[PATCH v4 0/5] lib: rework bitmap_parselist and tests

[PATCH v4 0/5] lib: rework bitmap_parselist and tests

[Yury Norov]

bitmap_parselist has been evolved from a pretty simple idea for long and
now lacks for refactoring. It is not structured, has nested loops and a
set of opaque-named variables.

Things are more complicated because bitmap_parselist() is a part of user
interface, and its behavior should not change.

In this patchset
 - bitmap_parselist_user() made a wrapper on bitmap_parselist();
 - bitmap_parselist() reworked (patch 2);
 - time measurement in test_bitmap_parselist switched to ktime_get
   (patch 3);
 - new tests introduced (patch 4), and
 - bitmap_parselist_user() testing enabled with the same testset as
   bitmap_parselist() (patch 5).

v1: https://lkml.org/lkml/2018/12/23/50
v2: https://www.spinics.net/lists/kernel/msg3048976.html
v3: https://lkml.org/lkml/2019/4/3/68
v4: - use handy memdup_user_nul() instead of copy_from_user() in patch 1;
    - comments indentation fixed.


Yury Norov (5):
  lib: make bitmap_parselist_user() a wrapper on bitmap_parselist()
  lib: rework bitmap_parselist
  lib/test_bitmap: switch test_bitmap_parselist to ktime_get()
  lib/test_bitmap: add testcases for bitmap_parselist
  lib/test_bitmap: add tests for bitmap_parselist_user

 lib/bitmap.c      | 277 ++++++++++++++++++++++++++--------------------
 lib/test_bitmap.c |  67 ++++++++---
 2 files changed, 210 insertions(+), 134 deletions(-)

-- 
2.17.1

[PATCH 1/5] lib: make bitmap_parselist_user() a wrapper on bitmap_parselist()

[Yury Norov]

Currently we parse user data byte after byte which leads to
overcomplification of parsing algorithm. The only user of
bitmap_parselist_user() is not performance-critical, and so we
can duplicate user data to kernel buffer and simply call
bitmap_parselist(). This rework lets us unify and simplify
bitmap_parselist() and bitmap_parselist_user(), which is done
in the following patch.

Signed-off-by: Yury Norov <ynorov@marvell.com>
---
 lib/bitmap.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 98872e9025da..79ed5538617b 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -632,19 +632,22 @@ EXPORT_SYMBOL(bitmap_parselist);
  * @nmaskbits: size of bitmap, in bits.
  *
  * Wrapper for bitmap_parselist(), providing it with user buffer.
- *
- * We cannot have this as an inline function in bitmap.h because it needs
- * linux/uaccess.h to get the access_ok() declaration and this causes
- * cyclic dependencies.
  */
 int bitmap_parselist_user(const char __user *ubuf,
 			unsigned int ulen, unsigned long *maskp,
 			int nmaskbits)
 {
-	if (!access_ok(ubuf, ulen))
-		return -EFAULT;
-	return __bitmap_parselist((const char __force *)ubuf,
-					ulen, 1, maskp, nmaskbits);
+	char *buf;
+	int ret;
+
+	buf = memdup_user_nul(ubuf, ulen);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	ret = bitmap_parselist(buf, maskp, nmaskbits);
+
+	kfree(buf);
+	return ret;
 }
 EXPORT_SYMBOL(bitmap_parselist_user);
 
-- 
2.17.1

Re: [PATCH 1/5] lib: make bitmap_parselist_user() a wrapper on bitmap_parselist()

[Andy Shevchenko]

On Fri, Apr 05, 2019 at 08:32:07PM +0300, Yury Norov wrote:
> Currently we parse user data byte after byte which leads to
> overcomplification of parsing algorithm. The only user of
> bitmap_parselist_user() is not performance-critical, and so we
> can duplicate user data to kernel buffer and simply call
> bitmap_parselist(). This rework lets us unify and simplify
> bitmap_parselist() and bitmap_parselist_user(), which is done
> in the following patch.
> 

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> Signed-off-by: Yury Norov <ynorov@marvell.com>
> ---
>  lib/bitmap.c | 19 +++++++++++--------
>  1 file changed, 11 insertions(+), 8 deletions(-)
> 
> diff --git a/lib/bitmap.c b/lib/bitmap.c
> index 98872e9025da..79ed5538617b 100644
> --- a/lib/bitmap.c
> +++ b/lib/bitmap.c
> @@ -632,19 +632,22 @@ EXPORT_SYMBOL(bitmap_parselist);
>   * @nmaskbits: size of bitmap, in bits.
>   *
>   * Wrapper for bitmap_parselist(), providing it with user buffer.
> - *
> - * We cannot have this as an inline function in bitmap.h because it needs
> - * linux/uaccess.h to get the access_ok() declaration and this causes
> - * cyclic dependencies.
>   */
>  int bitmap_parselist_user(const char __user *ubuf,
>  			unsigned int ulen, unsigned long *maskp,
>  			int nmaskbits)
>  {
> -	if (!access_ok(ubuf, ulen))
> -		return -EFAULT;
> -	return __bitmap_parselist((const char __force *)ubuf,
> -					ulen, 1, maskp, nmaskbits);
> +	char *buf;
> +	int ret;
> +
> +	buf = memdup_user_nul(ubuf, ulen);
> +	if (IS_ERR(buf))
> +		return PTR_ERR(buf);
> +
> +	ret = bitmap_parselist(buf, maskp, nmaskbits);
> +
> +	kfree(buf);
> +	return ret;
>  }
>  EXPORT_SYMBOL(bitmap_parselist_user);
>  
> -- 
> 2.17.1
> 

-- 
With Best Regards,
Andy Shevchenko

[PATCH 2/5] lib: rework bitmap_parselist

[Yury Norov]

Remove __bitmap_parselist helper and split the function to logical
parts.

Signed-off-by: Yury Norov <ynorov@marvell.com>
---
 lib/bitmap.c | 258 +++++++++++++++++++++++++++++----------------------
 1 file changed, 145 insertions(+), 113 deletions(-)

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 79ed5538617b..28e17b71f72f 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -477,12 +477,133 @@ int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
 }
 EXPORT_SYMBOL(bitmap_print_to_pagebuf);
 
+/*
+ * Region 9-38:4/10 describes the following bitmap structure:
+ * 0	   9  12    18			38
+ * .........****......****......****......
+ *	    ^  ^     ^			 ^
+ *      start  off   group_len	       end
+ */
+struct region {
+	unsigned int start;
+	unsigned int off;
+	unsigned int group_len;
+	unsigned int end;
+};
+
+static int bitmap_set_region(const struct region *r,
+				unsigned long *bitmap, int nbits)
+{
+	unsigned int start;
+
+	if (r->end >= nbits)
+		return -ERANGE;
+
+	for (start = r->start; start <= r->end; start += r->group_len)
+		bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
+
+	return 0;
+}
+
+static int bitmap_check_region(const struct region *r)
+{
+	if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const char *bitmap_getnum(const char *str, unsigned int *num)
+{
+	unsigned int n = 0, _num = 0;
+
+	if (!isdigit(*str))
+		return ERR_PTR(-EINVAL);
+
+	for (; isdigit(*str); str++) {
+		_num = _num * 10 + (*str - '0');
+		if (_num < n)
+			return ERR_PTR(-EOVERFLOW);
+
+		n = _num;
+	}
+
+	*num = _num;
+
+	return str;
+}
+
+static inline bool end_of_str(char c)
+{
+	return c == '\0' || c == '\n';
+}
+
+static inline bool __end_of_region(char c)
+{
+	return isspace(c) || c == ',';
+}
+
+static inline bool end_of_region(char c)
+{
+	return __end_of_region(c) || end_of_str(c);
+}
+
+/*
+ * The format allows commas and whitespases at the beginning
+ * of the region.
+ */
+static const char *bitmap_find_region(const char *str)
+{
+	while (__end_of_region(*str))
+		str++;
+
+	return end_of_str(*str) ? NULL : str;
+}
+
+static const char *bitmap_parse_region(const char *str, struct region *r)
+{
+	str = bitmap_getnum(str, &r->start);
+	if (IS_ERR(str))
+		return str;
+
+	if (end_of_region(*str))
+		goto no_end;
+
+	if (*str != '-')
+		return ERR_PTR(-EINVAL);
+
+	str = bitmap_getnum(str + 1, &r->end);
+	if (IS_ERR(str))
+		return str;
+
+	if (end_of_region(*str))
+		goto no_pattern;
+
+	if (*str != ':')
+		return ERR_PTR(-EINVAL);
+
+	str = bitmap_getnum(str + 1, &r->off);
+	if (IS_ERR(str))
+		return str;
+
+	if (*str != '/')
+		return ERR_PTR(-EINVAL);
+
+	return bitmap_getnum(str + 1, &r->group_len);
+
+no_end:
+	r->end = r->start;
+no_pattern:
+	r->off = r->end + 1;
+	r->group_len = r->end + 1;
+
+	return end_of_str(*str) ? NULL : str;
+}
+
 /**
- * __bitmap_parselist - convert list format ASCII string to bitmap
- * @buf: read nul-terminated user string from this buffer
- * @buflen: buffer size in bytes.  If string is smaller than this
- *    then it must be terminated with a \0.
- * @is_user: location of buffer, 0 indicates kernel space
+ * bitmap_parselist - convert list format ASCII string to bitmap
+ * @buf: read user string from this buffer; must be terminated
+ *    with a \0 or \n.
  * @maskp: write resulting mask here
  * @nmaskbits: number of bits in mask to be written
  *
@@ -498,127 +619,38 @@ EXPORT_SYMBOL(bitmap_print_to_pagebuf);
  *
  * Returns: 0 on success, -errno on invalid input strings. Error values:
  *
- *   - ``-EINVAL``: second number in range smaller than first
+ *   - ``-EINVAL``: wrong region format
  *   - ``-EINVAL``: invalid character in string
  *   - ``-ERANGE``: bit number specified too large for mask
+ *   - ``-EOVERFLOW``: integer overflow in the input parameters
  */
-static int __bitmap_parselist(const char *buf, unsigned int buflen,
-		int is_user, unsigned long *maskp,
-		int nmaskbits)
+int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
 {
-	unsigned int a, b, old_a, old_b;
-	unsigned int group_size, used_size, off;
-	int c, old_c, totaldigits, ndigits;
-	const char __user __force *ubuf = (const char __user __force *)buf;
-	int at_start, in_range, in_partial_range;
+	struct region r;
+	long ret;
 
-	totaldigits = c = 0;
-	old_a = old_b = 0;
-	group_size = used_size = 0;
 	bitmap_zero(maskp, nmaskbits);
-	do {
-		at_start = 1;
-		in_range = 0;
-		in_partial_range = 0;
-		a = b = 0;
-		ndigits = totaldigits;
 
-		/* Get the next cpu# or a range of cpu#'s */
-		while (buflen) {
-			old_c = c;
-			if (is_user) {
-				if (__get_user(c, ubuf++))
-					return -EFAULT;
-			} else
-				c = *buf++;
-			buflen--;
-			if (isspace(c))
-				continue;
-
-			/* A '\0' or a ',' signal the end of a cpu# or range */
-			if (c == '\0' || c == ',')
-				break;
-			/*
-			* whitespaces between digits are not allowed,
-			* but it's ok if whitespaces are on head or tail.
-			* when old_c is whilespace,
-			* if totaldigits == ndigits, whitespace is on head.
-			* if whitespace is on tail, it should not run here.
-			* as c was ',' or '\0',
-			* the last code line has broken the current loop.
-			*/
-			if ((totaldigits != ndigits) && isspace(old_c))
-				return -EINVAL;
-
-			if (c == '/') {
-				used_size = a;
-				at_start = 1;
-				in_range = 0;
-				a = b = 0;
-				continue;
-			}
+	while (buf) {
+		buf = bitmap_find_region(buf);
+		if (buf == NULL)
+			return 0;
 
-			if (c == ':') {
-				old_a = a;
-				old_b = b;
-				at_start = 1;
-				in_range = 0;
-				in_partial_range = 1;
-				a = b = 0;
-				continue;
-			}
+		buf = bitmap_parse_region(buf, &r);
+		if (IS_ERR(buf))
+			return PTR_ERR(buf);
 
-			if (c == '-') {
-				if (at_start || in_range)
-					return -EINVAL;
-				b = 0;
-				in_range = 1;
-				at_start = 1;
-				continue;
-			}
+		ret = bitmap_check_region(&r);
+		if (ret)
+			return ret;
 
-			if (!isdigit(c))
-				return -EINVAL;
+		ret = bitmap_set_region(&r, maskp, nmaskbits);
+		if (ret)
+			return ret;
+	}
 
-			b = b * 10 + (c - '0');
-			if (!in_range)
-				a = b;
-			at_start = 0;
-			totaldigits++;
-		}
-		if (ndigits == totaldigits)
-			continue;
-		if (in_partial_range) {
-			group_size = a;
-			a = old_a;
-			b = old_b;
-			old_a = old_b = 0;
-		} else {
-			used_size = group_size = b - a + 1;
-		}
-		/* if no digit is after '-', it's wrong*/
-		if (at_start && in_range)
-			return -EINVAL;
-		if (!(a <= b) || group_size == 0 || !(used_size <= group_size))
-			return -EINVAL;
-		if (b >= nmaskbits)
-			return -ERANGE;
-		while (a <= b) {
-			off = min(b - a + 1, used_size);
-			bitmap_set(maskp, a, off);
-			a += group_size;
-		}
-	} while (buflen && c == ',');
 	return 0;
 }
-
-int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits)
-{
-	char *nl  = strchrnul(bp, '\n');
-	int len = nl - bp;
-
-	return __bitmap_parselist(bp, len, 0, maskp, nmaskbits);
-}
 EXPORT_SYMBOL(bitmap_parselist);
 
 
-- 
2.17.1

Re: [PATCH 2/5] lib: rework bitmap_parselist

[Andy Shevchenko]

On Fri, Apr 05, 2019 at 08:32:08PM +0300, Yury Norov wrote:
> Remove __bitmap_parselist helper and split the function to logical
> parts.

> +static const char *bitmap_getnum(const char *str, unsigned int *num)
> +{
> +	unsigned int n = 0, _num = 0;
> +
> +	if (!isdigit(*str))
> +		return ERR_PTR(-EINVAL);
> +
> +	for (; isdigit(*str); str++) {
> +		_num = _num * 10 + (*str - '0');
> +		if (_num < n)
> +			return ERR_PTR(-EOVERFLOW);
> +
> +		n = _num;
> +	}
> +
> +	*num = _num;
> +
> +	return str;
> +}

This looks like (semi) open coded simple_strtoull()

unsigned long long _num;
char *endp;

_num = simple_strtoull(str, &endp, 10);
if (endp == str)
	return ERR_PTR(-EINVAL);
if (_num > UINT_MAX || (endp - str) > 10)
	return ERR_PTR(-EOVERFLOW);
*num = _num;
return endp;

> +static inline bool end_of_str(char c)
> +{
> +	return c == '\0' || c == '\n';
> +}

This reminds me a check at the end of _kstrtoull(). Can we use same approach in
both cases?

-- 
With Best Regards,
Andy Shevchenko

[PATCH 3/5] lib/test_bitmap: switch test_bitmap_parselist to ktime_get()

[Yury Norov]

test_bitmap_parselist currently uses get_cycles which is not
implemented on some platforms, so use ktime_get() instead.

Signed-off-by: Yury Norov <ynorov@marvell.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 lib/test_bitmap.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 6cd7d0740005..b06e0fd3811b 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -266,15 +266,15 @@ static void __init test_bitmap_parselist(void)
 {
 	int i;
 	int err;
-	cycles_t cycles;
+	ktime_t time;
 	DECLARE_BITMAP(bmap, 2048);
 
 	for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) {
 #define ptest parselist_tests[i]
 
-		cycles = get_cycles();
+		time = ktime_get();
 		err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
-		cycles = get_cycles() - cycles;
+		time = ktime_get() - time;
 
 		if (err != ptest.errno) {
 			pr_err("test %d: input is %s, errno is %d, expected %d\n",
@@ -291,8 +291,7 @@ static void __init test_bitmap_parselist(void)
 
 		if (ptest.flags & PARSE_TIME)
 			pr_err("test %d: input is '%s' OK, Time: %llu\n",
-					i, ptest.in,
-					(unsigned long long)cycles);
+					i, ptest.in, time);
 	}
 }
 
-- 
2.17.1

[PATCH 4/5] lib/test_bitmap: add testcases for bitmap_parselist

[Yury Norov]

Add tests for non-number character, empty regions, integer overflow.

Signed-off-by: Yury Norov <ynorov@marvell.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 lib/test_bitmap.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index b06e0fd3811b..709424a788ee 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -224,7 +224,8 @@ static const unsigned long exp[] __initconst = {
 	BITMAP_FROM_U64(0xffffffff),
 	BITMAP_FROM_U64(0xfffffffe),
 	BITMAP_FROM_U64(0x3333333311111111ULL),
-	BITMAP_FROM_U64(0xffffffff77777777ULL)
+	BITMAP_FROM_U64(0xffffffff77777777ULL),
+	BITMAP_FROM_U64(0),
 };
 
 static const unsigned long exp2[] __initconst = {
@@ -247,19 +248,34 @@ static const struct test_bitmap_parselist parselist_tests[] __initconst = {
 	{0, "1-31:4/4",			&exp[9 * step], 32, 0},
 	{0, "0-31:1/4,32-63:2/4",	&exp[10 * step], 64, 0},
 	{0, "0-31:3/4,32-63:4/4",	&exp[11 * step], 64, 0},
+	{0, "  ,,  0-31:3/4  ,, 32-63:4/4  ,,  ",	&exp[11 * step], 64, 0},
 
 	{0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4",	exp2, 128, 0},
 
 	{0, "0-2047:128/256", NULL, 2048, PARSE_TIME},
 
+	{0, "",				&exp[12], 8, 0},
+	{0, "\n",			&exp[12], 8, 0},
+	{0, ",,  ,,  , ,  ,",		&exp[12], 8, 0},
+	{0, " ,  ,,  , ,   ",		&exp[12], 8, 0},
+	{0, " ,  ,,  , ,   \n",		&exp[12], 8, 0},
+
 	{-EINVAL, "-1",	NULL, 8, 0},
 	{-EINVAL, "-0",	NULL, 8, 0},
 	{-EINVAL, "10-1", NULL, 8, 0},
 	{-EINVAL, "0-31:", NULL, 8, 0},
 	{-EINVAL, "0-31:0", NULL, 8, 0},
+	{-EINVAL, "0-31:0/", NULL, 8, 0},
 	{-EINVAL, "0-31:0/0", NULL, 8, 0},
 	{-EINVAL, "0-31:1/0", NULL, 8, 0},
 	{-EINVAL, "0-31:10/1", NULL, 8, 0},
+	{-EOVERFLOW, "0-98765432123456789:10/1", NULL, 8, 0},
+
+	{-EINVAL, "a-31", NULL, 8, 0},
+	{-EINVAL, "0-a1", NULL, 8, 0},
+	{-EINVAL, "a-31:10/1", NULL, 8, 0},
+	{-EINVAL, "0-31:a/1", NULL, 8, 0},
+	{-EINVAL, "0-\n", NULL, 8, 0},
 };
 
 static void __init test_bitmap_parselist(void)
-- 
2.17.1

Re: [PATCH 4/5] lib/test_bitmap: add testcases for bitmap_parselist

[Guenter Roeck]

On Fri, Apr 05, 2019 at 08:32:10PM +0300, Yury Norov wrote:
> Add tests for non-number character, empty regions, integer overflow.
> 
> Signed-off-by: Yury Norov <ynorov@marvell.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  lib/test_bitmap.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
> index b06e0fd3811b..709424a788ee 100644
> --- a/lib/test_bitmap.c
> +++ b/lib/test_bitmap.c
> @@ -224,7 +224,8 @@ static const unsigned long exp[] __initconst = {
>  	BITMAP_FROM_U64(0xffffffff),
>  	BITMAP_FROM_U64(0xfffffffe),
>  	BITMAP_FROM_U64(0x3333333311111111ULL),
> -	BITMAP_FROM_U64(0xffffffff77777777ULL)
> +	BITMAP_FROM_U64(0xffffffff77777777ULL),
> +	BITMAP_FROM_U64(0),
>  };
>  
>  static const unsigned long exp2[] __initconst = {
> @@ -247,19 +248,34 @@ static const struct test_bitmap_parselist parselist_tests[] __initconst = {
>  	{0, "1-31:4/4",			&exp[9 * step], 32, 0},
>  	{0, "0-31:1/4,32-63:2/4",	&exp[10 * step], 64, 0},
>  	{0, "0-31:3/4,32-63:4/4",	&exp[11 * step], 64, 0},
> +	{0, "  ,,  0-31:3/4  ,, 32-63:4/4  ,,  ",	&exp[11 * step], 64, 0},
>  
>  	{0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4",	exp2, 128, 0},
>  
>  	{0, "0-2047:128/256", NULL, 2048, PARSE_TIME},
>  
> +	{0, "",				&exp[12], 8, 0},
> +	{0, "\n",			&exp[12], 8, 0},
> +	{0, ",,  ,,  , ,  ,",		&exp[12], 8, 0},
> +	{0, " ,  ,,  , ,   ",		&exp[12], 8, 0},
> +	{0, " ,  ,,  , ,   \n",		&exp[12], 8, 0},
> +

This results in error messages such as

test_bitmap: parselist: 17: input is ,, ,,  , ,  ,, result is 0x0, expected 0x11111111
test_bitmap: parselist: 18: input is  ,  ,,  , ,   , result is 0x0, expected 0x11111111

on 32-bit systems. The above should be "&exp[12 * step]".

Guenter

>  	{-EINVAL, "-1",	NULL, 8, 0},
>  	{-EINVAL, "-0",	NULL, 8, 0},
>  	{-EINVAL, "10-1", NULL, 8, 0},
>  	{-EINVAL, "0-31:", NULL, 8, 0},
>  	{-EINVAL, "0-31:0", NULL, 8, 0},
> +	{-EINVAL, "0-31:0/", NULL, 8, 0},
>  	{-EINVAL, "0-31:0/0", NULL, 8, 0},
>  	{-EINVAL, "0-31:1/0", NULL, 8, 0},
>  	{-EINVAL, "0-31:10/1", NULL, 8, 0},
> +	{-EOVERFLOW, "0-98765432123456789:10/1", NULL, 8, 0},
> +
> +	{-EINVAL, "a-31", NULL, 8, 0},
> +	{-EINVAL, "0-a1", NULL, 8, 0},
> +	{-EINVAL, "a-31:10/1", NULL, 8, 0},
> +	{-EINVAL, "0-31:a/1", NULL, 8, 0},
> +	{-EINVAL, "0-\n", NULL, 8, 0},
>  };
>  
>  static void __init test_bitmap_parselist(void)

Re: [PATCH 4/5] lib/test_bitmap: add testcases for bitmap_parselist

[Andy Shevchenko]

On Thu, Apr 11, 2019 at 11:39:46AM -0700, Guenter Roeck wrote:
> On Fri, Apr 05, 2019 at 08:32:10PM +0300, Yury Norov wrote:
> > Add tests for non-number character, empty regions, integer overflow.

> >  	{0, "1-31:4/4",			&exp[9 * step], 32, 0},
> >  	{0, "0-31:1/4,32-63:2/4",	&exp[10 * step], 64, 0},
> >  	{0, "0-31:3/4,32-63:4/4",	&exp[11 * step], 64, 0},
> > +	{0, "  ,,  0-31:3/4  ,, 32-63:4/4  ,,  ",	&exp[11 * step], 64, 0},
> >  
> >  	{0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4",	exp2, 128, 0},
> >  
> >  	{0, "0-2047:128/256", NULL, 2048, PARSE_TIME},
> >  
> > +	{0, "",				&exp[12], 8, 0},
> > +	{0, "\n",			&exp[12], 8, 0},
> > +	{0, ",,  ,,  , ,  ,",		&exp[12], 8, 0},
> > +	{0, " ,  ,,  , ,   ",		&exp[12], 8, 0},
> > +	{0, " ,  ,,  , ,   \n",		&exp[12], 8, 0},
> > +
> 
> This results in error messages such as
> 
> test_bitmap: parselist: 17: input is ,, ,,  , ,  ,, result is 0x0, expected 0x11111111
> test_bitmap: parselist: 18: input is  ,  ,,  , ,   , result is 0x0, expected 0x11111111
> 
> on 32-bit systems. The above should be "&exp[12 * step]".

Nice catch!

-- 
With Best Regards,
Andy Shevchenko

[PATCH 5/5] lib/test_bitmap: add tests for bitmap_parselist_user

[Yury Norov]

Propagate existing bitmap_parselist() tests to bitmap_parselist_user().

Signed-off-by: Yury Norov <ynorov@marvell.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 lib/test_bitmap.c | 46 ++++++++++++++++++++++++++++++++++++----------
 1 file changed, 36 insertions(+), 10 deletions(-)

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 709424a788ee..d4ecac0da160 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -11,6 +11,7 @@
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/uaccess.h>
 
 static unsigned total_tests __initdata;
 static unsigned failed_tests __initdata;
@@ -278,39 +279,63 @@ static const struct test_bitmap_parselist parselist_tests[] __initconst = {
 	{-EINVAL, "0-\n", NULL, 8, 0},
 };
 
-static void __init test_bitmap_parselist(void)
+static void __init __test_bitmap_parselist(int is_user)
 {
 	int i;
 	int err;
 	ktime_t time;
 	DECLARE_BITMAP(bmap, 2048);
+	char *mode = is_user ? "_user"  : "";
 
 	for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) {
 #define ptest parselist_tests[i]
 
-		time = ktime_get();
-		err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
-		time = ktime_get() - time;
+		if (is_user) {
+			mm_segment_t orig_fs = get_fs();
+			size_t len = strlen(ptest.in);
+
+			set_fs(KERNEL_DS);
+			time = ktime_get();
+			err = bitmap_parselist_user(ptest.in, len,
+						    bmap, ptest.nbits);
+			time = ktime_get() - time;
+			set_fs(orig_fs);
+		} else {
+			time = ktime_get();
+			err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
+			time = ktime_get() - time;
+		}
 
 		if (err != ptest.errno) {
-			pr_err("test %d: input is %s, errno is %d, expected %d\n",
-					i, ptest.in, err, ptest.errno);
+			pr_err("parselist%s: %d: input is %s, errno is %d, expected %d\n",
+					mode, i, ptest.in, err, ptest.errno);
 			continue;
 		}
 
 		if (!err && ptest.expected
 			 && !__bitmap_equal(bmap, ptest.expected, ptest.nbits)) {
-			pr_err("test %d: input is %s, result is 0x%lx, expected 0x%lx\n",
-					i, ptest.in, bmap[0], *ptest.expected);
+			pr_err("parselist%s: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
+					mode, i, ptest.in, bmap[0],
+					*ptest.expected);
 			continue;
 		}
 
 		if (ptest.flags & PARSE_TIME)
-			pr_err("test %d: input is '%s' OK, Time: %llu\n",
-					i, ptest.in, time);
+			pr_err("parselist%s: %d: input is '%s' OK, Time: %llu\n",
+					mode, i, ptest.in, time);
 	}
 }
 
+static void __init test_bitmap_parselist(void)
+{
+	__test_bitmap_parselist(0);
+}
+
+static void __init test_bitmap_parselist_user(void)
+{
+	__test_bitmap_parselist(1);
+}
+
 #define EXP_BYTES	(sizeof(exp) * 8)
 
 static void __init test_bitmap_arr32(void)
@@ -383,6 +408,7 @@ static int __init test_bitmap_init(void)
 	test_copy();
 	test_bitmap_arr32();
 	test_bitmap_parselist();
+	test_bitmap_parselist_user();
 	test_mem_optimisations();
 
 	if (failed_tests == 0)
-- 
2.17.1

[PATCH v5 0/5] lib: rework bitmap_parselist and tests

[Yury Norov]

bitmap_parselist has been evolved from a pretty simple idea for long and
now lacks for refactoring. It is not structured, has nested loops and a
set of opaque-named variables.

Things are more complicated because bitmap_parselist() is a part of user
interface, and its behavior should not change.

In this patchset
 - bitmap_parselist_user() made a wrapper on bitmap_parselist();
 - bitmap_parselist() reworked (patch 2);
 - time measurement in test_bitmap_parselist switched to ktime_get
   (patch 3);
 - new tests introduced (patch 4), and
 - bitmap_parselist_user() testing enabled with the same testset as
   bitmap_parselist() (patch 5).


v1: https://lkml.org/lkml/2018/12/23/50
v2: https://www.spinics.net/lists/kernel/msg3048976.html
v3: https://lkml.org/lkml/2019/4/3/68
v4: https://lkml.org/lkml/2019/4/5/640
v5: - fix sadly missed '* step' in patch 4, as spotted by Guenter Roeck;
    - use _parse_integer() in bitmap_getnum() to avoid opencoding
      mentioned by Andy Shevchenko.

Yury Norov (5):
  lib: make bitmap_parselist_user() a wrapper on bitmap_parselist()
  lib: rework bitmap_parselist
  lib/test_bitmap: switch test_bitmap_parselist to ktime_get()
  lib/test_bitmap: add testcases for bitmap_parselist
  lib/test_bitmap: add tests for bitmap_parselist_user

 lib/bitmap.c      | 274 ++++++++++++++++++++++++++--------------------
 lib/test_bitmap.c |  67 +++++++++---
 2 files changed, 207 insertions(+), 134 deletions(-)

-- 
2.17.1

[PATCH 5/5] lib/test_bitmap: add tests for bitmap_parselist_user

[Yury Norov]

From: Yury Norov <ynorov@marvell.com>

Propagate existing bitmap_parselist() tests to bitmap_parselist_user().

Signed-off-by: Yury Norov <ynorov@marvell.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 lib/test_bitmap.c | 46 ++++++++++++++++++++++++++++++++++++----------
 1 file changed, 36 insertions(+), 10 deletions(-)

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 6640a82ad44b..d3a501f2a81a 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -11,6 +11,7 @@
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/uaccess.h>
 
 #include "../tools/testing/selftests/kselftest_module.h"
 
@@ -280,39 +281,63 @@ static const struct test_bitmap_parselist parselist_tests[] __initconst = {
 	{-EINVAL, "0-\n", NULL, 8, 0},
 };
 
-static void __init test_bitmap_parselist(void)
+static void __init __test_bitmap_parselist(int is_user)
 {
 	int i;
 	int err;
 	ktime_t time;
 	DECLARE_BITMAP(bmap, 2048);
+	char *mode = is_user ? "_user"  : "";
 
 	for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) {
 #define ptest parselist_tests[i]
 
-		time = ktime_get();
-		err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
-		time = ktime_get() - time;
+		if (is_user) {
+			mm_segment_t orig_fs = get_fs();
+			size_t len = strlen(ptest.in);
+
+			set_fs(KERNEL_DS);
+			time = ktime_get();
+			err = bitmap_parselist_user(ptest.in, len,
+						    bmap, ptest.nbits);
+			time = ktime_get() - time;
+			set_fs(orig_fs);
+		} else {
+			time = ktime_get();
+			err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
+			time = ktime_get() - time;
+		}
 
 		if (err != ptest.errno) {
-			pr_err("test %d: input is %s, errno is %d, expected %d\n",
-					i, ptest.in, err, ptest.errno);
+			pr_err("parselist%s: %d: input is %s, errno is %d, expected %d\n",
+					mode, i, ptest.in, err, ptest.errno);
 			continue;
 		}
 
 		if (!err && ptest.expected
 			 && !__bitmap_equal(bmap, ptest.expected, ptest.nbits)) {
-			pr_err("test %d: input is %s, result is 0x%lx, expected 0x%lx\n",
-					i, ptest.in, bmap[0], *ptest.expected);
+			pr_err("parselist%s: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
+					mode, i, ptest.in, bmap[0],
+					*ptest.expected);
 			continue;
 		}
 
 		if (ptest.flags & PARSE_TIME)
-			pr_err("test %d: input is '%s' OK, Time: %llu\n",
-					i, ptest.in, time);
+			pr_err("parselist%s: %d: input is '%s' OK, Time: %llu\n",
+					mode, i, ptest.in, time);
 	}
 }
 
+static void __init test_bitmap_parselist(void)
+{
+	__test_bitmap_parselist(0);
+}
+
+static void __init test_bitmap_parselist_user(void)
+{
+	__test_bitmap_parselist(1);
+}
+
 #define EXP_BYTES	(sizeof(exp) * 8)
 
 static void __init test_bitmap_arr32(void)
@@ -385,6 +410,7 @@ static void __init selftest(void)
 	test_copy();
 	test_bitmap_arr32();
 	test_bitmap_parselist();
+	test_bitmap_parselist_user();
 	test_mem_optimisations();
 }
 
-- 
2.17.1