lib/bitmap.c: fix a special string handling bug in __bitmap_parselist

If string end with '-', for exapmle, bitmap_parselist("1,0-",&mask,
nmaskbits), It is not in a valid pattern, so add a check after loop.
Return -EINVAL on such condition.

Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/bitmap.c b/lib/bitmap.c
index eb21456be4b9..f549176e9250 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -546,6 +546,7 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
                                         return -EINVAL;
                                 b = 0;
                                 in_range = 1;
+                                at_start = 1;
                                 continue;
                         }
 
@@ -558,6 +559,9 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
                         at_start = 0;
                         totaldigits++;
                 }
+                /* if no digit is after '-', it's wrong*/
+                if (at_start && in_range)
+                        return -EINVAL;
                 if (!(a <= b))
                         return -EINVAL;
                 if (b >= nmaskbits)