fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / lib / bitmap.c

diff --git a/lib/bitmap.c b/lib/bitmap.c
index d71e38c..037fa9a 100644 (file)
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -316,10 +316,11 @@ int bitmap_scnprintf(char *buf, unsigned int buflen,
 EXPORT_SYMBOL(bitmap_scnprintf);
 
 /**
- * bitmap_parse - convert an ASCII hex string into a bitmap.
- * @ubuf: pointer to buffer in user space containing string.
- * @ubuflen: buffer size in bytes.  If string is smaller than this
+ * __bitmap_parse - convert an ASCII hex string into a bitmap.
+ * @buf: pointer to buffer containing string.
+ * @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
  * @maskp: pointer to bitmap array that will contain result.
  * @nmaskbits: size of bitmap, in bits.
  *
@@ -330,11 +331,13 @@ EXPORT_SYMBOL(bitmap_scnprintf);
  * characters and for grouping errors such as "1,,5", ",44", "," and "".
  * Leading and trailing whitespace accepted, but not embedded whitespace.
  */
-int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
-        unsigned long *maskp, int nmaskbits)
+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;
        u32 chunk;
+       const char __user *ubuf = buf;
 
        bitmap_zero(maskp, nmaskbits);
 
@@ -343,11 +346,15 @@ int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
                chunk = ndigits = 0;
 
                /* Get the next chunk of the bitmap */
-               while (ubuflen) {
+               while (buflen) {
                        old_c = c;
-                       if (get_user(c, ubuf++))
-                               return -EFAULT;
-                       ubuflen--;
+                       if (is_user) {
+                               if (__get_user(c, ubuf++))
+                                       return -EFAULT;
+                       }
+                       else
+                               c = *buf++;
+                       buflen--;
                        if (isspace(c))
                                continue;
 
@@ -388,11 +395,36 @@ int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
                nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ;
                if (nbits > nmaskbits)
                        return -EOVERFLOW;
-       } while (ubuflen && c == ',');
+       } while (buflen && c == ',');
 
        return 0;
 }
-EXPORT_SYMBOL(bitmap_parse);
+EXPORT_SYMBOL(__bitmap_parse);
+
+/**
+ * bitmap_parse_user()
+ *
+ * @ubuf: pointer to user buffer containing string.
+ * @ulen: buffer size in bytes.  If string is smaller than this
+ *    then it must be terminated with a \0.
+ * @maskp: pointer to bitmap array that will contain result.
+ * @nmaskbits: size of bitmap, in bits.
+ *
+ * Wrapper for __bitmap_parse(), 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_parse_user(const char __user *ubuf,
+                       unsigned int ulen, unsigned long *maskp,
+                       int nmaskbits)
+{
+       if (!access_ok(VERIFY_READ, ubuf, ulen))
+               return -EFAULT;
+       return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits);
+}
+EXPORT_SYMBOL(bitmap_parse_user);
 
 /*
  * bscnl_emit(buf, buflen, rbot, rtop, bp)