From patchwork Fri Oct 18 10:16:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matteo Martelli X-Patchwork-Id: 13841518 Received: from mail-wr1-f48.google.com (mail-wr1-f48.google.com [209.85.221.48]) (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 8A6D22022CE; Fri, 18 Oct 2024 10:17:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.48 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729246624; cv=none; b=XQtstmv9upVLWO+3TKedl6IGclC9AHbxrCtw/MOQxd6551j9DjGPmWLzhQeyLGs3lVJ9xqGT7RzEuze68XxDnI9uFKUqUbZ32lyp6WX3KXnDOyxfIgJaY7EsH9tBjBADfX3GAwppO/BTzP2oOoC2esShLI1fQ2UEMoFEY4RT3eo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729246624; c=relaxed/simple; bh=lLwcWxwjDNJi83wrQWAVlHlVnJucfvYmyQRif2fP9tA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=aTrB8XcUyMrM4shX26uKcoqu1CejHJoD4jOl1NK/I5jpHeT/rtX1mO/ddm9DaKSBB2athv1mULuni5+p077cm6Jf582HAuCUlWxrPn/gIXk3chdA53hKwisEmrpywWTZUQe7tk2eJI2p6+Dd7zDfuaheIGP6/+apkqVXhWUrEZ4= 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=V0et5gkD; arc=none smtp.client-ip=209.85.221.48 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="V0et5gkD" Received: by mail-wr1-f48.google.com with SMTP id ffacd0b85a97d-37d49a7207cso1359468f8f.0; Fri, 18 Oct 2024 03:17:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1729246621; x=1729851421; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=rwzowURA7LrdNAtuervNEFmMl54ysOzLP8Fuq/kRIC8=; b=V0et5gkDbUjGDH43nGDlNmoFBpKq4Q6Z/jsn4Of8jhubqHnbSfZPw3G77D95fLouyz HTRtVPMRuNF1csLp6QELOrtZiRTnVL8TCblkbfSvNYoDDhdNrAaavAuzKBw3MjNAMFhj IIp5C74Z1KJSAMWdZ1qJMMueOgA/iaA5OtNTiHnSyIR6oFpcX6ORUkZVPBAL8blmhKds zdD3HSfCHdXtb3YT03V46Z/zn0LhGc0hUWANB0teCeL9t2Nl+m9O7qPw38y0josThqZA uKOAqhHExvd81LXnvZCqd3Yur5+dOF58/VaOtFFCVjj+m1rR4Yh+6DE7NFooRZ4yuOBW TEJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729246621; x=1729851421; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=rwzowURA7LrdNAtuervNEFmMl54ysOzLP8Fuq/kRIC8=; b=UvjT3bsXwWFFLwmff1tDIzOTmKHvtvrbJIebdJHParWrWbnVvyKW54IwpmSm5kQw6A X2FVXJuuphg0n7ub0IvO0b+vWMqpL9Bi030rs9AYmCDW4iTWZyMNF+W6eEqPOeckojcL QOQ5zepCkfJXLMxpdyQd/1vl+LCHudpK852Kd8aHYCqVsoDLtZWqOOswYfDqHgYllAON Xcne/IDvwmyv1LDyeKdh71nHVw3CeXAfwJu8B7P+2EpwOPjAMQVHOUsU+kwe8QTdE9JJ BwgqTbyTR1WY5Us8mLKb67ZSXRl7X9pPHT/uMgWMdqgHFJiw7Di+t16bjWom8eHR8v6G mJ9w== X-Forwarded-Encrypted: i=1; AJvYcCV/Zas7VPD2f5OOjIafr8GZuIjwtE3qgdAuB0zrk8RzRMbmQN9ACoIZEWr2nMiTBZO64s/cbGNOu55J7g==@vger.kernel.org, AJvYcCVv7MR7unSxfDAZ9L2EVp73vA5YuTVDPH06baKRZRF3B4M+wObwLEeEZVFsqdOgg+HsjUl4ZslJyPc=@vger.kernel.org, AJvYcCWnnF9ZiXeMMiCx5kdJ1U+oDjpdrUt9LijteVxpIE5COVecqmSc521XoPzQoGkKBsG6C+2vnTSbKodxqNE=@vger.kernel.org X-Gm-Message-State: AOJu0Yz19u+rOiTg6kwdOaDEGD677GCfIKT+lL+BqR87kkKIEnzT1K3j zEuvX35M0YGMRyki6xjaxgB93c1ik7i54ak4JPXXkNpXZ9TY8JCM X-Google-Smtp-Source: AGHT+IHlbRgeDtSiwkVImTXi6eLGA0djtvQh25VEd8vaYpE2W6OyXUpc7iS8UBuQTPmhk1FJ6BJcKg== X-Received: by 2002:a5d:554a:0:b0:37d:43f1:57fd with SMTP id ffacd0b85a97d-37ea213717emr1388681f8f.6.1729246620727; Fri, 18 Oct 2024 03:17:00 -0700 (PDT) Received: from localhost (host-79-18-120-72.retail.telecomitalia.it. [79.18.120.72]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-37ecf089d52sm1543397f8f.61.2024.10.18.03.17.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Oct 2024 03:17:00 -0700 (PDT) From: Matteo Martelli Date: Fri, 18 Oct 2024 12:16:43 +0200 Subject: [PATCH v4 4/5] iio: ad7192: copy/release available filter frequencies to fix race Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241018-iio-read-avail-release-v4-4-53c8ac618585@gmail.com> References: <20241018-iio-read-avail-release-v4-0-53c8ac618585@gmail.com> In-Reply-To: <20241018-iio-read-avail-release-v4-0-53c8ac618585@gmail.com> To: Jonathan Cameron , Lars-Peter Clausen , Michael Hennerich , Alisa-Dariana Roman , Christian Eggers , Peter Rosin , Paul Cercueil , Sebastian Reichel Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-pm@vger.kernel.org, Matteo Martelli X-Mailer: b4 0.14.2 While available filter frequencies are being printed to sysfs by iio core (iio_read_channel_info_avail), the sampling frequency might be changed. This could cause the buffer shared with iio core to be corrupted. To prevent it, make a copy of the filter frequencies buffer and free it in the read_avail_release_resource callback. Signed-off-by: Matteo Martelli --- drivers/iio/adc/ad7192.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c index 7042ddfdfc03ee5ea58ca07fb1943feb6538175b..acf625ced0b21db8d44f77929e8a875b3c10e1b1 100644 --- a/drivers/iio/adc/ad7192.c +++ b/drivers/iio/adc/ad7192.c @@ -1056,12 +1056,19 @@ static int ad7192_read_avail(struct iio_dev *indio_dev, *length = ARRAY_SIZE(st->scale_avail) * 2; return IIO_AVAIL_LIST; - case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: - *vals = (int *)st->filter_freq_avail; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: { *type = IIO_VAL_FRACTIONAL; *length = ARRAY_SIZE(st->filter_freq_avail) * 2; + guard(mutex)(&st->lock); + + *vals = kmemdup_array((int *)st->filter_freq_avail, *length, + sizeof(int), GFP_KERNEL); + if (!*vals) + return -ENOMEM; + return IIO_AVAIL_LIST; + } case IIO_CHAN_INFO_OVERSAMPLING_RATIO: *vals = (int *)st->oversampling_ratio_avail; *type = IIO_VAL_INT; @@ -1073,6 +1080,14 @@ static int ad7192_read_avail(struct iio_dev *indio_dev, return -EINVAL; } +static void ad7192_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + if (mask == IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) + kfree(vals); +} + static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct ad7192_state *st = iio_priv(indio_dev); @@ -1098,6 +1113,7 @@ static const struct iio_info ad7192_info = { .write_raw = ad7192_write_raw, .write_raw_get_fmt = ad7192_write_raw_get_fmt, .read_avail = ad7192_read_avail, + .read_avail_release_resource = ad7192_read_avail_release_res, .attrs = &ad7192_attribute_group, .validate_trigger = ad_sd_validate_trigger, .update_scan_mode = ad7192_update_scan_mode, @@ -1108,6 +1124,7 @@ static const struct iio_info ad7194_info = { .write_raw = ad7192_write_raw, .write_raw_get_fmt = ad7192_write_raw_get_fmt, .read_avail = ad7192_read_avail, + .read_avail_release_resource = ad7192_read_avail_release_res, .validate_trigger = ad_sd_validate_trigger, }; @@ -1116,6 +1133,7 @@ static const struct iio_info ad7195_info = { .write_raw = ad7192_write_raw, .write_raw_get_fmt = ad7192_write_raw_get_fmt, .read_avail = ad7192_read_avail, + .read_avail_release_resource = ad7192_read_avail_release_res, .attrs = &ad7195_attribute_group, .validate_trigger = ad_sd_validate_trigger, .update_scan_mode = ad7192_update_scan_mode,