Sometimes the input from user may cause an unexpected result.

just like __bitmap_parse, we return -EINVAL if there is no avaiable digit in 
each
parsing procedures.

Signed-off-by: Pan Xinhui <xinhuix....@intel.com>
---
 lib/bitmap.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 64c0926..995fca2 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -504,7 +504,7 @@ static int __bitmap_parselist(const char *buf, unsigned int 
buflen,
                int nmaskbits)
 {
        unsigned a, b;
-       int c, old_c, totaldigits;
+       int c, old_c, totaldigits, ndigits;
        const char __user __force *ubuf = (const char __user __force *)buf;
        int exp_digit, in_range;
@@ -514,6 +514,7 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
                exp_digit = 1;
                in_range = 0;
                a = b = 0;
+               ndigits = 0;
/* Get the next cpu# or a range of cpu#'s */
                while (buflen) {
@@ -555,8 +556,10 @@ static int __bitmap_parselist(const char *buf, unsigned 
int buflen,
                        if (!in_range)
                                a = b;
                        exp_digit = 0;
-                       totaldigits++;
+                       ndigits++; totaldigits++;
                }
+               if (ndigits == 0)
+                       return -EINVAL;
                if (!(a <= b))
                        return -EINVAL;
                if (b >= nmaskbits)
--
1.9.1
--
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