From nobody Wed Nov 27 00:24:38 2024 Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) (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 D3FE11D61BB; Tue, 15 Oct 2024 11:06:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990411; cv=none; b=p0I3QZDnvud1gly18yA6QXDo89K1AH0Hz6Trk0r0+toGm708ryvwuu6OsRM0J8HmS6VD55S+JZY/vMqb477PR2ywHlO8DM0IZhPBd/P/zZEyMYyjd8xNi5ZSjHvc1IVoI37qK5U+TGLOJOAXMzC47ph3WbO+q9S6PevozO2yOoo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990411; c=relaxed/simple; bh=0ClYzGYWuo9R4ytQT8+YomjzZyyvK/shpte3TSu50RA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=A0ilqnEZmggIkLM/mrm/bRIpuDm6gR+2AsRleg8Ga5d6y2DRqjapXBxk4Yc/Socag2WEgpC69J27C9iicOcHl6oW9zcLp1mYdXrKiQtW8TY89g3kS5VbrxLdkuabYeH+dIQTrorROFWOdlPQMfAL9U4TXqS1Op9snGDBkJux+2Q= 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=T5cY8OEe; arc=none smtp.client-ip=209.85.221.50 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="T5cY8OEe" Received: by mail-wr1-f50.google.com with SMTP id ffacd0b85a97d-37d6ff1cbe1so1646880f8f.3; Tue, 15 Oct 2024 04:06:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728990408; x=1729595208; 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=M4DbDXoWuKEPG/SkjaxUaXOQ8tk/bgeFy/xVB16h3Gg=; b=T5cY8OEeDesSAv5N1NkoOcub2uDk2BHD02tO6mhoWQG7rhuMT1YKvY86twnuBgU0st HISCgvf1ADOf1PmjE/mzYLzQoWW37dtClV4y7qPvcVVoHgUWru0z7Su7BsflbWZ9HuMp Um9aia28WsGt57eTLpwMdxHDktXgDhQ2UJiRJY1Y0Fmu3PwhiGa8mUz4xPheq4quJKr3 nmwPfjGoAc32LJz1wWox8ZD9oZtf3WJEtQtGaCwbqHFJB125tN71ZUODx0QeRn/W+nw7 K6yths6w3Rlbn6haV3Icmw0KoGtk5jEHVSOdzc5zr1fBy+dTHBRXi8sIT/kerBKAN2zh qbhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728990408; x=1729595208; 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=M4DbDXoWuKEPG/SkjaxUaXOQ8tk/bgeFy/xVB16h3Gg=; b=YfuRXclj1+6zouL7Gn6KmYbV/F0FJjoECelMLZuCXOg19pVWdqakGub3N0R3E5G9Aa TRmQYTX3iig/6TuQYXR2kkyOY1YLrYb8jWnXb7mgI8ipn2nRAU0uHIeObBr8ceHGpq31 Rug5f44eh85Xy5iGZxDQ/jd2ZMUpdFLuSQ1pXr83pXufOcz1gmmZS1dMO/ghJ0Cu5njw qvnJSdSWk2LSFsuedV++fwpaFJp984HYetFbDkMt2R+XlCNhcrPrV14uMNoOCzjgn1e1 74PqmeNXXWDLiKbbf2iZoK8viU6Yw0SUvKOCcqrb2MGAh4MXg020ZL+2xlWC2xAPWoB4 JAbQ== X-Forwarded-Encrypted: i=1; AJvYcCUAHG2c+I1/tOSrBrYCUgu+PvsKg9OdWSwQYYcxoF/rRUz1f9MXUkBJXFZdgHCDGclKXDxVq7HXH4apUQ==@vger.kernel.org, AJvYcCV1Vgimp/i258v3Rz34IoVl6AP6GtjlOW75mkdH7S2BfqDHCxtHZ6j9dtreAgF0bjvbOzsU75N/ans=@vger.kernel.org, AJvYcCViidfNt4fkx5217BezR6v3aOsoj3jJxNwYoDaWE/hiw9vEA3AwFSCLXpL8SX/xDDbP5z+2Hd3FQtHSsoA=@vger.kernel.org X-Gm-Message-State: AOJu0YzTi29TlgO/nUDdTd4VyvZUB38BAd94IojfqD+WQpWiSO3Q72jh witP9tZUIfLzjysHXe8j3yG6cethkhtSyJSeniQSZN97pmVBThQp X-Google-Smtp-Source: AGHT+IE0l9XSqoK/MJt2WGJVHE0pf1Cpqs08IgTd2WW2CgPkEqWoEJ//9zQqw6Fz/jISYRbbMQ2wLg== X-Received: by 2002:a5d:4403:0:b0:37c:cd38:c51e with SMTP id ffacd0b85a97d-37d5519911emr8465822f8f.1.1728990407867; Tue, 15 Oct 2024 04:06:47 -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-37d7fa87775sm1288894f8f.27.2024.10.15.04.06.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Oct 2024 04:06:47 -0700 (PDT) From: Matteo Martelli Date: Tue, 15 Oct 2024 13:06:34 +0200 Subject: [PATCH v3 1/5] iio: core: add read_avail_release_resource callback to fix race Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241015-iio-read-avail-release-v3-1-ac3e08f25cb3@gmail.com> References: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@gmail.com> In-Reply-To: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@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 Some iio drivers currently share an available info buffer that might be changed while iio core prints it to sysfs. To avoid the buffer corruption, add a release callback to let iio drivers allocate a copy of the available info buffer and later free it in the release callback. Such control is kept in the driver logic so that some driver that needs a big available info buffer might also perform some check to keep the copied buffer around in case no race has occurred. Signed-off-by: Matteo Martelli --- drivers/iio/industrialio-core.c | 14 +++++++++++--- include/linux/iio/iio.h | 4 ++++ 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-cor= e.c index 6a6568d4a2cb3a3f63381d5a6f25a2881b3ba2ed..4aea9de9f15a4d70f9d02fb3d47= df49eef8c8423 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -859,12 +859,20 @@ static ssize_t iio_read_channel_info_avail(struct dev= ice *dev, return ret; switch (ret) { case IIO_AVAIL_LIST: - return iio_format_avail_list(buf, vals, type, length); + ret =3D iio_format_avail_list(buf, vals, type, length); + break; case IIO_AVAIL_RANGE: - return iio_format_avail_range(buf, vals, type); + ret =3D iio_format_avail_range(buf, vals, type); + break; default: - return -EINVAL; + ret =3D -EINVAL; } + + if (indio_dev->info->read_avail_release_resource) + indio_dev->info->read_avail_release_resource( + indio_dev, this_attr->c, vals, this_attr->address); + + return ret; } =20 /** diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 3a9b57187a958d6e65c699cf7814df5bac9a99e3..03bb765670a0c5f0129fc677c3a= 4a4cb38f4dad1 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -491,6 +491,10 @@ struct iio_info { int *length, long mask); =20 + void (*read_avail_release_resource)(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask); + int (*write_raw)(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, --=20 2.47.0 From nobody Wed Nov 27 00:24:38 2024 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 38E971D8A0A; Tue, 15 Oct 2024 11:06:50 +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=1728990413; cv=none; b=B1muR/1Qgd6N5AZnqyreTOL41r6PSkYAlNHZuKo5eXcaQl7ppHHbk/V7BuuyRKJcroNtqpD/gqLyYw1tnADKx+/jWRvBOaoJ8QfFWyYzIj2RDM8uKCpQHOQX2h1mCA+68TLamfO3TvuNNAF+9nEHE0dp00F0YBpfiV8xyN+V1fE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990413; c=relaxed/simple; bh=7sklAWXfji9T1wFz6rAfasTB2Thy5tSs15h7yZqzF+0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=MVMcZxbXQ52GDkp2VPIm68w++0chvIGYz8SqJF49XhEPu92VpfIQ6dek5JAVE2J3/Bm1SC4L3k9IlnLJBib/vdIabGIiWUyBeGVrylBXXKMEQKERWH7E6HgU63GRNSQJ9+a3ICWeqRX4oYgoXmqENXM6FfDtiZ0T1YOmU1dgKaE= 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=YWIaZynb; 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="YWIaZynb" Received: by mail-wr1-f48.google.com with SMTP id ffacd0b85a97d-37d43a9bc03so3166929f8f.2; Tue, 15 Oct 2024 04:06:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728990409; x=1729595209; 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=7t1EeivanbjtmiS/C63NeyQb2kGTD8e2hmV9UzO5KnQ=; b=YWIaZynbWnCXZIlm6fwCVRp4NOhNNe0oSWAQwPd6CX7pB1cFyAD9tMjDFlYOZzd9P0 BPeYxWFeH1Ifx8rQS8TNpxHBofgbi3vK5AO84eZmzr/z0AlEA5RQ9DefFxjb+J8hRo01 9ScECVgK+zqbtTkXxUitgOctn3xmcUAgrNqA7ZxKOCTwBDhic4Mr5QG0UDS397jNgIf2 kRrDNw2cyfrcL/9m/6PGRwQoHofqiGlk0xeJKBvtD3m8Hgy5LKPrpw/ZE1DUVaAigzSj 2WekwJYw/SndxNv/zT+aPo77z+skAonWSYDOmztfV0FknkcbgXLw+9tJPYfCYEpkPDUj +W5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728990409; x=1729595209; 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=7t1EeivanbjtmiS/C63NeyQb2kGTD8e2hmV9UzO5KnQ=; b=uQ95U+NivygQRlznTYibcHkWyGDne3RMg0D6lCwGGWnga+zlS6cqsONzcYjfyzAH64 UxdlXw9VItgIlXVzo9ruWn+nQ2FMjJGgO0NrD7Uy4kzpMH1Pn5abyyNghZwAP6t0votf cje2pmyZ5lwe0mNC+DgGEny9MIDVjkNcGB6wayaLvNDqjf0g54i+8e1Macyme7jjtPDj NRcmIVVMVNv5rvuWyYCCMqPazmGLi6/mAyawmUBXaYgoOvSCwKAgeEkmleK10JWmFNo8 VpP+LRJjgscD0LO8NDej4KzGox7XFcGRZL7wsf4/umZCs2QTCB4le9K/HU9tZ2jvKKfQ R17w== X-Forwarded-Encrypted: i=1; AJvYcCUuQ+2Tj2o9XJzSOBvmlkbI1rq6KxJ/A8dhUtVwqPB9BJXJip6lg2+0KCXZSkZ/JWqQlC+256p5IJvubaM=@vger.kernel.org, AJvYcCVxujSis48qgX8KwR99NfAj8TfP0oodnug9Nk4bvIlKeqLx7y+cOkCPzYkjHJDyPKHvvjhRJk2hNFc=@vger.kernel.org, AJvYcCX6flGAtcrnvwPCKZ729SdozyehY2MqFWeZl/rtUXKk9GawYMX8V7SNeGraOC9/Hve2ttxIsZFIDHcdXw==@vger.kernel.org X-Gm-Message-State: AOJu0YyRzglGuDY3G69inZNSFa1FnHInhCRXtUrqgcjyWtsMeTtBKtwo fiU3rFD5h4byGBvGIc/HCTEnlY7anIGhMsnZfGyEjF1j2Gdc3ayt X-Google-Smtp-Source: AGHT+IHbd06YGB6Br+qw3ogI8F5eEDdorrA+TMPvBg6KlnNLQoKMOS+asZKXizlk+ay5W6eg9Wecvg== X-Received: by 2002:a5d:55c9:0:b0:37d:446b:7dfa with SMTP id ffacd0b85a97d-37d5ff6ccf4mr7370889f8f.39.1728990409190; Tue, 15 Oct 2024 04:06:49 -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-37d7fa7a173sm1293664f8f.15.2024.10.15.04.06.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Oct 2024 04:06:48 -0700 (PDT) From: Matteo Martelli Date: Tue, 15 Oct 2024 13:06:35 +0200 Subject: [PATCH v3 2/5] iio: consumers: copy/release available info from producer to fix race Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241015-iio-read-avail-release-v3-2-ac3e08f25cb3@gmail.com> References: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@gmail.com> In-Reply-To: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@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 Consumers need to call the producer's read_avail_release_resource() callback after reading producer's available info. To avoid a race condition with the producer unregistration, change inkern iio_channel_read_avail() so that it copies the available info from the producer and immediately calls its release callback with info_exists locked. Also, modify the users of iio_read_avail_channel_raw() and iio_read_avail_channel_attribute() to free the copied available buffers after calling these functions. Signed-off-by: Matteo Martelli --- drivers/iio/afe/iio-rescale.c | 8 ++++ drivers/iio/dac/dpot-dac.c | 8 ++++ drivers/iio/inkern.c | 68 ++++++++++++++++++++++++++----= ---- drivers/iio/multiplexer/iio-mux.c | 8 ++++ drivers/power/supply/ingenic-battery.c | 17 ++++++--- include/linux/iio/consumer.h | 4 +- 6 files changed, 90 insertions(+), 23 deletions(-) diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c index 56e5913ab82d1c045c9ca27012008a4495502cbf..78bb86c291706748b4072a48453= 2ad20c415ff9f 100644 --- a/drivers/iio/afe/iio-rescale.c +++ b/drivers/iio/afe/iio-rescale.c @@ -249,9 +249,17 @@ static int rescale_read_avail(struct iio_dev *indio_de= v, } } =20 +static void rescale_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + kfree(vals); +} + static const struct iio_info rescale_info =3D { .read_raw =3D rescale_read_raw, .read_avail =3D rescale_read_avail, + .read_avail_release_resource =3D rescale_read_avail_release_res, }; =20 static ssize_t rescale_read_ext_info(struct iio_dev *indio_dev, diff --git a/drivers/iio/dac/dpot-dac.c b/drivers/iio/dac/dpot-dac.c index f36f10bfb6be7863a56b911b5f58671ef530c977..43d68e17fc3a5fca59fad6ccf81= 8eeadfecdb8c1 100644 --- a/drivers/iio/dac/dpot-dac.c +++ b/drivers/iio/dac/dpot-dac.c @@ -108,6 +108,13 @@ static int dpot_dac_read_avail(struct iio_dev *indio_d= ev, return -EINVAL; } =20 +static void dpot_dac_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + kfree(vals); +} + static int dpot_dac_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) @@ -125,6 +132,7 @@ static int dpot_dac_write_raw(struct iio_dev *indio_dev, static const struct iio_info dpot_dac_info =3D { .read_raw =3D dpot_dac_read_raw, .read_avail =3D dpot_dac_read_avail, + .read_avail_release_resource =3D dpot_dac_read_avail_release_res, .write_raw =3D dpot_dac_write_raw, }; =20 diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index 7f325b3ed08fae6674245312cf8f57bb151006c0..7f50e33dc5084673aa66c25731a= dd0c314cb477d 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -760,9 +760,29 @@ static int iio_channel_read_avail(struct iio_channel *= chan, if (!iio_channel_has_available(chan->channel, info)) return -EINVAL; =20 - if (iio_info->read_avail) - return iio_info->read_avail(chan->indio_dev, chan->channel, - vals, type, length, info); + if (iio_info->read_avail) { + const int *vals_tmp; + int ret; + + ret =3D iio_info->read_avail(chan->indio_dev, chan->channel, + &vals_tmp, type, length, info); + if (ret < 0) + return ret; + + /* + * Copy the producer's avail buffer with lock_exists locked to + * avoid possible race with producer unregistration. + */ + *vals =3D kmemdup_array(vals_tmp, *length, sizeof(int), GFP_KERNEL); + if (!*vals) + return -ENOMEM; + + if (iio_info->read_avail_release_resource) + iio_info->read_avail_release_resource( + chan->indio_dev, chan->channel, vals_tmp, info); + + return ret; + } return -EINVAL; } =20 @@ -789,9 +809,11 @@ int iio_read_avail_channel_raw(struct iio_channel *cha= n, ret =3D iio_read_avail_channel_attribute(chan, vals, &type, length, IIO_CHAN_INFO_RAW); =20 - if (ret >=3D 0 && type !=3D IIO_VAL_INT) + if (ret >=3D 0 && type !=3D IIO_VAL_INT) { /* raw values are assumed to be IIO_VAL_INT */ + kfree(*vals); ret =3D -EINVAL; + } =20 return ret; } @@ -820,24 +842,31 @@ static int iio_channel_read_max(struct iio_channel *c= han, if (val2) *val2 =3D vals[5]; } - return 0; + ret =3D 0; + break; =20 case IIO_AVAIL_LIST: - if (length <=3D 0) - return -EINVAL; + if (length <=3D 0) { + ret =3D -EINVAL; + goto out; + } switch (*type) { case IIO_VAL_INT: *val =3D max_array(vals, length); + ret =3D 0; break; default: /* TODO: learn about max for other iio values */ - return -EINVAL; + ret =3D -EINVAL; } - return 0; + break; =20 default: - return -EINVAL; + ret =3D -EINVAL; } +out: + kfree(vals); + return ret; } =20 int iio_read_max_channel_raw(struct iio_channel *chan, int *val) @@ -876,24 +905,31 @@ static int iio_channel_read_min(struct iio_channel *c= han, if (val2) *val2 =3D vals[1]; } - return 0; + ret =3D 0; + break; =20 case IIO_AVAIL_LIST: - if (length <=3D 0) - return -EINVAL; + if (length <=3D 0) { + ret =3D -EINVAL; + goto out; + } switch (*type) { case IIO_VAL_INT: *val =3D min_array(vals, length); + ret =3D 0; break; default: /* TODO: learn about min for other iio values */ - return -EINVAL; + ret =3D -EINVAL; } - return 0; + break; =20 default: - return -EINVAL; + ret =3D -EINVAL; } +out: + kfree(vals); + return ret; } =20 int iio_read_min_channel_raw(struct iio_channel *chan, int *val) diff --git a/drivers/iio/multiplexer/iio-mux.c b/drivers/iio/multiplexer/ii= o-mux.c index 2953403bef53bbe47a97a8ab1c475ed88d7f86d2..31345437784b01c5d6f8ea70263= f4c2574388e7a 100644 --- a/drivers/iio/multiplexer/iio-mux.c +++ b/drivers/iio/multiplexer/iio-mux.c @@ -142,6 +142,13 @@ static int mux_read_avail(struct iio_dev *indio_dev, return ret; } =20 +static void mux_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + kfree(vals); +} + static int mux_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) @@ -171,6 +178,7 @@ static int mux_write_raw(struct iio_dev *indio_dev, static const struct iio_info mux_info =3D { .read_raw =3D mux_read_raw, .read_avail =3D mux_read_avail, + .read_avail_release_resource =3D mux_read_avail_release_res, .write_raw =3D mux_write_raw, }; =20 diff --git a/drivers/power/supply/ingenic-battery.c b/drivers/power/supply/= ingenic-battery.c index 0a40f425c27723ccec49985b8b5e14a737b6a7eb..3db000d9fff9a7a681963131454= 7b3d16db7f967 100644 --- a/drivers/power/supply/ingenic-battery.c +++ b/drivers/power/supply/ingenic-battery.c @@ -12,6 +12,7 @@ #include #include #include +#include =20 struct ingenic_battery { struct device *dev; @@ -79,8 +80,10 @@ static int ingenic_battery_set_scale(struct ingenic_batt= ery *bat) dev_err(bat->dev, "Unable to read channel avail scale\n"); return ret; } - if (ret !=3D IIO_AVAIL_LIST || scale_type !=3D IIO_VAL_FRACTIONAL_LOG2) - return -EINVAL; + if (ret !=3D IIO_AVAIL_LIST || scale_type !=3D IIO_VAL_FRACTIONAL_LOG2) { + ret =3D -EINVAL; + goto out; + } =20 max_mV =3D bat->info->voltage_max_design_uv / 1000; =20 @@ -99,7 +102,8 @@ static int ingenic_battery_set_scale(struct ingenic_batt= ery *bat) =20 if (best_idx < 0) { dev_err(bat->dev, "Unable to find matching voltage scale\n"); - return -EINVAL; + ret =3D -EINVAL; + goto out; } =20 /* Only set scale if there is more than one (fractional) entry */ @@ -109,10 +113,13 @@ static int ingenic_battery_set_scale(struct ingenic_b= attery *bat) scale_raw[best_idx + 1], IIO_CHAN_INFO_SCALE); if (ret) - return ret; + goto out; } =20 - return 0; + ret =3D 0; +out: + kfree(scale_raw); + return ret; } =20 static enum power_supply_property ingenic_battery_properties[] =3D { diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index 333d1d8ccb37f387fe531577ac5e0bfc7f752cec..e3e268d2574b3e01c9412449d90= d627de7efcd84 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -316,7 +316,7 @@ int iio_read_min_channel_raw(struct iio_channel *chan, = int *val); /** * iio_read_avail_channel_raw() - read available raw values from a given c= hannel * @chan: The channel being queried. - * @vals: Available values read back. + * @vals: Available values read back. Must be freed after use. * @length: Number of entries in vals. * * Returns an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST. @@ -334,7 +334,7 @@ int iio_read_avail_channel_raw(struct iio_channel *chan, /** * iio_read_avail_channel_attribute() - read available channel attribute v= alues * @chan: The channel being queried. - * @vals: Available values read back. + * @vals: Available values read back. Must be freed after use. * @type: Type of values read back. * @length: Number of entries in vals. * @attribute: info attribute to be read back. --=20 2.47.0 From nobody Wed Nov 27 00:24:38 2024 Received: from mail-wm1-f50.google.com (mail-wm1-f50.google.com [209.85.128.50]) (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 04B621E7664; Tue, 15 Oct 2024 11:06:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990415; cv=none; b=D3w+Q+WB0CQJd5Lx0YeXh8YYweN5BBesqodwx8PjFpq2tX49wUD15YenyMkxkqd06kx73OwoaJZ0CyZp4ddYMNP8pDRqzWLmKJpOHts2S7pwdqYOZxKp9Ts0092J6UWmIY6tym0TNEhEHljdXh05HpwceqCFv9hPbChYIsegeDs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990415; c=relaxed/simple; bh=QdYDXg+F9crN+GcA1VSjP47ejtoSADQbLgM8+WYO3yU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ggUSEnpKFds937f7GSKHacCpi63V4rqp0jLsIy+dI4gQKpzomOIVhmhbfbhxpA4msmpgUiN4CMBWrYTDycfik7YmQc9UTiF4YYa02838taWjoW1kgf5sZrGFuwpfnIpVJGZQQPcmJS1OqLknL2otbaIXpX69nwRoPFEYDuAsGKE= 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=fN7Rf8Mj; arc=none smtp.client-ip=209.85.128.50 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="fN7Rf8Mj" Received: by mail-wm1-f50.google.com with SMTP id 5b1f17b1804b1-430ee5c9570so61599655e9.3; Tue, 15 Oct 2024 04:06:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728990411; x=1729595211; 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=sBrQ02u0x+gOef7QkcexjhixwvYLcPbk6l/zE/g/i1o=; b=fN7Rf8MjGYIWdJa6QUVjqiWgujkJiBChwnIRs+31EgGkJFJDSJz2t1UM+C/9KI5YKT ElFWDv3Q7WkNqrdiS8RsVaMzqUIXXA9ES8xaMXspif8vi0xiXtVkQFt7kRblq0P8bCnv NkjqTcomN8cvQzgq7iWLx4UiT5BVV0StQjvdId1G0DLdB/2b1YjwK/jkZWsis28F5EpR 9yXoFgJbpAhWDw2LSXsuZIQZCMXXxp3IONGAXOqUBbU9GWhKRym05qOWcnolLzEkgdA8 PDtQsqE3q1Z4OWnlRJ5+0t2gLt+JOjxoUtFvUVeE668/bP3CdtF0oBn1TQYb43e68/b+ Gufw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728990411; x=1729595211; 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=sBrQ02u0x+gOef7QkcexjhixwvYLcPbk6l/zE/g/i1o=; b=Yxa7joIYvwpDUqPoSflZzSFy15GonT5mnMgU3tGRG9gIo/w99lVBAhYfa1kQNAD7ui C2k+FCSdwGTg4dsWm1yXDeYQ1N6BNgAtZ55kREybhzgxRBle/c/tnfLAfJiLdndfPqja PtuEO2xUC5PwFfG99f6zuJ9tYK6nz3rO+hQ8qhpW+94Q5T4G/8YvQ59HhkNGM8V8DpJX PSrP/5LBNogxOeGYVE7reuWI/+IYSkwcQvD3duF1OJhPCh/8q8GH2emr4o7up8fiGS2b dz2bMbOd/TloEDEYK4zjmvS44JFXF2EGzzMuzdj/9I3GZJbV740s3P9RtbhE9OyyKZmb Ff/A== X-Forwarded-Encrypted: i=1; AJvYcCUG1oVbGAIQgInSywtYlhYZgnkmQN9Nr8RxhPqXySplMiM8maR4LR9TnXoCTkqislirAOfTTXJWgc0=@vger.kernel.org, AJvYcCVlX5xuBowhOOGIqxGca6FY4W37rnuDhOD736ISO5dpt2p542ehY+4dzHgsfr9Felt5PFUv6WaVXUEzvFI=@vger.kernel.org, AJvYcCXLnr1eC4IgP8GcLCBkBC+EAqYIu183WPkz+q5vlizUiGn/8f+OYoh0hMZzHbxy+/3EowFkCRA4Ls93ww==@vger.kernel.org X-Gm-Message-State: AOJu0Yy9TEHasHmBH7j46ViEvPsEWkodhIzqN1K3g0wYGing/IqMEVYg vXrpwlj4W9HSj/L43OafcxjDjvo/YCsTLLgbNB0+IrXaAVnzBEwJOeqk0IWt X-Google-Smtp-Source: AGHT+IFTPY+YqfaloGUHhYaFV9LoEdK/S04iLUW4htdOHIlqQfxo5RikCRfVHmY660LYaFHowAsXHw== X-Received: by 2002:a05:600c:4e4f:b0:42c:b220:4769 with SMTP id 5b1f17b1804b1-431256167f0mr139921975e9.32.1728990411165; Tue, 15 Oct 2024 04:06:51 -0700 (PDT) Received: from localhost (host-79-18-120-72.retail.telecomitalia.it. [79.18.120.72]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4313f569943sm14423005e9.12.2024.10.15.04.06.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Oct 2024 04:06:50 -0700 (PDT) From: Matteo Martelli Date: Tue, 15 Oct 2024 13:06:36 +0200 Subject: [PATCH v3 3/5] iio: pac1921: use read_avail+release APIs instead of custom ext_info Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241015-iio-read-avail-release-v3-3-ac3e08f25cb3@gmail.com> References: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@gmail.com> In-Reply-To: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@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 The pac1921 driver was exposing the available scale info via an ad-hoc ext_info attribute instead of using the read_avail API. This to avoid a possible race condition: while the available current scales were being printed to sysfs by iio core (iio_read_channel_info_avail), the shunt resistor might have been changed concurrently. Switch to the read_avail+release APIs now that the race condition has been addressed. Signed-off-by: Matteo Martelli --- drivers/iio/adc/pac1921.c | 128 ++++++++++++++++--------------------------= ---- 1 file changed, 45 insertions(+), 83 deletions(-) diff --git a/drivers/iio/adc/pac1921.c b/drivers/iio/adc/pac1921.c index a96fae546bc1e6d1bf3a0dbe67204c191d77a3ee..f6f8f9122a78d1b5e63d8184203= eb3dae55eb560 100644 --- a/drivers/iio/adc/pac1921.c +++ b/drivers/iio/adc/pac1921.c @@ -444,11 +444,52 @@ static int pac1921_read_avail(struct iio_dev *indio_d= ev, *vals =3D pac1921_int_num_samples; *length =3D ARRAY_SIZE(pac1921_int_num_samples); return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_SCALE: + switch (chan->channel) { + case PAC1921_CHAN_VBUS: + *vals =3D (const int *)pac1921_vbus_scales; + *length =3D ARRAY_SIZE(pac1921_vbus_scales) * 2; + *type =3D IIO_VAL_INT_PLUS_NANO; + return IIO_AVAIL_LIST; + + case PAC1921_CHAN_VSENSE: + *vals =3D (const int *)pac1921_vsense_scales; + *length =3D ARRAY_SIZE(pac1921_vsense_scales) * 2; + *type =3D IIO_VAL_INT_PLUS_NANO; + return IIO_AVAIL_LIST; + + case PAC1921_CHAN_CURRENT: { + struct pac1921_priv *priv =3D iio_priv(indio_dev); + + *length =3D ARRAY_SIZE(priv->current_scales) * 2; + *type =3D IIO_VAL_INT_PLUS_NANO; + + guard(mutex)(&priv->lock); + + *vals =3D kmemdup_array((int *)priv->current_scales, + *length, sizeof(int), GFP_KERNEL); + if (!*vals) + return -ENOMEM; + + return IIO_AVAIL_LIST; + } + default: + return -EINVAL; + } default: return -EINVAL; } } =20 +static void pac1921_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + if (mask =3D=3D IIO_CHAN_INFO_SCALE && + chan->channel =3D=3D PAC1921_CHAN_CURRENT) + kfree(vals); +} + /* * Perform configuration update sequence: set the device into read state, = then * write the config register and set the device back into integration stat= e. @@ -748,6 +789,7 @@ static int pac1921_read_event_value(struct iio_dev *ind= io_dev, static const struct iio_info pac1921_iio =3D { .read_raw =3D pac1921_read_raw, .read_avail =3D pac1921_read_avail, + .read_avail_release_resource =3D pac1921_read_avail_release_res, .write_raw =3D pac1921_write_raw, .write_raw_get_fmt =3D pac1921_write_raw_get_fmt, .read_label =3D pac1921_read_label, @@ -805,88 +847,7 @@ static ssize_t pac1921_write_shunt_resistor(struct iio= _dev *indio_dev, return len; } =20 -/* - * Emit on sysfs the list of available scales contained in scales_tbl - * - * TODO:: this function can be replaced with iio_format_avail_list() if the - * latter will ever be exported. - * - * Must be called with lock held if the scales_tbl can change runtime (e.g= . for - * the current scales table) - */ -static ssize_t pac1921_format_scale_avail(const int (*const scales_tbl)[2], - size_t size, char *buf) -{ - ssize_t len =3D 0; - - for (unsigned int i =3D 0; i < size; i++) { - if (i !=3D 0) { - len +=3D sysfs_emit_at(buf, len, " "); - if (len >=3D PAGE_SIZE) - return -EFBIG; - } - len +=3D sysfs_emit_at(buf, len, "%d.%09d", scales_tbl[i][0], - scales_tbl[i][1]); - if (len >=3D PAGE_SIZE) - return -EFBIG; - } - - len +=3D sysfs_emit_at(buf, len, "\n"); - return len; -} - -/* - * Read available scales for a specific channel - * - * NOTE: using extended info insted of iio.read_avail() because access to - * current scales must be locked as they depend on shunt resistor which may - * change runtime. Caller of iio.read_avail() would access the table unloc= ked - * instead. - */ -static ssize_t pac1921_read_scale_avail(struct iio_dev *indio_dev, - uintptr_t private, - const struct iio_chan_spec *chan, - char *buf) -{ - struct pac1921_priv *priv =3D iio_priv(indio_dev); - const int (*scales_tbl)[2]; - size_t size; - - switch (chan->channel) { - case PAC1921_CHAN_VBUS: - scales_tbl =3D pac1921_vbus_scales; - size =3D ARRAY_SIZE(pac1921_vbus_scales); - return pac1921_format_scale_avail(scales_tbl, size, buf); - - case PAC1921_CHAN_VSENSE: - scales_tbl =3D pac1921_vsense_scales; - size =3D ARRAY_SIZE(pac1921_vsense_scales); - return pac1921_format_scale_avail(scales_tbl, size, buf); - - case PAC1921_CHAN_CURRENT: { - guard(mutex)(&priv->lock); - scales_tbl =3D priv->current_scales; - size =3D ARRAY_SIZE(priv->current_scales); - return pac1921_format_scale_avail(scales_tbl, size, buf); - } - default: - return -EINVAL; - } -} - -#define PAC1921_EXT_INFO_SCALE_AVAIL { \ - .name =3D "scale_available", \ - .read =3D pac1921_read_scale_avail, \ - .shared =3D IIO_SEPARATE, \ -} - -static const struct iio_chan_spec_ext_info pac1921_ext_info_voltage[] =3D { - PAC1921_EXT_INFO_SCALE_AVAIL, - {} -}; - static const struct iio_chan_spec_ext_info pac1921_ext_info_current[] =3D { - PAC1921_EXT_INFO_SCALE_AVAIL, { .name =3D "shunt_resistor", .read =3D pac1921_read_shunt_resistor, @@ -910,6 +871,7 @@ static const struct iio_chan_spec pac1921_channels[] = =3D { .type =3D IIO_VOLTAGE, .info_mask_separate =3D BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_separate_available =3D BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all =3D BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | BIT(IIO_CHAN_INFO_SAMP_FREQ), @@ -927,12 +889,12 @@ static const struct iio_chan_spec pac1921_channels[] = =3D { .indexed =3D 1, .event_spec =3D pac1921_overflow_event, .num_event_specs =3D ARRAY_SIZE(pac1921_overflow_event), - .ext_info =3D pac1921_ext_info_voltage, }, { .type =3D IIO_VOLTAGE, .info_mask_separate =3D BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_separate_available =3D BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all =3D BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | BIT(IIO_CHAN_INFO_SAMP_FREQ), @@ -950,12 +912,12 @@ static const struct iio_chan_spec pac1921_channels[] = =3D { .indexed =3D 1, .event_spec =3D pac1921_overflow_event, .num_event_specs =3D ARRAY_SIZE(pac1921_overflow_event), - .ext_info =3D pac1921_ext_info_voltage, }, { .type =3D IIO_CURRENT, .info_mask_separate =3D BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_separate_available =3D BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all =3D BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | BIT(IIO_CHAN_INFO_SAMP_FREQ), --=20 2.47.0 From nobody Wed Nov 27 00:24:38 2024 Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) (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 6674A1EABB3; Tue, 15 Oct 2024 11:06:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990416; cv=none; b=eoZ7UK622Rwd4HY571SXGi0PhxBaJY+kg04D/uubaxG8AU/JrDZ8JTV6ft2G2zcozrUWg32wTPW2UrzTdzCsRm0WQmgqq+MIuJWj0k+HkVceVnBwg2M43sMxUeMGHhSIi9nc7GaOMAIUSNLdfJ/rOKAc627jcZsCagS1J2XiehM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990416; c=relaxed/simple; bh=lLwcWxwjDNJi83wrQWAVlHlVnJucfvYmyQRif2fP9tA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=LwyqShea14UTcXC0Il3baxpxniUP5c6RaNWcODR29MNgVcOcw1Ey22flayfyzV/qn3V/n6JliSrm/ALCl2PO/yrKQbzoebYqm90uQZ9V+2tevxToVTLwl+5LIlAbWprQkMi/2wvSmZHseX4AZF45g8Xxi7xu93HRnpqN0UoZtiE= 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=ZdvpNqlX; arc=none smtp.client-ip=209.85.221.50 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="ZdvpNqlX" Received: by mail-wr1-f50.google.com with SMTP id ffacd0b85a97d-37d325beee2so3185121f8f.2; Tue, 15 Oct 2024 04:06:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728990412; x=1729595212; 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=ZdvpNqlXSpIQeqpRSbFlqd3CR6MDoc2Fr3TXLSzAhsxh8JvMJ19lvKNnJhCyyV6qqw TZfCiYG9zz8++mH3Re1Wv1VmugVeRclsu2BJ6/N6e9H9cig59To5kxFTj3cZsI5nBym3 gncgtyJyZgJT6vc1NYx6ozvFT0djw70qZ+JBbPU9eUb+Jma/dfyjPs71Wj5/ncMsVT23 y96nFhOOujSLviZFOz+2LhSXsbvg8WbXHMNrKMi6m0q3jsw3Tx1SULDxTzQEs/Rs+og1 bnwJnPBUZgyznl6zuuRnZEdm0zOlydcb/7QXF6d+l1pvp6qJ9Jq53U+9K9lzxL1XZHWT +WAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728990412; x=1729595212; 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=FmdGUBf20yhC1m7CCyRYe/fRoov05KFCcPiFJKmabaX+qHkeL5vJKx+zIJGyEn2j/U ixpPCb2UpLNGqzBt7gxCrfSgMww1JfYJ7hKphw06e6HIYspuYdAtUTPUgPAS26nGbRGv P5xlutxwiRskm4Tz7Suz8UEiPtMYlnRNL4ml5Nf9I5tRpLm470dgJZgV3/tmFDxb4eZp 8E5PojAWqLwggMd8u2TWRyciOTxI04tzHGT+IuOvujg3MsGFWamxrpW+6J0cHq8Nb7nt InThrv0iVN0sgxfMhp9KcAK2fTgsbsxeCnHyK7/MfF7goG7QaMwdb+etUO7uVd5P/sWC jvCA== X-Forwarded-Encrypted: i=1; AJvYcCUQnerg60fS3MgLPLV2cGbsl2C5SZEID67Ix/UUS8FtBTqxg2hP5dqreFEgMXw7ZLlST3Js6P5m4Lg=@vger.kernel.org, AJvYcCWjeFE57ji1FTUlBu9ukLntLI7dsQ7n7zlk9O2uhC7FKY7+0U7XQQ9kXT4AiMcTpvPaiX2meUc+TIDGIQ==@vger.kernel.org, AJvYcCXiigWTQMaAyZMdnD1MS6rlK4Y8QoCs51RArYXcYxCv6I2zAUMrlWcKGtq2oBOB6KsekZVVV517MJZgH5M=@vger.kernel.org X-Gm-Message-State: AOJu0Yx5KXmwPzZO8xFIpwYDX8z6cDWl8QOVP3oYA3+5t8OFt1DU1X5c IVvGLskEvSwh0CqEkp2WY4FrxASwykQfz1vhEfcky1ZgbXjiXYU1 X-Google-Smtp-Source: AGHT+IGimy5Up107eFlhSpVKC0Sm2j66ke58pEfclfBPpXVKCcjVZOm35BOwZtCXFrioz6OjXfgVNA== X-Received: by 2002:adf:ec92:0:b0:37d:4dcc:7fb4 with SMTP id ffacd0b85a97d-37d5fec8d04mr7811001f8f.10.1728990412396; Tue, 15 Oct 2024 04:06:52 -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-37d7fa7a118sm1304744f8f.4.2024.10.15.04.06.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Oct 2024 04:06:52 -0700 (PDT) From: Matteo Martelli Date: Tue, 15 Oct 2024 13:06:37 +0200 Subject: [PATCH v3 4/5] iio: ad7192: copy/release available filter frequencies to fix race Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241015-iio-read-avail-release-v3-4-ac3e08f25cb3@gmail.com> References: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@gmail.com> In-Reply-To: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@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..acf625ced0b21db8d44f77929e8= a875b3c10e1b1 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 =3D ARRAY_SIZE(st->scale_avail) * 2; =20 return IIO_AVAIL_LIST; - case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: - *vals =3D (int *)st->filter_freq_avail; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: { *type =3D IIO_VAL_FRACTIONAL; *length =3D ARRAY_SIZE(st->filter_freq_avail) * 2; =20 + guard(mutex)(&st->lock); + + *vals =3D 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 =3D (int *)st->oversampling_ratio_avail; *type =3D IIO_VAL_INT; @@ -1073,6 +1080,14 @@ static int ad7192_read_avail(struct iio_dev *indio_d= ev, return -EINVAL; } =20 +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 =3D=3D IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) + kfree(vals); +} + static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsign= ed long *scan_mask) { struct ad7192_state *st =3D iio_priv(indio_dev); @@ -1098,6 +1113,7 @@ static const struct iio_info ad7192_info =3D { .write_raw =3D ad7192_write_raw, .write_raw_get_fmt =3D ad7192_write_raw_get_fmt, .read_avail =3D ad7192_read_avail, + .read_avail_release_resource =3D ad7192_read_avail_release_res, .attrs =3D &ad7192_attribute_group, .validate_trigger =3D ad_sd_validate_trigger, .update_scan_mode =3D ad7192_update_scan_mode, @@ -1108,6 +1124,7 @@ static const struct iio_info ad7194_info =3D { .write_raw =3D ad7192_write_raw, .write_raw_get_fmt =3D ad7192_write_raw_get_fmt, .read_avail =3D ad7192_read_avail, + .read_avail_release_resource =3D ad7192_read_avail_release_res, .validate_trigger =3D ad_sd_validate_trigger, }; =20 @@ -1116,6 +1133,7 @@ static const struct iio_info ad7195_info =3D { .write_raw =3D ad7192_write_raw, .write_raw_get_fmt =3D ad7192_write_raw_get_fmt, .read_avail =3D ad7192_read_avail, + .read_avail_release_resource =3D ad7192_read_avail_release_res, .attrs =3D &ad7195_attribute_group, .validate_trigger =3D ad_sd_validate_trigger, .update_scan_mode =3D ad7192_update_scan_mode, --=20 2.47.0 From nobody Wed Nov 27 00:24:38 2024 Received: from mail-wm1-f51.google.com (mail-wm1-f51.google.com [209.85.128.51]) (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 608751EBA0B; Tue, 15 Oct 2024 11:06:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990417; cv=none; b=ZuiDD2ndDgwztnMuaF8WZkV4P9HjbXsuKdMK3aYevQ2O4Wf3jRX+PrP4ugWYqRM4xtwFS4NBSWy7qcjWORSI+eJW/qqfYsPGMmrHBFf8VGjeY3Wgz5D9dpdFXtPioE6U4N0VrT9yUujX3jqi5RGhePW+yfjNs/pcPNxSY81J0oU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728990417; c=relaxed/simple; bh=zPhyRDG9F+zgzh0+HIEmtXBb7OQBzROgLZ7mJASXsvQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=GAeLNbKzK+90R0rOOqCWvmGLjHBkrqf8Oj93yEuBHbh96f59yDp9zYoLIrybFBY2UHneEnOvHgk2plpPwZCALmKtBjlerfoJPAEPNNmuY2PBfhkO6lamiyrbuYPy8wWgioJSKVnLc/tDDsZ93fTmhaWsOsT/LO4dlnmHgNuMoFA= 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=AFSkbutG; arc=none smtp.client-ip=209.85.128.51 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="AFSkbutG" Received: by mail-wm1-f51.google.com with SMTP id 5b1f17b1804b1-430576ff251so45679815e9.0; Tue, 15 Oct 2024 04:06:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728990414; x=1729595214; 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=Yg5C99O5lFsD3GMjKIKiUiVjWoF4T1zlBP/PbUaocsA=; b=AFSkbutG0edBJinqvX3i2EInMETdxjTZImq/9HnTG9GAXnonnmNMKcdQThG2O8kxaf RhCpcDCxfIcWLDJaNwtSOEyXEp1bNuGcpRIn2NTHoYiikQ7+4uolBSOj59nZ2Xdi8HvQ 4Eh6INlypp0UIwlOd1GPDsH/EUP8jFXEe8HIa9i2udzdp45lxuRSyOHdrr9pLhgtMtLV pkw1w3sTJw4bEXqFNJ2pn216L07Rqh2Q7nvVgpDy/8tbzdV5Z/QGo38fgFsQUluXdaBr tqR/x8ThOWyXP2y3PPKwsYM9KJ5TEGh49fVwVnl5vKS8XtA6f4piNmB4gvdjEnEtWj3s RakA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728990414; x=1729595214; 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=Yg5C99O5lFsD3GMjKIKiUiVjWoF4T1zlBP/PbUaocsA=; b=eYkjUOP4o2JPjuW8/QvBdnnaR2juZj1bdEz5QX7e84BU3kpPGCm/1Wy+EJK7bxjnKr k2gHaDvk58WG6uLEqp6f08vXPKXCVaeQMEvNdyKJUDGLjx9+rwwlo/6KQRpcSPdONJMc jFPVvihcFB6PgNmFMXUpRKc/3xJOFO2F6u1syEAkBkvor6SGam7cnHDUXG+IHEzQQWo/ 4WkpJbb+UZePa0pIRNk1QExWgJUpIlwItHymBIMBlFPfVADMLOzLkdrvYVA5L7u+YjID d0Avl0+CddXj8FKXt3F6ivefivfVk00iX4jtttx2tPyxfSJx8vzbqM2g4v0mDE6Ht9e+ vVaw== X-Forwarded-Encrypted: i=1; AJvYcCVUMWRy3rXVtYwrOw/ck9Caw1SDg71YAwpJROT0eisovofPJ4JH5X6zci1NoIc3t+uU0PydMGbuZxNuiB4=@vger.kernel.org, AJvYcCVl6nQc/BR2N1ldXUzxluFlLl2Zyn+f42+eanTYuOKyufuH7llrAu7/zOn3j5AkkCZkx5pTBH3LXntEJQ==@vger.kernel.org, AJvYcCW6ya1iBRnyq+28fQMWgM+sYNumDSKlMIksF5+R35jk/3Pyl/9Iw4QOk4gFxsj4HVKyOrmBWfYR5c0=@vger.kernel.org X-Gm-Message-State: AOJu0YzuYY7yXvPakMxu+BIl/bxd88Trj0wTtgqjiOHikPdb765FGku/ +Q692S0RaAb3Mr3qcco+ehPQYFJlBjGyl6claBxaR+tHgarvgbkA X-Google-Smtp-Source: AGHT+IG60MSlabhsrBA6bEZ2PUeFwZkstarjm4Ih1FAL5vlJRowBO16QYUrs13k4ISoJBISPOpLwkA== X-Received: by 2002:a05:600c:4e8a:b0:42c:af06:718 with SMTP id 5b1f17b1804b1-4311df435e7mr136981645e9.28.1728990413655; Tue, 15 Oct 2024 04:06:53 -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-37d7fa7a10dsm1289181f8f.2.2024.10.15.04.06.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Oct 2024 04:06:53 -0700 (PDT) From: Matteo Martelli Date: Tue, 15 Oct 2024 13:06:38 +0200 Subject: [PATCH v3 5/5] iio: as73211: copy/release available integration times to fix race Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241015-iio-read-avail-release-v3-5-ac3e08f25cb3@gmail.com> References: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@gmail.com> In-Reply-To: <20241015-iio-read-avail-release-v3-0-ac3e08f25cb3@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 integration times 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 integration times buffer and free it in the read_avail_release_resource callback. Signed-off-by: Matteo Martelli --- drivers/iio/light/as73211.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/drivers/iio/light/as73211.c b/drivers/iio/light/as73211.c index be0068081ebbbb37fdfb252b67a77b302ff725f6..c4c94873e6a1cc926cfb724d906= b07222773c43f 100644 --- a/drivers/iio/light/as73211.c +++ b/drivers/iio/light/as73211.c @@ -108,7 +108,8 @@ struct as73211_spec_dev_data { * @creg1: Cached Configuration Register 1. * @creg2: Cached Configuration Register 2. * @creg3: Cached Configuration Register 3. - * @mutex: Keeps cached registers in sync with the device. + * @mutex: Keeps cached registers in sync with the device and protects + * int_time_avail concurrent access for updating and reading. * @completion: Completion to wait for interrupt. * @int_time_avail: Available integration times (depend on sampling freque= ncy). * @spec_dev: device-specific configuration. @@ -493,17 +494,32 @@ static int as73211_read_avail(struct iio_dev *indio_d= ev, struct iio_chan_spec co *type =3D IIO_VAL_INT; return IIO_AVAIL_LIST; =20 - case IIO_CHAN_INFO_INT_TIME: + case IIO_CHAN_INFO_INT_TIME: { *length =3D ARRAY_SIZE(data->int_time_avail); - *vals =3D data->int_time_avail; *type =3D IIO_VAL_INT_PLUS_MICRO; - return IIO_AVAIL_LIST; =20 + guard(mutex)(&data->mutex); + + *vals =3D kmemdup_array(data->int_time_avail, *length, + sizeof(int), GFP_KERNEL); + if (!*vals) + return -ENOMEM; + + return IIO_AVAIL_LIST; + } default: return -EINVAL; } } =20 +static void as73211_read_avail_release_res(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask) +{ + if (mask =3D=3D IIO_CHAN_INFO_INT_TIME) + kfree(vals); +} + static int _as73211_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan __always_unused, int val, int val2, long mask) @@ -699,6 +715,7 @@ static irqreturn_t as73211_trigger_handler(int irq __al= ways_unused, void *p) static const struct iio_info as73211_info =3D { .read_raw =3D as73211_read_raw, .read_avail =3D as73211_read_avail, + .read_avail_release_resource =3D as73211_read_avail_release_res, .write_raw =3D as73211_write_raw, }; =20 --=20 2.47.0