4b3f7c7391cd8eb compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10cd15fa580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=152a4052580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/40abbbbc34a8/disk-b71e635f.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/74edfb8073f7/vmlinux-b71e635f.xz kernel image: https://storage.googleapis.com/syzbot-assets/3b5198043bfa/bzImage-b71e635f.xz mounted in repro #1: https://storage.googleapis.com/syzbot-assets/7f1692afbc9c/mount_0.gz fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=1609599a580000) mounted in repro #2: https://storage.googleapis.com/syzbot-assets/d09b0f5dc58e/mount_2.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8debf4b3f7c7391cd8eb@syzkaller.appspotmail.com hpfs: filesystem error: invalid number of hotfixes: 2066844986, used: 2066844985; already mounted read-only hpfs: filesystem error: improperly stopped hpfs: filesystem error: warning: spare dnodes used, try chkdsk hpfs: You really don't want any checks? You are crazy... hpfs: hpfs_map_sector(): read error hpfs: code page support is disabled hpfs: filesystem error: map_dirent: not a directory hpfs: hpfs_map_4sectors(): unaligned read hpfs: filesystem error: unable to find root dir ================================================================== BUG: KASAN: use-after-free in hpfs_bplus_lookup+0x4dc/0x860 fs/hpfs/anode.c:38 Read of size 4 at addr ffff888052abe004 by task syz.0.27/6198 CPU: 1 UID: 0 PID: 6198 Comm: syz.0.27 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 hpfs_bplus_lookup+0x4dc/0x860 fs/hpfs/anode.c:38 hpfs_bmap+0x22a/0x4d0 fs/hpfs/file.c:54 hpfs_get_block+0xa8/0x6e0 fs/hpfs/file.c:87 do_mpage_readpage+0x822/0x1990 fs/mpage.c:222 mpage_readahead+0x3b0/0x790 fs/mpage.c:371 read_pages+0x17a/0x580 mm/readahead.c:163 page_cache_ra_unbounded+0x68b/0x8c0 mm/readahead.c:302 filemap_get_pages+0x446/0x1ee0 mm/filemap.c:2690 filemap_read+0x3f9/0x11a0 mm/filemap.c:2800 __kernel_read+0x4d8/0x970 fs/read_write.c:530 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:480 [inline] ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline] ima_calc_file_hash+0x86a/0x1700 security/integrity/ima/ima_crypto.c:568 ima_collect_measurement+0x42e/0x900 security/integrity/ima/ima_api.c:293 process_measurement+0x112a/0x1a80 security/integrity/ima/ima_main.c:406 ima_file_check+0xd9/0x130 security/integrity/ima/ima_main.c:663 security_file_post_open+0xbb/0x290 security/security.c:2652 do_open fs/namei.c:4639 [inline] path_openat+0x3472/0x3df0 fs/namei.c:4796 do_filp_open+0x1fa/0x410 fs/namei.c:4823 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb59539f749 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:00007fff3ac53cb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fb5955f5fa0 RCX: 00007fb59539f749 RDX: 0000000000000000 RSI: 0000200000004280 RDI: ffffffffffffff9c RBP: 00007fb595423f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb5955f5fa0 R14: 00007fb5955f5fa0 R15: 0000000000000004 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x7fb58c615 pfn:0x52abe flags: 0x80000000000000(node=0|zone=1) raw: 0080000000000000 ffffea00014aafc8 ffff8880b8842d30 0000000000000000 raw: 00000007fb58c615 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 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO|__GFP_COMP), pid 6198, tgid 6198 (syz.0.27), ts 130045840131, free_ts 130049000115 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857 prep_new_page mm/page_alloc.c:1865 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486 folio_alloc_mpol_noprof mm/mempolicy.c:2505 [inline] vma_alloc_folio_noprof+0xe4/0x280 mm/mempolicy.c:2540 folio_prealloc+0x30/0x180 mm/memory.c:-1 alloc_anon_folio mm/memory.c:5165 [inline] do_anonymous_page mm/memory.c:5222 [inline] do_pte_missing+0x86a/0x27a0 mm/memory.c:4399 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0xcc1/0x1330 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 page last free pid 6198 tgid 6198 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1406 [inline] free_unref_folios+0xc28/0x1810 mm/page_alloc.c:3000 folios_put_refs+0x569/0x670 mm/swap.c:1002 free_pages_and_swap_cache+0x4be/0x520 mm/swap_state.c:358 __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:397 [inline] tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 vms_clear_ptes+0x42b/0x530 mm/vma.c:1238 vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1280 do_vmi_align_munmap+0x372/0x450 mm/vma.c:1539 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1587 __vm_munmap+0x207/0x380 mm/vma.c:3203 __do_sys_munmap mm/mmap.c:1077 [inline] __se_sys_munmap mm/mmap.c:1074 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1074 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888052abdf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888052abdf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888052abe000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888052abe080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888052abe100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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