[PATCH v3 0/2] lib/string_helpers: Introduce tokenize_user_input()

[PATCH v3 0/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

Continuation of recent upstream discussion [1] regarding user string
tokenization.

First, tokenize_user_input() is introduced to allow for splitting
specified user string into a sequence of integers. Makes use of
get_options() internally so the parsing logic is not duplicated.

With that done, redundant parts of the sound driver are removed.

Originally similar functionality was added for the SOF sound driver. As
more users are on the horizon, it is desirable to update existing
string_helpers code and provide a unified solution.


Changes in v3:
- relocated tokenize_user_input() implementation to string_helpers as
  requested by Matthew

Changes in v2:
- reused get_options() so no parsing logic is duplicated
- simplified __user variant with help of memdup_user_nul()
  Both suggested by Andy, thanks for thourough review


[1]: https://lore.kernel.org/alsa-devel/20220707091301.1282291-1-cezary.rojewski@intel.com/


Cezary Rojewski (2):
  lib/string_helpers: Introduce tokenize_user_input()
  ASoC: SOF: Remove strsplit_u32() and tokenize_input()

 include/linux/string_helpers.h    |  2 +
 lib/string_helpers.c              | 45 +++++++++++++++
 sound/soc/sof/sof-client-probes.c | 93 ++++---------------------------
 3 files changed, 59 insertions(+), 81 deletions(-)

-- 
2.25.1

[PATCH v3 0/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

Continuation of recent upstream discussion [1] regarding user string
tokenization.

First, tokenize_user_input() is introduced to allow for splitting
specified user string into a sequence of integers. Makes use of
get_options() internally so the parsing logic is not duplicated.

With that done, redundant parts of the sound driver are removed.

Originally similar functionality was added for the SOF sound driver. As
more users are on the horizon, it is desirable to update existing
string_helpers code and provide a unified solution.


Changes in v3:
- relocated tokenize_user_input() implementation to string_helpers as
  requested by Matthew

Changes in v2:
- reused get_options() so no parsing logic is duplicated
- simplified __user variant with help of memdup_user_nul()
  Both suggested by Andy, thanks for thourough review


[1]: https://lore.kernel.org/alsa-devel/20220707091301.1282291-1-cezary.rojewski@intel.com/


Cezary Rojewski (2):
  lib/string_helpers: Introduce tokenize_user_input()
  ASoC: SOF: Remove strsplit_u32() and tokenize_input()

 include/linux/string_helpers.h    |  2 +
 lib/string_helpers.c              | 45 +++++++++++++++
 sound/soc/sof/sof-client-probes.c | 93 ++++---------------------------
 3 files changed, 59 insertions(+), 81 deletions(-)

-- 
2.25.1

[PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

Add new helper function to allow for splitting specified user string
into a sequence of integers. Internally it makes use of get_options() so
the returned sequence contains the integers extracted plus an additional
element that begins the sequence and specifies the integers count.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 include/linux/string_helpers.h |  2 ++
 lib/string_helpers.c           | 45 ++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h
index 4d72258d42fd..97583dae556f 100644
--- a/include/linux/string_helpers.h
+++ b/include/linux/string_helpers.h
@@ -21,6 +21,8 @@ enum string_size_units {
 void string_get_size(u64 size, u64 blk_size, enum string_size_units units,
 		     char *buf, int len);
 
+int tokenize_user_input(const char __user *from, size_t count, int **tkns);
+
 #define UNESCAPE_SPACE		BIT(0)
 #define UNESCAPE_OCTAL		BIT(1)
 #define UNESCAPE_HEX		BIT(2)
diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 5ed3beb066e6..f878afccab4c 100644
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -131,6 +131,51 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units,
 }
 EXPORT_SYMBOL(string_get_size);
 
+/**
+ * tokenize_user_input - Split string into a sequence of integers
+ * @from:	The user space buffer to read from
+ * @ppos:	The current position in the buffer
+ * @count:	The maximum number of bytes to read
+ * @tkns:	Returned pointer to sequence of integers
+ *
+ * On success @tkns is allocated and initialized with a sequence of
+ * integers extracted from the @from plus an additional element that
+ * begins the sequence and specifies the integers count.
+ *
+ * Caller takes responsibility for freeing @tkns when it is no longer
+ * needed.
+ */
+int tokenize_user_input(const char __user *from, size_t count, int **tkns)
+{
+	int *ints, nints;
+	char *buf;
+	int ret = 0;
+
+	buf = memdup_user_nul(from, count);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	get_options(buf, 0, &nints);
+	if (!nints) {
+		ret = -ENOENT;
+		goto free_buf;
+	}
+
+	ints = kcalloc(nints + 1, sizeof(*ints), GFP_KERNEL);
+	if (!ints) {
+		ret = -ENOMEM;
+		goto free_buf;
+	}
+
+	get_options(buf, nints + 1, ints);
+	*tkns = ints;
+
+free_buf:
+	kfree(buf);
+	return ret;
+}
+EXPORT_SYMBOL(tokenize_user_input);
+
 static bool unescape_space(char **src, char **dst)
 {
 	char *p = *dst, *q = *src;
-- 
2.25.1

[PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

Add new helper function to allow for splitting specified user string
into a sequence of integers. Internally it makes use of get_options() so
the returned sequence contains the integers extracted plus an additional
element that begins the sequence and specifies the integers count.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 include/linux/string_helpers.h |  2 ++
 lib/string_helpers.c           | 45 ++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h
index 4d72258d42fd..97583dae556f 100644
--- a/include/linux/string_helpers.h
+++ b/include/linux/string_helpers.h
@@ -21,6 +21,8 @@ enum string_size_units {
 void string_get_size(u64 size, u64 blk_size, enum string_size_units units,
 		     char *buf, int len);
 
+int tokenize_user_input(const char __user *from, size_t count, int **tkns);
+
 #define UNESCAPE_SPACE		BIT(0)
 #define UNESCAPE_OCTAL		BIT(1)
 #define UNESCAPE_HEX		BIT(2)
diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 5ed3beb066e6..f878afccab4c 100644
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -131,6 +131,51 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units,
 }
 EXPORT_SYMBOL(string_get_size);
 
+/**
+ * tokenize_user_input - Split string into a sequence of integers
+ * @from:	The user space buffer to read from
+ * @ppos:	The current position in the buffer
+ * @count:	The maximum number of bytes to read
+ * @tkns:	Returned pointer to sequence of integers
+ *
+ * On success @tkns is allocated and initialized with a sequence of
+ * integers extracted from the @from plus an additional element that
+ * begins the sequence and specifies the integers count.
+ *
+ * Caller takes responsibility for freeing @tkns when it is no longer
+ * needed.
+ */
+int tokenize_user_input(const char __user *from, size_t count, int **tkns)
+{
+	int *ints, nints;
+	char *buf;
+	int ret = 0;
+
+	buf = memdup_user_nul(from, count);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	get_options(buf, 0, &nints);
+	if (!nints) {
+		ret = -ENOENT;
+		goto free_buf;
+	}
+
+	ints = kcalloc(nints + 1, sizeof(*ints), GFP_KERNEL);
+	if (!ints) {
+		ret = -ENOMEM;
+		goto free_buf;
+	}
+
+	get_options(buf, nints + 1, ints);
+	*tkns = ints;
+
+free_buf:
+	kfree(buf);
+	return ret;
+}
+EXPORT_SYMBOL(tokenize_user_input);
+
 static bool unescape_space(char **src, char **dst)
 {
 	char *p = *dst, *q = *src;
-- 
2.25.1

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Andy Shevchenko]

On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
>
> Add new helper function to allow for splitting specified user string
> into a sequence of integers. Internally it makes use of get_options() so
> the returned sequence contains the integers extracted plus an additional
> element that begins the sequence and specifies the integers count.

Thanks! In general it looks good to me, but a few minor comments below.

...

> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);

Not sure how I can deduct from the name what function is actually
doing. Suggested new name: int_array_parse_user().

int int_array_parse_user(const char __user *from, size_t count, int **array);

(Note that we have _user suffix for many APIs in the kernel that does
interact with user space memory)

...

> + * @tkns:      Returned pointer to sequence of integers

array

...

If you are okay with this, you may add my
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Andy Shevchenko]

On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
>
> Add new helper function to allow for splitting specified user string
> into a sequence of integers. Internally it makes use of get_options() so
> the returned sequence contains the integers extracted plus an additional
> element that begins the sequence and specifies the integers count.

Thanks! In general it looks good to me, but a few minor comments below.

...

> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);

Not sure how I can deduct from the name what function is actually
doing. Suggested new name: int_array_parse_user().

int int_array_parse_user(const char __user *from, size_t count, int **array);

(Note that we have _user suffix for many APIs in the kernel that does
interact with user space memory)

...

> + * @tkns:      Returned pointer to sequence of integers

array

...

If you are okay with this, you may add my
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

On 2022-09-01 9:34 PM, Andy Shevchenko wrote:
> On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> <cezary.rojewski@intel.com> wrote:

...

>> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);
> 
> Not sure how I can deduct from the name what function is actually
> doing. Suggested new name: int_array_parse_user().
> 
> int int_array_parse_user(const char __user *from, size_t count, int **array);
> 
> (Note that we have _user suffix for many APIs in the kernel that does
> interact with user space memory)


That's why I've added '_user_' in the middle! Anyway, I guess the 
expectation is that it's a suffix - precisely at the end of the name.

Could we reorder it a bit: "parse_int_array_user"?

>> + * @tkns:      Returned pointer to sequence of integers
> 
> array

Ack.

> If you are okay with this, you may add my
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Cezary Rojewski]

On 2022-09-01 9:34 PM, Andy Shevchenko wrote:
> On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> <cezary.rojewski@intel.com> wrote:

...

>> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);
> 
> Not sure how I can deduct from the name what function is actually
> doing. Suggested new name: int_array_parse_user().
> 
> int int_array_parse_user(const char __user *from, size_t count, int **array);
> 
> (Note that we have _user suffix for many APIs in the kernel that does
> interact with user space memory)


That's why I've added '_user_' in the middle! Anyway, I guess the 
expectation is that it's a suffix - precisely at the end of the name.

Could we reorder it a bit: "parse_int_array_user"?

>> + * @tkns:      Returned pointer to sequence of integers
> 
> array

Ack.

> If you are okay with this, you may add my
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Andy Shevchenko]

On Fri, Sep 2, 2022 at 10:46 AM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
> On 2022-09-01 9:34 PM, Andy Shevchenko wrote:
> > On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> > <cezary.rojewski@intel.com> wrote:

...

> >> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);
> >
> > Not sure how I can deduct from the name what function is actually
> > doing. Suggested new name: int_array_parse_user().
> >
> > int int_array_parse_user(const char __user *from, size_t count, int **array);
> >
> > (Note that we have _user suffix for many APIs in the kernel that does
> > interact with user space memory)
>
> That's why I've added '_user_' in the middle! Anyway, I guess the
> expectation is that it's a suffix - precisely at the end of the name.
>
> Could we reorder it a bit: "parse_int_array_user"?

Most of the exported functions that have 'parse' word, have it after
namespace, but in this case there is no dedicated namespace and it
also will be in alignment with parse_options_str. That said, go for
it.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[Andy Shevchenko]

On Fri, Sep 2, 2022 at 10:46 AM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
> On 2022-09-01 9:34 PM, Andy Shevchenko wrote:
> > On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> > <cezary.rojewski@intel.com> wrote:

...

> >> +int tokenize_user_input(const char __user *from, size_t count, int **tkns);
> >
> > Not sure how I can deduct from the name what function is actually
> > doing. Suggested new name: int_array_parse_user().
> >
> > int int_array_parse_user(const char __user *from, size_t count, int **array);
> >
> > (Note that we have _user suffix for many APIs in the kernel that does
> > interact with user space memory)
>
> That's why I've added '_user_' in the middle! Anyway, I guess the
> expectation is that it's a suffix - precisely at the end of the name.
>
> Could we reorder it a bit: "parse_int_array_user"?

Most of the exported functions that have 'parse' word, have it after
namespace, but in this case there is no dedicated namespace and it
also will be in alignment with parse_options_str. That said, go for
it.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Cezary Rojewski]

Make use of global user input tokenization helper instead of the
internal one as both serve same purpose. With that, both strsplit_u32()
and tokenize_input() become unused so remove them.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 sound/soc/sof/sof-client-probes.c | 93 ++++---------------------------
 1 file changed, 12 insertions(+), 81 deletions(-)

diff --git a/sound/soc/sof/sof-client-probes.c b/sound/soc/sof/sof-client-probes.c
index eb246b823461..e9c44831fae1 100644
--- a/sound/soc/sof/sof-client-probes.c
+++ b/sound/soc/sof/sof-client-probes.c
@@ -12,6 +12,7 @@
 #include <linux/debugfs.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/string_helpers.h>
 #include <sound/soc.h>
 #include <sound/sof/header.h>
 #include "sof-client.h"
@@ -410,79 +411,6 @@ static const struct snd_compress_ops sof_probes_compressed_ops = {
 	.copy = sof_probes_compr_copy,
 };
 
-/**
- * strsplit_u32 - Split string into sequence of u32 tokens
- * @buf:	String to split into tokens.
- * @delim:	String containing delimiter characters.
- * @tkns:	Returned u32 sequence pointer.
- * @num_tkns:	Returned number of tokens obtained.
- */
-static int strsplit_u32(char *buf, const char *delim, u32 **tkns, size_t *num_tkns)
-{
-	char *s;
-	u32 *data, *tmp;
-	size_t count = 0;
-	size_t cap = 32;
-	int ret = 0;
-
-	*tkns = NULL;
-	*num_tkns = 0;
-	data = kcalloc(cap, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	while ((s = strsep(&buf, delim)) != NULL) {
-		ret = kstrtouint(s, 0, data + count);
-		if (ret)
-			goto exit;
-		if (++count >= cap) {
-			cap *= 2;
-			tmp = krealloc(data, cap * sizeof(*data), GFP_KERNEL);
-			if (!tmp) {
-				ret = -ENOMEM;
-				goto exit;
-			}
-			data = tmp;
-		}
-	}
-
-	if (!count)
-		goto exit;
-	*tkns = kmemdup(data, count * sizeof(*data), GFP_KERNEL);
-	if (!(*tkns)) {
-		ret = -ENOMEM;
-		goto exit;
-	}
-	*num_tkns = count;
-
-exit:
-	kfree(data);
-	return ret;
-}
-
-static int tokenize_input(const char __user *from, size_t count,
-			  loff_t *ppos, u32 **tkns, size_t *num_tkns)
-{
-	char *buf;
-	int ret;
-
-	buf = kmalloc(count + 1, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	ret = simple_write_to_buffer(buf, count, ppos, from, count);
-	if (ret != count) {
-		ret = ret >= 0 ? -EIO : ret;
-		goto exit;
-	}
-
-	buf[count] = '\0';
-	ret = strsplit_u32(buf, ",", tkns, num_tkns);
-exit:
-	kfree(buf);
-	return ret;
-}
-
 static ssize_t sof_probes_dfs_points_read(struct file *file, char __user *to,
 					  size_t count, loff_t *ppos)
 {
@@ -548,8 +476,8 @@ sof_probes_dfs_points_write(struct file *file, const char __user *from,
 	struct sof_probes_priv *priv = cdev->data;
 	struct device *dev = &cdev->auxdev.dev;
 	struct sof_probe_point_desc *desc;
-	size_t num_tkns, bytes;
-	u32 *tkns;
+	size_t bytes;
+	u32 num_tkns, *tkns;
 	int ret, err;
 
 	if (priv->extractor_stream_tag == SOF_PROBES_INVALID_NODE_ID) {
@@ -557,16 +485,18 @@ sof_probes_dfs_points_write(struct file *file, const char __user *from,
 		return -ENOENT;
 	}
 
-	ret = tokenize_input(from, count, ppos, &tkns, &num_tkns);
+	ret = tokenize_user_input(from, count, (int **)&tkns);
 	if (ret < 0)
 		return ret;
+
+	num_tkns = *tkns;
 	bytes = sizeof(*tkns) * num_tkns;
 	if (!num_tkns || (bytes % sizeof(*desc))) {
 		ret = -EINVAL;
 		goto exit;
 	}
 
-	desc = (struct sof_probe_point_desc *)tkns;
+	desc = (struct sof_probe_point_desc *)&tkns[1];
 
 	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0 && ret != -EACCES) {
@@ -603,8 +533,7 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 	struct sof_client_dev *cdev = file->private_data;
 	struct sof_probes_priv *priv = cdev->data;
 	struct device *dev = &cdev->auxdev.dev;
-	size_t num_tkns;
-	u32 *tkns;
+	u32 num_tkns, *tkns;
 	int ret, err;
 
 	if (priv->extractor_stream_tag == SOF_PROBES_INVALID_NODE_ID) {
@@ -612,9 +541,11 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 		return -ENOENT;
 	}
 
-	ret = tokenize_input(from, count, ppos, &tkns, &num_tkns);
+	ret = tokenize_user_input(from, count, (int **)&tkns);
 	if (ret < 0)
 		return ret;
+
+	num_tkns = *tkns;
 	if (!num_tkns) {
 		ret = -EINVAL;
 		goto exit;
@@ -626,7 +557,7 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 		goto exit;
 	}
 
-	ret = sof_probes_points_remove(cdev, tkns, num_tkns);
+	ret = sof_probes_points_remove(cdev, &tkns[1], num_tkns);
 	if (!ret)
 		ret = count;
 
-- 
2.25.1

[PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Cezary Rojewski]

Make use of global user input tokenization helper instead of the
internal one as both serve same purpose. With that, both strsplit_u32()
and tokenize_input() become unused so remove them.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 sound/soc/sof/sof-client-probes.c | 93 ++++---------------------------
 1 file changed, 12 insertions(+), 81 deletions(-)

diff --git a/sound/soc/sof/sof-client-probes.c b/sound/soc/sof/sof-client-probes.c
index eb246b823461..e9c44831fae1 100644
--- a/sound/soc/sof/sof-client-probes.c
+++ b/sound/soc/sof/sof-client-probes.c
@@ -12,6 +12,7 @@
 #include <linux/debugfs.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/string_helpers.h>
 #include <sound/soc.h>
 #include <sound/sof/header.h>
 #include "sof-client.h"
@@ -410,79 +411,6 @@ static const struct snd_compress_ops sof_probes_compressed_ops = {
 	.copy = sof_probes_compr_copy,
 };
 
-/**
- * strsplit_u32 - Split string into sequence of u32 tokens
- * @buf:	String to split into tokens.
- * @delim:	String containing delimiter characters.
- * @tkns:	Returned u32 sequence pointer.
- * @num_tkns:	Returned number of tokens obtained.
- */
-static int strsplit_u32(char *buf, const char *delim, u32 **tkns, size_t *num_tkns)
-{
-	char *s;
-	u32 *data, *tmp;
-	size_t count = 0;
-	size_t cap = 32;
-	int ret = 0;
-
-	*tkns = NULL;
-	*num_tkns = 0;
-	data = kcalloc(cap, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	while ((s = strsep(&buf, delim)) != NULL) {
-		ret = kstrtouint(s, 0, data + count);
-		if (ret)
-			goto exit;
-		if (++count >= cap) {
-			cap *= 2;
-			tmp = krealloc(data, cap * sizeof(*data), GFP_KERNEL);
-			if (!tmp) {
-				ret = -ENOMEM;
-				goto exit;
-			}
-			data = tmp;
-		}
-	}
-
-	if (!count)
-		goto exit;
-	*tkns = kmemdup(data, count * sizeof(*data), GFP_KERNEL);
-	if (!(*tkns)) {
-		ret = -ENOMEM;
-		goto exit;
-	}
-	*num_tkns = count;
-
-exit:
-	kfree(data);
-	return ret;
-}
-
-static int tokenize_input(const char __user *from, size_t count,
-			  loff_t *ppos, u32 **tkns, size_t *num_tkns)
-{
-	char *buf;
-	int ret;
-
-	buf = kmalloc(count + 1, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	ret = simple_write_to_buffer(buf, count, ppos, from, count);
-	if (ret != count) {
-		ret = ret >= 0 ? -EIO : ret;
-		goto exit;
-	}
-
-	buf[count] = '\0';
-	ret = strsplit_u32(buf, ",", tkns, num_tkns);
-exit:
-	kfree(buf);
-	return ret;
-}
-
 static ssize_t sof_probes_dfs_points_read(struct file *file, char __user *to,
 					  size_t count, loff_t *ppos)
 {
@@ -548,8 +476,8 @@ sof_probes_dfs_points_write(struct file *file, const char __user *from,
 	struct sof_probes_priv *priv = cdev->data;
 	struct device *dev = &cdev->auxdev.dev;
 	struct sof_probe_point_desc *desc;
-	size_t num_tkns, bytes;
-	u32 *tkns;
+	size_t bytes;
+	u32 num_tkns, *tkns;
 	int ret, err;
 
 	if (priv->extractor_stream_tag == SOF_PROBES_INVALID_NODE_ID) {
@@ -557,16 +485,18 @@ sof_probes_dfs_points_write(struct file *file, const char __user *from,
 		return -ENOENT;
 	}
 
-	ret = tokenize_input(from, count, ppos, &tkns, &num_tkns);
+	ret = tokenize_user_input(from, count, (int **)&tkns);
 	if (ret < 0)
 		return ret;
+
+	num_tkns = *tkns;
 	bytes = sizeof(*tkns) * num_tkns;
 	if (!num_tkns || (bytes % sizeof(*desc))) {
 		ret = -EINVAL;
 		goto exit;
 	}
 
-	desc = (struct sof_probe_point_desc *)tkns;
+	desc = (struct sof_probe_point_desc *)&tkns[1];
 
 	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0 && ret != -EACCES) {
@@ -603,8 +533,7 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 	struct sof_client_dev *cdev = file->private_data;
 	struct sof_probes_priv *priv = cdev->data;
 	struct device *dev = &cdev->auxdev.dev;
-	size_t num_tkns;
-	u32 *tkns;
+	u32 num_tkns, *tkns;
 	int ret, err;
 
 	if (priv->extractor_stream_tag == SOF_PROBES_INVALID_NODE_ID) {
@@ -612,9 +541,11 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 		return -ENOENT;
 	}
 
-	ret = tokenize_input(from, count, ppos, &tkns, &num_tkns);
+	ret = tokenize_user_input(from, count, (int **)&tkns);
 	if (ret < 0)
 		return ret;
+
+	num_tkns = *tkns;
 	if (!num_tkns) {
 		ret = -EINVAL;
 		goto exit;
@@ -626,7 +557,7 @@ sof_probes_dfs_points_remove_write(struct file *file, const char __user *from,
 		goto exit;
 	}
 
-	ret = sof_probes_points_remove(cdev, tkns, num_tkns);
+	ret = sof_probes_points_remove(cdev, &tkns[1], num_tkns);
 	if (!ret)
 		ret = count;
 
-- 
2.25.1

Re: [PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Andy Shevchenko]

On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
>
> Make use of global user input tokenization helper instead of the
> internal one as both serve same purpose. With that, both strsplit_u32()

the same

> and tokenize_input() become unused so remove them.

...

>  #include <linux/debugfs.h>
>  #include <linux/module.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/string_helpers.h>

I believe either blank line needs to be here (to split the sound / SOF
group of headers) or this should be put after 'so*'-ones

>  #include <sound/soc.h>
>  #include <sound/sof/header.h>
>  #include "sof-client.h"

...

>         struct sof_probes_priv *priv = cdev->data;
>         struct device *dev = &cdev->auxdev.dev;
>         struct sof_probe_point_desc *desc;
> -       size_t num_tkns, bytes;
> -       u32 *tkns;
> +       size_t bytes;
> +       u32 num_tkns, *tkns;

I would expect a longer line first.

>         int ret, err;

...

With the above addressed
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Andy Shevchenko]

On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
<cezary.rojewski@intel.com> wrote:
>
> Make use of global user input tokenization helper instead of the
> internal one as both serve same purpose. With that, both strsplit_u32()

the same

> and tokenize_input() become unused so remove them.

...

>  #include <linux/debugfs.h>
>  #include <linux/module.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/string_helpers.h>

I believe either blank line needs to be here (to split the sound / SOF
group of headers) or this should be put after 'so*'-ones

>  #include <sound/soc.h>
>  #include <sound/sof/header.h>
>  #include "sof-client.h"

...

>         struct sof_probes_priv *priv = cdev->data;
>         struct device *dev = &cdev->auxdev.dev;
>         struct sof_probe_point_desc *desc;
> -       size_t num_tkns, bytes;
> -       u32 *tkns;
> +       size_t bytes;
> +       u32 num_tkns, *tkns;

I would expect a longer line first.

>         int ret, err;

...

With the above addressed
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Cezary Rojewski]

On 2022-09-01 9:38 PM, Andy Shevchenko wrote:
> On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> <cezary.rojewski@intel.com> wrote:
>>
>> Make use of global user input tokenization helper instead of the
>> internal one as both serve same purpose. With that, both strsplit_u32()
> 
> the same
> 
>> and tokenize_input() become unused so remove them.

...

>>   #include <linux/debugfs.h>
>>   #include <linux/module.h>
>>   #include <linux/pm_runtime.h>
>> +#include <linux/string_helpers.h>
> 
> I believe either blank line needs to be here (to split the sound / SOF
> group of headers) or this should be put after 'so*'-ones

Newline it is then.

>>   #include <sound/soc.h>
>>   #include <sound/sof/header.h>
>>   #include "sof-client.h"

...

>>          struct sof_probes_priv *priv = cdev->data;
>>          struct device *dev = &cdev->auxdev.dev;
>>          struct sof_probe_point_desc *desc;
>> -       size_t num_tkns, bytes;
>> -       u32 *tkns;
>> +       size_t bytes;
>> +       u32 num_tkns, *tkns;
> 
> I would expect a longer line first.

Ack.


> With the above addressed
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 

Re: [PATCH v3 2/2] ASoC: SOF: Remove strsplit_u32() and tokenize_input()

[Cezary Rojewski]

On 2022-09-01 9:38 PM, Andy Shevchenko wrote:
> On Thu, Sep 1, 2022 at 8:40 PM Cezary Rojewski
> <cezary.rojewski@intel.com> wrote:
>>
>> Make use of global user input tokenization helper instead of the
>> internal one as both serve same purpose. With that, both strsplit_u32()
> 
> the same
> 
>> and tokenize_input() become unused so remove them.

...

>>   #include <linux/debugfs.h>
>>   #include <linux/module.h>
>>   #include <linux/pm_runtime.h>
>> +#include <linux/string_helpers.h>
> 
> I believe either blank line needs to be here (to split the sound / SOF
> group of headers) or this should be put after 'so*'-ones

Newline it is then.

>>   #include <sound/soc.h>
>>   #include <sound/sof/header.h>
>>   #include "sof-client.h"

...

>>          struct sof_probes_priv *priv = cdev->data;
>>          struct device *dev = &cdev->auxdev.dev;
>>          struct sof_probe_point_desc *desc;
>> -       size_t num_tkns, bytes;
>> -       u32 *tkns;
>> +       size_t bytes;
>> +       u32 num_tkns, *tkns;
> 
> I would expect a longer line first.

Ack.


> With the above addressed
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 

Re: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input()

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 6770 bytes --]

:::::: 
:::::: Manual check reason: "low confidence bisect report"
:::::: Manual check reason: "low confidence static check warning: lib/string_helpers.c:150:20: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]"
:::::: 

BCC: lkp(a)intel.com
CC: kbuild-all(a)lists.01.org
In-Reply-To: <20220901175022.334824-2-cezary.rojewski@intel.com>
References: <20220901175022.334824-2-cezary.rojewski@intel.com>
TO: Cezary Rojewski <cezary.rojewski@intel.com>
TO: alsa-devel(a)alsa-project.org
TO: broonie(a)kernel.org
CC: andy(a)kernel.org
CC: Cezary Rojewski <cezary.rojewski@intel.com>
CC: kai.vehmanen(a)linux.intel.com
CC: yung-chuan.liao(a)linux.intel.com
CC: tiwai(a)suse.com
CC: pierre-louis.bossart(a)linux.intel.com
CC: willy(a)infradead.org
CC: lgirdwood(a)gmail.com
CC: hdegoede(a)redhat.com
CC: Andy Shevchenko <andy.shevchenko@gmail.com>
CC: ranjani.sridharan(a)linux.intel.com
CC: amadeuszx.slawinski(a)linux.intel.com
CC: peter.ujfalusi(a)linux.intel.com
CC: linux-kernel(a)vger.kernel.org

Hi Cezary,

I love your patch! Perhaps something to improve:

[auto build test WARNING on broonie-sound/for-next]
[also build test WARNING on linus/master v6.0-rc3]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Cezary-Rojewski/lib-string_helpers-Introduce-tokenize_user_input/20220902-014254
base:   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next
:::::: branch date: 27 hours ago
:::::: commit date: 27 hours ago
config: arm-randconfig-c002-20220901 (https://download.01.org/0day-ci/archive/20220903/202209030411.0HeReNTd-lkp(a)intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/53e2025c60da991b4e879aaf336a6635c0b87b07
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Cezary-Rojewski/lib-string_helpers-Introduce-tokenize_user_input/20220902-014254
        git checkout 53e2025c60da991b4e879aaf336a6635c0b87b07
        # save the config file
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross ARCH=arm KBUILD_USERCFLAGS='-fanalyzer -Wno-error' 

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

gcc_analyzer warnings: (new ones prefixed by >>)
   lib/string_helpers.c: In function 'tokenize_user_input':
>> lib/string_helpers.c:150:20: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
     150 |         int *ints, nints;
         |                    ^~~~~
     'tokenize_user_input': event 1
       |
       |  150 |         int *ints, nints;
       |      |                    ^~~~~
       |      |                    |
       |      |                    (1) use of uninitialized value '<unknown>' here
       |

vim +150 lib/string_helpers.c

16c7fa05829e8b9 Andy Shevchenko 2013-04-30  133  
53e2025c60da991 Cezary Rojewski 2022-09-01  134  /**
53e2025c60da991 Cezary Rojewski 2022-09-01  135   * tokenize_user_input - Split string into a sequence of integers
53e2025c60da991 Cezary Rojewski 2022-09-01  136   * @from:	The user space buffer to read from
53e2025c60da991 Cezary Rojewski 2022-09-01  137   * @ppos:	The current position in the buffer
53e2025c60da991 Cezary Rojewski 2022-09-01  138   * @count:	The maximum number of bytes to read
53e2025c60da991 Cezary Rojewski 2022-09-01  139   * @tkns:	Returned pointer to sequence of integers
53e2025c60da991 Cezary Rojewski 2022-09-01  140   *
53e2025c60da991 Cezary Rojewski 2022-09-01  141   * On success @tkns is allocated and initialized with a sequence of
53e2025c60da991 Cezary Rojewski 2022-09-01  142   * integers extracted from the @from plus an additional element that
53e2025c60da991 Cezary Rojewski 2022-09-01  143   * begins the sequence and specifies the integers count.
53e2025c60da991 Cezary Rojewski 2022-09-01  144   *
53e2025c60da991 Cezary Rojewski 2022-09-01  145   * Caller takes responsibility for freeing @tkns when it is no longer
53e2025c60da991 Cezary Rojewski 2022-09-01  146   * needed.
53e2025c60da991 Cezary Rojewski 2022-09-01  147   */
53e2025c60da991 Cezary Rojewski 2022-09-01  148  int tokenize_user_input(const char __user *from, size_t count, int **tkns)
53e2025c60da991 Cezary Rojewski 2022-09-01  149  {
53e2025c60da991 Cezary Rojewski 2022-09-01 @150  	int *ints, nints;
53e2025c60da991 Cezary Rojewski 2022-09-01  151  	char *buf;
53e2025c60da991 Cezary Rojewski 2022-09-01  152  	int ret = 0;
53e2025c60da991 Cezary Rojewski 2022-09-01  153  
53e2025c60da991 Cezary Rojewski 2022-09-01  154  	buf = memdup_user_nul(from, count);
53e2025c60da991 Cezary Rojewski 2022-09-01  155  	if (IS_ERR(buf))
53e2025c60da991 Cezary Rojewski 2022-09-01  156  		return PTR_ERR(buf);
53e2025c60da991 Cezary Rojewski 2022-09-01  157  
53e2025c60da991 Cezary Rojewski 2022-09-01  158  	get_options(buf, 0, &nints);
53e2025c60da991 Cezary Rojewski 2022-09-01  159  	if (!nints) {
53e2025c60da991 Cezary Rojewski 2022-09-01  160  		ret = -ENOENT;
53e2025c60da991 Cezary Rojewski 2022-09-01  161  		goto free_buf;
53e2025c60da991 Cezary Rojewski 2022-09-01  162  	}
53e2025c60da991 Cezary Rojewski 2022-09-01  163  
53e2025c60da991 Cezary Rojewski 2022-09-01  164  	ints = kcalloc(nints + 1, sizeof(*ints), GFP_KERNEL);
53e2025c60da991 Cezary Rojewski 2022-09-01  165  	if (!ints) {
53e2025c60da991 Cezary Rojewski 2022-09-01  166  		ret = -ENOMEM;
53e2025c60da991 Cezary Rojewski 2022-09-01  167  		goto free_buf;
53e2025c60da991 Cezary Rojewski 2022-09-01  168  	}
53e2025c60da991 Cezary Rojewski 2022-09-01  169  
53e2025c60da991 Cezary Rojewski 2022-09-01  170  	get_options(buf, nints + 1, ints);
53e2025c60da991 Cezary Rojewski 2022-09-01  171  	*tkns = ints;
53e2025c60da991 Cezary Rojewski 2022-09-01  172  
53e2025c60da991 Cezary Rojewski 2022-09-01  173  free_buf:
53e2025c60da991 Cezary Rojewski 2022-09-01  174  	kfree(buf);
53e2025c60da991 Cezary Rojewski 2022-09-01  175  	return ret;
53e2025c60da991 Cezary Rojewski 2022-09-01  176  }
53e2025c60da991 Cezary Rojewski 2022-09-01  177  EXPORT_SYMBOL(tokenize_user_input);
53e2025c60da991 Cezary Rojewski 2022-09-01  178  

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp