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From:   James Clark <james.clark@arm.com>
To:     linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org
Cc:     linux@roeck-us.net, michal.simek@amd.com,
        Jonathan.Cameron@huawei.com, James Clark <james.clark@arm.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Jean Delvare <jdelvare@suse.com>,
        Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>,
        Jonathan Cameron <jic23@kernel.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Jiri Slaby <jirislaby@kernel.org>, linux-doc@vger.kernel.org,
        linux-hwmon@vger.kernel.org, linux-iio@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org
Subject: [PATCH v4 1/4] devres: Provide krealloc_array
Date:   Tue,  9 May 2023 10:49:38 +0100
Message-Id: <20230509094942.396150-2-james.clark@arm.com>
In-Reply-To: <20230509094942.396150-1-james.clark@arm.com>
References: <20230509094942.396150-1-james.clark@arm.com>
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There is no krealloc_array equivalent in devres. Users would have to
do their own multiplication overflow check so provide one.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
---
 Documentation/driver-api/driver-model/devres.rst |  1 +
 include/linux/device.h                           | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 4249eb4239e0..8be086b3f829 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -364,6 +364,7 @@ MEM
   devm_kmalloc_array()
   devm_kmemdup()
   devm_krealloc()
+  devm_krealloc_array()
   devm_kstrdup()
   devm_kstrdup_const()
   devm_kvasprintf()
diff --git a/include/linux/device.h b/include/linux/device.h
index 472dd24d4823..58f4f5948edb 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -223,6 +223,17 @@ static inline void *devm_kcalloc(struct device *dev,
 {
 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 }
+static inline __realloc_size(3, 4) void * __must_check
+devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
+		return NULL;
+
+	return devm_krealloc(dev, p, bytes, flags);
+}
+
 void devm_kfree(struct device *dev, const void *p);
 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
-- 
2.34.1