Fix memory leak in mbedtls_mpi_sub_abs
Fix a memory leak in mbedtls_mpi_sub_abs when the output parameter is
aliased to the second operand (X = A - X) and the result is negative.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/library/bignum.c b/library/bignum.c
index fa97d19..b11239e 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -1411,7 +1411,10 @@
/* If we ran out of space for the carry, it means that the result
* is negative. */
if( n == X->n )
- return( MBEDTLS_ERR_MPI_NEGATIVE_VALUE );
+ {
+ ret = MBEDTLS_ERR_MPI_NEGATIVE_VALUE;
+ goto cleanup;
+ }
--X->p[n];
}