* [PATCH] drm/amdgpu/pm: Remove VLA usage
@ 2018-06-20 18:26 Kees Cook
2018-07-17 3:59 ` Kees Cook
0 siblings, 1 reply; 2+ messages in thread
From: Kees Cook @ 2018-06-20 18:26 UTC (permalink / raw)
To: Alex Deucher
Cc: linux-kernel, Christian König, David (ChunMing) Zhou,
David Airlie, Rex Zhu, Huang Rui, Felix Kuehling, amd-gfx,
dri-devel
In the quest to remove all stack VLA usage from the kernel[1], this
uses the maximum sane buffer size and removes copy/paste code.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 100 +++++++++++--------------
1 file changed, 42 insertions(+), 58 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
index b455da487782..5eb98cde22ed 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
@@ -593,40 +593,59 @@ static ssize_t amdgpu_get_pp_dpm_sclk(struct device *dev,
return snprintf(buf, PAGE_SIZE, "\n");
}
-static ssize_t amdgpu_set_pp_dpm_sclk(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t count)
+/*
+ * Worst case: 32 bits individually specified, in octal at 12 characters
+ * per line (+1 for \n).
+ */
+#define AMDGPU_MASK_BUF_MAX (32 * 13)
+
+static ssize_t amdgpu_read_mask(const char *buf, size_t count, uint32_t *mask)
{
- struct drm_device *ddev = dev_get_drvdata(dev);
- struct amdgpu_device *adev = ddev->dev_private;
int ret;
long level;
- uint32_t mask = 0;
char *sub_str = NULL;
char *tmp;
- char buf_cpy[count];
+ char buf_cpy[AMDGPU_MASK_BUF_MAX + 1];
const char delimiter[3] = {' ', '\n', '\0'};
+ size_t bytes;
- memcpy(buf_cpy, buf, count+1);
+ *mask = 0;
+
+ bytes = min(count, sizeof(buf_cpy) - 1);
+ memcpy(buf_cpy, buf, bytes);
+ buf_cpy[bytes] = '\0';
tmp = buf_cpy;
while (tmp[0]) {
- sub_str = strsep(&tmp, delimiter);
+ sub_str = strsep(&tmp, delimiter);
if (strlen(sub_str)) {
ret = kstrtol(sub_str, 0, &level);
-
- if (ret) {
- count = -EINVAL;
- goto fail;
- }
- mask |= 1 << level;
+ if (ret)
+ return -EINVAL;
+ *mask |= 1 << level;
} else
break;
}
+
+ return 0;
+}
+
+static ssize_t amdgpu_set_pp_dpm_sclk(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct drm_device *ddev = dev_get_drvdata(dev);
+ struct amdgpu_device *adev = ddev->dev_private;
+ int ret;
+ uint32_t mask = 0;
+
+ ret = amdgpu_read_mask(buf, count, &mask);
+ if (ret)
+ return ret;
+
if (adev->powerplay.pp_funcs->force_clock_level)
amdgpu_dpm_force_clock_level(adev, PP_SCLK, mask);
-fail:
return count;
}
@@ -651,32 +670,15 @@ static ssize_t amdgpu_set_pp_dpm_mclk(struct device *dev,
struct drm_device *ddev = dev_get_drvdata(dev);
struct amdgpu_device *adev = ddev->dev_private;
int ret;
- long level;
uint32_t mask = 0;
- char *sub_str = NULL;
- char *tmp;
- char buf_cpy[count];
- const char delimiter[3] = {' ', '\n', '\0'};
- memcpy(buf_cpy, buf, count+1);
- tmp = buf_cpy;
- while (tmp[0]) {
- sub_str = strsep(&tmp, delimiter);
- if (strlen(sub_str)) {
- ret = kstrtol(sub_str, 0, &level);
+ ret = amdgpu_read_mask(buf, count, &mask);
+ if (ret)
+ return ret;
- if (ret) {
- count = -EINVAL;
- goto fail;
- }
- mask |= 1 << level;
- } else
- break;
- }
if (adev->powerplay.pp_funcs->force_clock_level)
amdgpu_dpm_force_clock_level(adev, PP_MCLK, mask);
-fail:
return count;
}
@@ -701,33 +703,15 @@ static ssize_t amdgpu_set_pp_dpm_pcie(struct device *dev,
struct drm_device *ddev = dev_get_drvdata(dev);
struct amdgpu_device *adev = ddev->dev_private;
int ret;
- long level;
uint32_t mask = 0;
- char *sub_str = NULL;
- char *tmp;
- char buf_cpy[count];
- const char delimiter[3] = {' ', '\n', '\0'};
-
- memcpy(buf_cpy, buf, count+1);
- tmp = buf_cpy;
- while (tmp[0]) {
- sub_str = strsep(&tmp, delimiter);
- if (strlen(sub_str)) {
- ret = kstrtol(sub_str, 0, &level);
+ ret = amdgpu_read_mask(buf, count, &mask);
+ if (ret)
+ return ret;
- if (ret) {
- count = -EINVAL;
- goto fail;
- }
- mask |= 1 << level;
- } else
- break;
- }
if (adev->powerplay.pp_funcs->force_clock_level)
amdgpu_dpm_force_clock_level(adev, PP_PCIE, mask);
-fail:
return count;
}
--
2.17.1
--
Kees Cook
Pixel Security
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] drm/amdgpu/pm: Remove VLA usage
2018-06-20 18:26 [PATCH] drm/amdgpu/pm: Remove VLA usage Kees Cook
@ 2018-07-17 3:59 ` Kees Cook
0 siblings, 0 replies; 2+ messages in thread
From: Kees Cook @ 2018-07-17 3:59 UTC (permalink / raw)
To: Alex Deucher
Cc: LKML, Christian König, David (ChunMing) Zhou, David Airlie,
Rex Zhu, Huang Rui, Felix Kuehling, amd-gfx list,
Maling list - DRI developers
On Wed, Jun 20, 2018 at 11:26 AM, Kees Cook <keescook@chromium.org> wrote:
> In the quest to remove all stack VLA usage from the kernel[1], this
> uses the maximum sane buffer size and removes copy/paste code.
>
> [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
Friendly ping! Who's tree should this go through?
Thanks!
-Kees
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 100 +++++++++++--------------
> 1 file changed, 42 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> index b455da487782..5eb98cde22ed 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> @@ -593,40 +593,59 @@ static ssize_t amdgpu_get_pp_dpm_sclk(struct device *dev,
> return snprintf(buf, PAGE_SIZE, "\n");
> }
>
> -static ssize_t amdgpu_set_pp_dpm_sclk(struct device *dev,
> - struct device_attribute *attr,
> - const char *buf,
> - size_t count)
> +/*
> + * Worst case: 32 bits individually specified, in octal at 12 characters
> + * per line (+1 for \n).
> + */
> +#define AMDGPU_MASK_BUF_MAX (32 * 13)
> +
> +static ssize_t amdgpu_read_mask(const char *buf, size_t count, uint32_t *mask)
> {
> - struct drm_device *ddev = dev_get_drvdata(dev);
> - struct amdgpu_device *adev = ddev->dev_private;
> int ret;
> long level;
> - uint32_t mask = 0;
> char *sub_str = NULL;
> char *tmp;
> - char buf_cpy[count];
> + char buf_cpy[AMDGPU_MASK_BUF_MAX + 1];
> const char delimiter[3] = {' ', '\n', '\0'};
> + size_t bytes;
>
> - memcpy(buf_cpy, buf, count+1);
> + *mask = 0;
> +
> + bytes = min(count, sizeof(buf_cpy) - 1);
> + memcpy(buf_cpy, buf, bytes);
> + buf_cpy[bytes] = '\0';
> tmp = buf_cpy;
> while (tmp[0]) {
> - sub_str = strsep(&tmp, delimiter);
> + sub_str = strsep(&tmp, delimiter);
> if (strlen(sub_str)) {
> ret = kstrtol(sub_str, 0, &level);
> -
> - if (ret) {
> - count = -EINVAL;
> - goto fail;
> - }
> - mask |= 1 << level;
> + if (ret)
> + return -EINVAL;
> + *mask |= 1 << level;
> } else
> break;
> }
> +
> + return 0;
> +}
> +
> +static ssize_t amdgpu_set_pp_dpm_sclk(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf,
> + size_t count)
> +{
> + struct drm_device *ddev = dev_get_drvdata(dev);
> + struct amdgpu_device *adev = ddev->dev_private;
> + int ret;
> + uint32_t mask = 0;
> +
> + ret = amdgpu_read_mask(buf, count, &mask);
> + if (ret)
> + return ret;
> +
> if (adev->powerplay.pp_funcs->force_clock_level)
> amdgpu_dpm_force_clock_level(adev, PP_SCLK, mask);
>
> -fail:
> return count;
> }
>
> @@ -651,32 +670,15 @@ static ssize_t amdgpu_set_pp_dpm_mclk(struct device *dev,
> struct drm_device *ddev = dev_get_drvdata(dev);
> struct amdgpu_device *adev = ddev->dev_private;
> int ret;
> - long level;
> uint32_t mask = 0;
> - char *sub_str = NULL;
> - char *tmp;
> - char buf_cpy[count];
> - const char delimiter[3] = {' ', '\n', '\0'};
>
> - memcpy(buf_cpy, buf, count+1);
> - tmp = buf_cpy;
> - while (tmp[0]) {
> - sub_str = strsep(&tmp, delimiter);
> - if (strlen(sub_str)) {
> - ret = kstrtol(sub_str, 0, &level);
> + ret = amdgpu_read_mask(buf, count, &mask);
> + if (ret)
> + return ret;
>
> - if (ret) {
> - count = -EINVAL;
> - goto fail;
> - }
> - mask |= 1 << level;
> - } else
> - break;
> - }
> if (adev->powerplay.pp_funcs->force_clock_level)
> amdgpu_dpm_force_clock_level(adev, PP_MCLK, mask);
>
> -fail:
> return count;
> }
>
> @@ -701,33 +703,15 @@ static ssize_t amdgpu_set_pp_dpm_pcie(struct device *dev,
> struct drm_device *ddev = dev_get_drvdata(dev);
> struct amdgpu_device *adev = ddev->dev_private;
> int ret;
> - long level;
> uint32_t mask = 0;
> - char *sub_str = NULL;
> - char *tmp;
> - char buf_cpy[count];
> - const char delimiter[3] = {' ', '\n', '\0'};
> -
> - memcpy(buf_cpy, buf, count+1);
> - tmp = buf_cpy;
>
> - while (tmp[0]) {
> - sub_str = strsep(&tmp, delimiter);
> - if (strlen(sub_str)) {
> - ret = kstrtol(sub_str, 0, &level);
> + ret = amdgpu_read_mask(buf, count, &mask);
> + if (ret)
> + return ret;
>
> - if (ret) {
> - count = -EINVAL;
> - goto fail;
> - }
> - mask |= 1 << level;
> - } else
> - break;
> - }
> if (adev->powerplay.pp_funcs->force_clock_level)
> amdgpu_dpm_force_clock_level(adev, PP_PCIE, mask);
>
> -fail:
> return count;
> }
>
> --
> 2.17.1
>
>
> --
> Kees Cook
> Pixel Security
--
Kees Cook
Pixel Security
^ permalink raw reply [flat|nested] 2+ messages in thread
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