From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 56C26349AE8; Tue, 6 Jan 2026 17:18:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767719910; cv=none; b=nvDrKHD3Pxi1pzxnp8za2u2Au50Xc9XvKv/8xZw0Xw+fiutGtk0DV/WSj3cWWJhCL7gF923RAWzOv1G0IyIicsJi3TelVCNFS4BnF2pWGZdLbm2C92bM94MopX180GkgKVy9NviH8gWZnjR1iVsuwRiOLXx78+PMxCEiTMa8g5c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767719910; c=relaxed/simple; bh=cf5nt6KWWYV+IG7NgKBwktvcBr8kgw1skPIkYMsMDdk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rNwGglVXhgKjN0vUAWxbP6UVvWOO0XMEUokT9GFyJWc1LBqRV9FJ4FCIw7YL3oxuLN3TwbTtEN0HKX8ScwV4R+hf1yiFWsCCVDM3C4rQAaupvtkqJ18mYHv6W1dU1XDF996UInn+xRCSX8Ra5rVmlKtXSnmHKQvOB+ArUeVssUE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tzAgh0C5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="tzAgh0C5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7A51C116C6; Tue, 6 Jan 2026 17:18:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1767719910; bh=cf5nt6KWWYV+IG7NgKBwktvcBr8kgw1skPIkYMsMDdk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tzAgh0C5b4sYYLbJuefpeQht1AAygnrSwkXZeDJYXlQ9d6uMkXOth61xuAaGdfSYp defi2VxpW87Fw89ZU29sBjDgTGPYYouv734UGXsJMkiNN+/RYll8+/HLmlR1QVs3K2 5eGsndsVbt/BiwRrrvdcfo4P1xs/fuViRK4Wjzkw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Denis Sergeev , Guenter Roeck , Sasha Levin Subject: [PATCH 6.12 078/567] hwmon: (dell-smm) Limit fan multiplier to avoid overflow Date: Tue, 6 Jan 2026 17:57:40 +0100 Message-ID: <20260106170454.218295303@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260106170451.332875001@linuxfoundation.org> References: <20260106170451.332875001@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Denis Sergeev [ Upstream commit 46c28bbbb150b80827e4bcbea231560af9d16854 ] The fan nominal speed returned by SMM is limited to 16 bits, but the driver allows the fan multiplier to be set via a module parameter. Clamp the computed fan multiplier so that fan_nominal_speed * i8k_fan_mult always fits into a signed 32-bit integer and refuse to initialize the driver if the value is too large. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 20bdeebc88269 ("hwmon: (dell-smm) Introduce helper function for data init") Signed-off-by: Denis Sergeev Link: https://lore.kernel.org/r/20251209063706.49008-1-denserg.edu@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/dell-smm-hwmon.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c index f73f46193748..9df78861f5f8 100644 --- a/drivers/hwmon/dell-smm-hwmon.c +++ b/drivers/hwmon/dell-smm-hwmon.c @@ -75,6 +75,9 @@ #define DELL_SMM_NO_TEMP 10 #define DELL_SMM_NO_FANS 4 +/* limit fan multiplier to avoid overflow */ +#define DELL_SMM_MAX_FAN_MULT (INT_MAX / U16_MAX) + struct smm_regs { unsigned int eax; unsigned int ebx; @@ -1203,6 +1206,12 @@ static int dell_smm_init_data(struct device *dev, const struct dell_smm_ops *ops data->ops = ops; /* All options must not be 0 */ data->i8k_fan_mult = fan_mult ? : I8K_FAN_MULT; + if (data->i8k_fan_mult > DELL_SMM_MAX_FAN_MULT) { + dev_err(dev, + "fan multiplier %u is too large (max %u)\n", + data->i8k_fan_mult, DELL_SMM_MAX_FAN_MULT); + return -EINVAL; + } data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH; data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max); -- 2.51.0