From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793829438; b=zvgnSdVq799MepT08GoTTum+fu/OD3uJDgwajyspdJrYBMnNCEKqD1xmRalAqyAMUXzb HSZOGE0RFopdFR5SzReF+a04Lg6rC8RJLsS925vyXf0v0EYo3IHFwTKUZs1QtDDC4/TAJ wpiOI0nlkoNpsae/DdSwc6VBjNdIPiZXi0auiaeRUq4Jv4UvCIb6htOg8elr8I89Yq74U 14JPKBb64C8H/sHHzQGxbJJPO3QGgaQs6/aDFFasygXqayQGVxdbWiwPuQaLS3PW2NdPy K7pOkW5tY3VnFPGlXVbJ20GCuBvLFtLX5MBGglgpyysd5IhdHJ3Ko3BJOIolYerMG2A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829438; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=AUlaGiXmcRBDmEmcIQBz9BZGyhVFV+B9QBTfleul9iI=; b=itFj03A58u9yzCPn6kcjjrEGMD3hriTu480OwJUH8BilGxBmtKOPqpHpFXcuLHdBtW0V OLvVlbwLeOFEaR2xWLad+avYQvRpvKcZUitQAybX72FD7KzQ8bXO+V7aLOBaxHmCY1DXK srWzzgUkpZIdzIy0zmHSasHBiBEmVX1WIAT+A3gwsd4yeyD1b3nYKLWksR1/rpGnDL+yB +2u9LgeqtykKr0Jdq4SjKJjVja8dnazloQNmQl0BxZ16z4qe7QbpvZVqE9tsF+9V7UwZr CQ3bxLLwrbizotdmqhctMxh8GbYDGKk3M2GueBXZSYroKlidAfMBoaCuo/AftffbS5g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=yQ3VBtnf; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D2003606A863; Wed, 4 Nov 2026 21:57:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=yQ3VBtnf Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F7B91F00A1A; Wed, 4 Nov 2026 21:57:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829437; bh=AUlaGiXmcRBDmEmcIQBz9BZGyhVFV+B9QBTfleul9iI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yQ3VBtnfk82fkrDA1VlQM0zV0GR+mb+r0E8NZzCC1WGioAeX4yE/+A5bN+AZ1wOp3 3f0DCf4wfj4xJcQgj92A3Qx3XYtEin1TgK8Ge5VjLUAk8kaRhKnlmjItXEPi10+zEN ISmwHubhS/SEb9NU1lbjDYnLw0Ytj5IQILz1lZys= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xu Rao , Ulf Hansson , Sasha Levin Subject: [PATCH 6.18 0125/1005] mmc: block: reject invalid perdev_minors before division Date: Wed, 4 Nov 2026 15:57:38 -0500 Message-ID: <20261104211047.180426587@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xu Rao [ Upstream commit 5253aee00a4383cb0482d5e99bde48b8054ae2c0 ] The mmcblk.perdev_minors module parameter is parsed as a signed int and is used during mmc_blk_init() to compute the number of supported block devices. Passing perdev_minors=0 makes the init path divide by zero when it computes max_devices. Negative values are invalid as well and would make max_devices negative before it is later used as an IDA limit. Reject non-positive perdev_minors values before registering any mmcblk resources. Signed-off-by: Xu Rao Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin --- drivers/mmc/core/block.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index e8e45b161a398..5077842b286fe 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -3407,6 +3407,11 @@ static int __init mmc_blk_init(void) { int res; + if (perdev_minors <= 0) { + pr_err("mmcblk: invalid minors per device: %d\n", perdev_minors); + return -EINVAL; + } + res = bus_register(&mmc_rpmb_bus_type); if (res < 0) { pr_err("mmcblk: could not register RPMB bus type\n"); -- 2.53.0