There is no guarantee that *src does not contain garbage bits outside
the lower nbits, so we need to mask it before the shift-and-assign.

Signed-off-by: Rasmus Villemoes <li...@rasmusvillemoes.dk>
---
 include/linux/bitmap.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 2100378..75df61d 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -284,7 +284,7 @@ static inline void bitmap_shift_right(unsigned long *dst,
                        const unsigned long *src, int n, int nbits)
 {
        if (small_const_nbits(nbits))
-               *dst = *src >> n;
+               *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> n;
        else
                __bitmap_shift_right(dst, src, n, nbits);
 }
-- 
1.9.2

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