From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9FF031FCFFC; Sat, 12 Sep 2026 14:27:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789223277; cv=none; b=iPIheGv06um0Datta90IZm1JL3Q5r/2goxG7y3YtNFdT/Y+UkKcBa1fwDuQjkPBaLzqYJ8kOsv0AwCJJDcDqZhAEr/R+Fu2Nx8lK3Xq5nYqv18+pCLadSSoQcM7P+nbSLye1xfJCq0vTPSOTYVqKs75eaHVURs/F+LkvTCN1QNo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789223277; c=relaxed/simple; bh=ljtMnjE47V/D6BVBbCyWGIweFiIXE0QieTAEU5rW8W4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jS2JdEqznii3IjOraLzlypOrZCdVY1zJt5+DNl8qyVVLt6e0BwpQgOiLfdQatKU7hVf0LuPWENPOg8rUpULqIpcYJ3CKiLXaUSdvvgzCYFvBBuA7n+VVBHeqHoND/3RWuG/WTlBLFN6vYzzV/VKwHcRaaPwjPP9QsTWGMVkLiQk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=O1NDaNo6; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="O1NDaNo6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50DB01F000FF; Sat, 12 Sep 2026 14:27:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789223276; bh=QJ7FMUHu4TaInxSP7YgDLKzjs3F025uXbITwDtSoYjE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=O1NDaNo6HXHn/gk/2/iH+QPlZM4mUbDpe2srhboPtVsYLm3+TxrG6nTLaovoT/UJS ytl52db03K5QujmIha6/6Jij9NqVvilYmpGTmRc4g+nCI2voSTBzCqThHRxLKCGNN/ d2IlCushYDOPTA6a+QJ6qIGvLxiewbMQxqj6ii0k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bryam Vargas , Alison Schofield , Sasha Levin Subject: [PATCH 6.6 0756/1424] libnvdimm/labels: Bound the on-media label size before the shift Date: Sat, 12 Sep 2026 08:53:08 +0200 Message-ID: <20260912065624.226888223@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.279695368@linuxfoundation.org> References: <20260912065607.279695368@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bryam Vargas [ Upstream commit 18f9124248ed7a9da1c31973b629dceef76a9b0c ] For a v1.2+ index, __nd_label_validate() computes the label size as 1 << (7 + nsindex[i]->labelsize), where labelsize is a u8 read from the label storage medium. A value of 25 or more makes the shift count reach or exceed the width of int -- undefined behavior -- and 24 already shifts into the sign bit. Only 0 (128-byte) and 1 (256-byte) are valid. Reject a labelsize above 1 before the shift. The result was rejected by the following size comparison anyway, so this only removes the undefined shift on a crafted or corrupted medium; conforming labels are unaffected. Fixes: 564e871aa66f ("libnvdimm, label: add v1.2 nvdimm label definitions") Signed-off-by: Bryam Vargas Reviewed-by: Alison Schofield Link: https://patch.msgid.link/20260624-b4-disp-d8279485-v3-2-cdb6cab28b41@proton.me Signed-off-by: Alison Schofield Signed-off-by: Sasha Levin --- drivers/nvdimm/label.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c index 584a9c27ce4bf..93ff219d91fc5 100644 --- a/drivers/nvdimm/label.c +++ b/drivers/nvdimm/label.c @@ -145,10 +145,21 @@ static int __nd_label_validate(struct nvdimm_drvdata *ndd) /* label sizes larger than 128 arrived with v1.2 */ version = __le16_to_cpu(nsindex[i]->major) * 100 + __le16_to_cpu(nsindex[i]->minor); - if (version >= 102) + if (version >= 102) { + /* + * labelsize feeds the shift below; only 0 (128-byte) + * and 1 (256-byte) are valid -- a larger value would + * overflow or exceed the width of int. + */ + if (nsindex[i]->labelsize > 1) { + dev_dbg(dev, "nsindex%d labelsize: %d invalid\n", + i, nsindex[i]->labelsize); + continue; + } labelsize = 1 << (7 + nsindex[i]->labelsize); - else + } else { labelsize = 128; + } if (labelsize != sizeof_namespace_label(ndd)) { dev_dbg(dev, "nsindex%d labelsize %d invalid\n", -- 2.53.0