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 5C61734252D; Sat, 12 Sep 2026 07:40:11 +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=1789198812; cv=none; b=T9UdYXTWEr3v1TjPOLavUMIAW7Yi89KUPlMo6FjqbyVh+ierFM4S0yfaDhxBZWdbWWDRfXYLth28IYI90LEjNTRqy2JeQfHqefaBFv2+l6MOO7meUOBl2O8wAQu+wlSm3QqQC5nT6WIQKK1iDeOFwymmwCWy1w07O5SfI+nJarw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789198812; c=relaxed/simple; bh=ipbe99iWHbHQTD0UaOS+AY1GNftEp/YR04QgIRB1gUM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hc30M/cPxjk5+vpQ7J478sOOHJgf45BEd6Zn7wXMoKS643x2sOSpwLEEM2L+Ouug3BCqKztX4LeHj84D7lHrBXomL5SLG0qJ4ccKThEO2s+x/ASjE4RwOWvWfwOT4WMoAakPS8vqBt3K4OaRJGGI/fKFLjUM5BuCBr1VZx9NpMQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NYE4FVXI; 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="NYE4FVXI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 157951F000FF; Sat, 12 Sep 2026 07:40:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789198811; bh=Z2/bhzEeV1z5Tesu8lNYhPp7E81M1TkvHEGJtmhigVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NYE4FVXI3YmPdbU5skLW4z1g8hGsK8WRRYtZ3yvxYbPghcxsJn3zBDS5NbSKUxgC7 sJcJ+aKh09AJcVAPbmFpHjBcK6fw1PHbBg2e4qWzdmINqAVRXSTt47uyEOk4q846Xv C4DS0NJ+QQjmlMUfIhFWKo6XKEk6lq4NMohFzVsg= 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 7.2 0414/1815] libnvdimm/labels: Bound the on-media label size before the shift Date: Sat, 12 Sep 2026 08:36:04 +0200 Message-ID: <20260912065658.610625156@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065648.999753832@linuxfoundation.org> References: <20260912065648.999753832@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 7.2-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 ec12ce72cfe2c..dea2eee86d132 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