Unpoison result of high_bits_free

Previously we unpoisoned the input to high_bit but this is no
longer required. But still the output should be unpoisoned.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/lib/math/bigint/bigint.cpp b/src/lib/math/bigint/bigint.cpp
index 75c87e5b6..065c469b4 100644
--- a/src/lib/math/bigint/bigint.cpp
+++ b/src/lib/math/bigint/bigint.cpp
@@ -280,6 +280,7 @@ size_t BigInt::top_bits_free() const
 
    const word top_word = word_at(words - 1);
    const size_t bits_used = high_bit(top_word);
+   CT::unpoison(bits_used);
    return BOTAN_MP_WORD_BITS - bits_used;
    }