From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) (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 E3787336EC5 for ; Tue, 5 May 2026 11:13:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777979586; cv=none; b=KuHa93S7R5e0hSB99SBaxA7gyL1waRBfDBt+jnlb0LSDr5puB5pF7tL92KXN2KiNOf1d6DJMl/CB/tZ3SJ15mIqYsQDVnoARt74zlNC1LMd+0QZ/BlXaIE99Zwcc13JfKydPpDiwrBHpbQIyffCTOke0mFNkpa86weC7JuhEhLM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777979586; c=relaxed/simple; bh=9dD2I+0WrxMeGzTQybO0Oq66wv4w1ldPaLU+2HzXlvM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oekl0UNAJFmMFgq1StIf2igJLiZMB5dtc44yKKnb8kDztkveZq9m4tLnVfFnkbTARtvvmKO5lWCKHL7i9ETygO80Jb/l/qVAC8oHGppiuWmxOZ3oPciZVP7vN6+ox03h8A0z+UDSuFdQ/NBMeI5RhszTfpfAgElp61Qnpx0IxKM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=JGuzi/rn; arc=none smtp.client-ip=209.85.128.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JGuzi/rn" Received: by mail-wm1-f42.google.com with SMTP id 5b1f17b1804b1-4891c00e7aeso42932345e9.2 for ; Tue, 05 May 2026 04:13:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1777979583; x=1778584383; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=vLBbPQmiia3Jzj9CZTqoCt+pxP8PtFKqIf20080wUWw=; b=JGuzi/rnItf5/ZRnWvW++mE5Z3g8Nvne+jpVX303HGNY4NVYOPLdZCCEUg6eRbdYnH pSDEtMMRD5mjC41kfxwQMw3fAj0Lpx1lhkk8QqEAmUe6pD671V3qwHthAqIgkN+TlcnH YxTXwChP7/7tKJoX3uaP9bOWpkFjmgwG5jpREN7bXfAFHAyHr0KWgwFr8+H4rEA3mcnA tV1kWq9s0heGwTXRJ9ysEwKnRvbyMlLOmB8XWCtDppO7rWQ9XRXJ0wWxdEsXimsvYu8o DnnGshlxD6scVsGifXOKM45ZKY8sHKMTL4S26ajkok8U5Vrit35irBdL+JTitjbryO0Q ztTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777979583; x=1778584383; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=vLBbPQmiia3Jzj9CZTqoCt+pxP8PtFKqIf20080wUWw=; b=mXR5UeDJByY/QVBvu0EruVV0Yj5y64k8IoCaDFe0rW2KmWli5XHfzTnAiB7Bt6rQFO 0XPUZkng5xsnEmtCUjFc3LVnLKAuW2PZN9I8PhDnHonH9J2HkjVUE0Lsxd03QzjrujnA 7pwJZq+1d4EL9aDv9KYLVc+UYTxaEfDwdO8WAISl6yWy/gy61axYM++HouU9sLZZJcPo 31IT94BuUYQcKXiKFhu62xAidbCzEb7W9unNbRmkB7z95id8Vqs/mSiVvcjd4pEDYK7+ gHyxE6JrEnANepHn0j1FzayN8207scIJS0JEs4d5+raC90o0S22tVsN0odXUqjP4T9b+ 040A== X-Forwarded-Encrypted: i=1; AFNElJ9qZgGJ28/xKzm9Eqxd+5QVROGL62WvC64l6K94GDkbeQnyu+p4j/cTdDa4MjabyGAqf9UlTZjugu/tpOA=@vger.kernel.org X-Gm-Message-State: AOJu0YwrOjOHFt5i7cX/CjY18Hx+KLzzkZjxcE4iYizLi5t1ScRz3z7B TC13NQrih40FJuyWIhIBNiaiLqKRFzOmvjL5VR1ZZ3gHylVfFmHuwXRGTRxt X-Gm-Gg: AeBDieuviNCBVE1j04CSG2jg0zZlIhc7U01tJLCXEpWmcoReTDEm+dFu/W+tpDN03kw ajIsFax2bdcOYwDVbFzZXAsDAfQO2jIPrs8iwuze8w7hOMr967qMZb1rqYtEdLu6nfDIcDtj1yN 04feXLujNd57f/OHt1Eab99+6jSurjesrdHIB+PJaSOMQgBc1ksK56V59aNx45ZTCHwJFP8SW6b itjWhpFH7d6qAg/jWfGg+bg/jzYsa9SdulAIRFoVfWTqrAvGHs8OQMU3rEIZgjdN1uayB1wylpk v3kcbFc6gspQt8/+vZNcTKebH9AkpYKuVMIZ+OccefP3VOJI7PC8tt4iIUETn6qWkPLHGmb6ySl fUhZxUu8qsTfmzlB+w1V5fq/7P65F1C8cb5K8/bURlfGa4jIdpaAf9HEgdXnjrwx5XA+MV1eTY8 p8JGA= X-Received: by 2002:a05:600c:83c4:b0:48a:674d:e756 with SMTP id 5b1f17b1804b1-48d18be4526mr41493945e9.20.1777979583119; Tue, 05 May 2026 04:13:03 -0700 (PDT) Received: from debian.. ([2001:41d0:303:db6b::]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-45052a488d8sm3786183f8f.12.2026.05.05.04.13.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 May 2026 04:13:02 -0700 (PDT) From: Tristan Madani To: Viacheslav Dubeyko Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/2] hfs/hfsplus: zero-initialize buffer in hfs_bnode_read Date: Tue, 5 May 2026 11:12:59 +0000 Message-ID: <20260505111300.3592757-3-tristmd@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260505111300.3592757-1-tristmd@gmail.com> References: <20260501110218.29906-1-tristmd@gmail.com> <20260505111300.3592757-1-tristmd@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tristan Madani hfs_bnode_read() can return early without writing to the output buffer when is_bnode_offset_valid() fails or when check_and_correct_requested_ length() corrects the length to zero. Callers such as hfs_bnode_read_ u16() and hfs_bnode_read_u8() pass stack-allocated buffers and use the result unconditionally, leading to KMSAN uninit-value reports. Rather than initializing at each individual call site, zero the buffer at the start of hfs_bnode_read() before any validation checks. This ensures all callers in both hfs and hfsplus get a deterministic zero value regardless of which early-return path is taken. Reported-by: syzbot+217eb327242d08197efb@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=217eb327242d08197efb Tested-by: syzbot+217eb327242d08197efb@syzkaller.appspotmail.com Fixes: a431930c9bac ("hfs: fix slab-out-of-bounds in hfs_bnode_read()") Cc: stable@vger.kernel.org Signed-off-by: Tristan Madani --- fs/hfs/bnode.c | 2 ++ fs/hfsplus/bnode.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/fs/hfs/bnode.c b/fs/hfs/bnode.c index 9571f33b91085..25cef62fbba6d 100644 --- a/fs/hfs/bnode.c +++ b/fs/hfs/bnode.c @@ -64,6 +64,8 @@ void hfs_bnode_read(struct hfs_bnode *node, void *buf, u32 off, u32 len) u32 bytes_read; u32 bytes_to_read; + memset(buf, 0, len); + if (!is_bnode_offset_valid(node, off)) return; diff --git a/fs/hfsplus/bnode.c b/fs/hfsplus/bnode.c index f8b5a8ae58ff5..14d1af2c7ba93 100644 --- a/fs/hfsplus/bnode.c +++ b/fs/hfsplus/bnode.c @@ -25,6 +25,8 @@ void hfs_bnode_read(struct hfs_bnode *node, void *buf, u32 off, u32 len) struct page **pagep; u32 l; + memset(buf, 0, len); + if (!is_bnode_offset_valid(node, off)) return; -- 2.47.3