add __bitmap_parse_common to match any contents and return expected reslut.

as __bitmap_parse_common need NULL-terminated string, we alloc a new buf.

this patch also fix an unexpected parse result issue in __bitmap_parselist.

Signed-off-by: Pan Xinhui <xinhuix....@intel.com>
---
 lib/bitmap.c | 238 +++++++++++++++++++++++++++++++++--------------------------
 1 file changed, 134 insertions(+), 104 deletions(-)
---
change log
v3:
__bitmap_parselist now allow some extra input, like ",2, 3,,,,  5-8", at least 
one digit inside.
input like " " ", " is still not allowed.

V2:
__bitmap_parse_common need *base* to parse correct result

V1:
add __bitmap_parse_common and rewrite __bitmap_parse && __bitmap_parselist
---

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 64c0926..f2095e1d 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -16,6 +16,8 @@
 #include <asm/page.h>
 #include <asm/uaccess.h>
+#include <linux/parser.h>
+#include <linux/slab.h>
 /*
  * bitmaps provide an array of bits, implemented using an an
  * array of unsigned longs.  The number of valid bits in a
@@ -331,6 +333,58 @@ again:
 EXPORT_SYMBOL(bitmap_find_next_zero_area_off);
/*
+ * __bitmap_parse_common - parse expected number from buf
+ * Return 0 on success.
+ * there two patterns.
+ * if buf's contents did not match any of them, reutrn equivalent error.
+ * Notice buf's contents may be changed.
+ */
+static int __bitmap_parse_common(char *buf, unsigned int buflen,
+                unsigned long *a, unsigned long *b, int base)
+{
+       int ret;
+       int token;
+       const match_table_t table = {
+               {
+                       .token = 1,
+                       .pattern = "%x",
+               },
+               {
+                       .token = 2,
+                       .pattern = "%x-%x",
+               },
+               {
+                       .token = 0,
+                       .pattern = NULL,
+               }
+       };
+       substring_t substr[MAX_OPT_ARGS];
+
+       if (!buflen || !a)
+               return -EINVAL;
+
+       token = match_token((char *)buf, table, substr);
+       switch (token) {
+       case 1:
+               *substr[0].to = '\0';
+               ret = kstrtoul(substr[0].from, base, a);
+               if (b)
+                       *b = *a;
+               break;
+       case 2:
+               *substr[0].to = '\0';
+               *substr[1].to = '\0';
+               ret = kstrtoul(substr[0].from, base, a);
+               ret |= b ? kstrtoul(substr[1].from, base, b) : -EINVAL;
+               break;
+       default:
+               ret = -EINVAL;
+               break;
+       }
+       return ret;
+}
+
+/*
  * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers,
  * second version by Paul Jackson, third by Joe Korty.
  */
@@ -359,57 +413,45 @@ int __bitmap_parse(const char *buf, unsigned int buflen,
                int is_user, unsigned long *maskp,
                int nmaskbits)
 {
-       int c, old_c, totaldigits, ndigits, nchunks, nbits;
+       int nchunks, nbits, ret;
+       unsigned long a;
        u32 chunk;
        const char __user __force *ubuf = (const char __user __force *)buf;
+       char *kbuf, *endp;
+
+       if (!buflen)
+               return -EINVAL;
+       kbuf = kmalloc(buflen + 1, GFP_KERNEL);
+       if (!kbuf)
+               return -ENOMEM;
+       if (is_user) {
+               if (copy_from_user(kbuf, ubuf, buflen) != 0) {
+                       kfree(kbuf);
+                       return -EFAULT;
+               }
+       } else
+               memcpy(kbuf, buf, buflen);
+       kbuf[buflen] = '\0';
+       buf = strim(kbuf);
bitmap_zero(maskp, nmaskbits); - nchunks = nbits = totaldigits = c = 0;
+       nchunks = nbits = 0;
        do {
-               chunk = ndigits = 0;
-
-               /* Get the next chunk of the bitmap */
-               while (buflen) {
-                       old_c = c;
-                       if (is_user) {
-                               if (__get_user(c, ubuf++))
-                                       return -EFAULT;
-                       }
-                       else
-                               c = *buf++;
-                       buflen--;
-                       if (isspace(c))
-                               continue;
-
-                       /*
-                        * If the last character was a space and the current
-                        * character isn't '\0', we've got embedded whitespace.
-                        * This is a no-no, so throw an error.
-                        */
-                       if (totaldigits && c && isspace(old_c))
-                               return -EINVAL;
-
-                       /* A '\0' or a ',' signal the end of the chunk */
-                       if (c == '\0' || c == ',')
-                               break;
-
-                       if (!isxdigit(c))
-                               return -EINVAL;
-
-                       /*
-                        * Make sure there are at least 4 free bits in 'chunk'.
-                        * If not, this hexdigit will overflow 'chunk', so
-                        * throw an error.
-                        */
-                       if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1))
-                               return -EOVERFLOW;
-
-                       chunk = (chunk << 4) | hex_to_bin(c);
-                       ndigits++; totaldigits++;
+               endp = strchr(buf, ',');
+               if (endp)
+                       *endp = '\0';
+               ret = __bitmap_parse_common((char *)buf, strlen(buf),
+                                                               &a, NULL, 16);
+               if (ret)
+                       break;
+               buf = endp + 1;
+
+               if (unlikely(a > U32_MAX)) {
+                       ret = -ERANGE;
+                       break;
                }
-               if (ndigits == 0)
-                       return -EINVAL;
+               chunk = (u32)a;
                if (nchunks == 0 && chunk == 0)
                        continue;
@@ -417,11 +459,13 @@ int __bitmap_parse(const char *buf, unsigned int buflen,
                *maskp |= chunk;
                nchunks++;
                nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ;
-               if (nbits > nmaskbits)
-                       return -EOVERFLOW;
-       } while (buflen && c == ',');
-
-       return 0;
+               if (nbits > nmaskbits) {
+                       ret = -EOVERFLOW;
+                       break;
+               }
+       } while (endp);
+       kfree(kbuf);
+       return ret;
 }
 EXPORT_SYMBOL(__bitmap_parse);
@@ -503,70 +547,56 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
                int is_user, unsigned long *maskp,
                int nmaskbits)
 {
-       unsigned a, b;
-       int c, old_c, totaldigits;
+       unsigned long a, b;
+       int ret = -EINVAL;
        const char __user __force *ubuf = (const char __user __force *)buf;
-       int exp_digit, in_range;
+       char *kbuf, *endp, *ibuf;
+
+       if (!buflen)
+               return -EINVAL;
+       ibuf = kbuf = kmalloc(buflen + 1, GFP_KERNEL);
+       if (!kbuf)
+               return -ENOMEM;
+       if (is_user) {
+               if (copy_from_user(kbuf, ubuf, buflen) != 0) {
+                       kfree(kbuf);
+                       return -EFAULT;
+               }
+       } else
+               memcpy(kbuf, buf, buflen);
+       kbuf[buflen] = '\0';
- totaldigits = c = 0;
        bitmap_zero(maskp, nmaskbits);
        do {
-               exp_digit = 1;
-               in_range = 0;
-               a = b = 0;
-
-               /* 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;
-
-                       /*
-                        * If the last character was a space and the current
-                        * character isn't '\0', we've got embedded whitespace.
-                        * This is a no-no, so throw an error.
-                        */
-                       if (totaldigits && c && isspace(old_c))
-                               return -EINVAL;
-
-                       /* A '\0' or a ',' signal the end of a cpu# or range */
-                       if (c == '\0' || c == ',')
-                               break;
-
-                       if (c == '-') {
-                               if (exp_digit || in_range)
-                                       return -EINVAL;
-                               b = 0;
-                               in_range = 1;
-                               exp_digit = 1;
-                               continue;
-                       }
-
-                       if (!isdigit(c))
-                               return -EINVAL;
-
-                       b = b * 10 + (c - '0');
-                       if (!in_range)
-                               a = b;
-                       exp_digit = 0;
-                       totaldigits++;
+               endp = strchr(ibuf, ',');
+               if (endp)
+                       *endp = '\0';
+               ibuf = strim(ibuf);
+               if (*ibuf == 0) {
+                       ibuf = endp + 1;
+                       continue;
+               }
+               ret = __bitmap_parse_common(ibuf, strlen(ibuf),
+                                                               &a, &b, 0);
+               if (ret)
+                       break;
+               ibuf = endp + 1;
+
+               if (!(a <= b)) {
+                       ret = -EINVAL;
+                       break;
+               }
+               if (b >= nmaskbits) {
+                       ret = -ERANGE;
+                       break;
                }
-               if (!(a <= b))
-                       return -EINVAL;
-               if (b >= nmaskbits)
-                       return -ERANGE;
                while (a <= b) {
                        set_bit(a, maskp);
                        a++;
                }
-       } while (buflen && c == ',');
-       return 0;
+       } while (endp);
+       kfree(kbuf);
+       return ret;
 }
int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits)
--
1.9.1
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