[PATCH 2/5] gpu: drm: amdgpu: Replace snprintf() with sysfs_emit()

From: Sumera Priyadarsini <sylphrenadin@gmail.com>
To: dri-devel@lists.freedesktop.org
Cc: outreachy-kernel@googlegroups.com, alexander.deucher@amd.com,
	christian.koenig@amd.com, airlied@linux.ie, daniel@ffwll.ch,
	melissa.srw@gmail.com, linux-media@vger.kernel.org,
	amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/5] gpu: drm: amdgpu: Replace snprintf() with sysfs_emit()
Date: Thu, 22 Oct 2020 19:13:11 +0530	[thread overview]
Message-ID: <78546ad9343ddf1b0f8bc300a3c8ae9a0dcb0ef9.1603371258.git.sylphrenadin@gmail.com> (raw)
In-Reply-To: <cover.1603371258.git.sylphrenadin@gmail.com>

Using snprintf() for show() methods holds the risk of buffer overrun
as snprintf() does not know the PAGE_SIZE maximum of the temporary
buffer used to output sysfs content.

Modify amdgpu_device.c to use sysfs_emit() instead which knows the
size of the temporary buffer.

Issue found with Coccinelle.

Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index f7307af76452..7eef6b20578f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -135,7 +135,7 @@ static ssize_t amdgpu_device_get_pcie_replay_count(struct device *dev,
 	struct amdgpu_device *adev = drm_to_adev(ddev);
 	uint64_t cnt = amdgpu_asic_get_pcie_replay_count(adev);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", cnt);
+	return sysfs_emit(buf, PAGE_SIZE, "%llu\n", cnt);
 }
 
 static DEVICE_ATTR(pcie_replay_count, S_IRUGO,
@@ -159,7 +159,7 @@ static ssize_t amdgpu_device_get_product_name(struct device *dev,
 	struct drm_device *ddev = dev_get_drvdata(dev);
 	struct amdgpu_device *adev = drm_to_adev(ddev);
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", adev->product_name);
+	return sysfs_emit(buf, PAGE_SIZE, "%s\n", adev->product_name);
 }
 
 static DEVICE_ATTR(product_name, S_IRUGO,
@@ -181,7 +181,7 @@ static ssize_t amdgpu_device_get_product_number(struct device *dev,
 	struct drm_device *ddev = dev_get_drvdata(dev);
 	struct amdgpu_device *adev = drm_to_adev(ddev);
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", adev->product_number);
+	return sysfs_emit(buf, PAGE_SIZE, "%s\n", adev->product_number);
 }
 
 static DEVICE_ATTR(product_number, S_IRUGO,
@@ -203,7 +203,7 @@ static ssize_t amdgpu_device_get_serial_number(struct device *dev,
 	struct drm_device *ddev = dev_get_drvdata(dev);
 	struct amdgpu_device *adev = drm_to_adev(ddev);
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", adev->serial);
+	return sysfs_emit(buf, PAGE_SIZE, "%s\n", adev->serial);
 }
 
 static DEVICE_ATTR(serial_number, S_IRUGO,
-- 
2.25.1

