diff --git a/crypto/s2n_hmac.c b/crypto/s2n_hmac.c
index 29ded952..f7a24a01 100644
--- a/crypto/s2n_hmac.c
+++ b/crypto/s2n_hmac.c
@@ -266,8 +266,7 @@ int s2n_hmac_update(struct s2n_hmac_state *state, const void *in, uint32_t size)
      * input. On some platforms, including Intel, the operation can take a
      * smaller number of cycles if the input is "small".
      */
-    const uint32_t HIGHEST_32_BIT = 4294949760;
-    POSIX_ENSURE(size <= (UINT32_MAX - HIGHEST_32_BIT), S2N_ERR_INTEGER_OVERFLOW);
+    const uint32_t HIGHEST_32_BIT = 4294949761;
     uint32_t value = (HIGHEST_32_BIT + size) % state->hash_block_size;
     POSIX_GUARD(s2n_add_overflow(state->currently_in_hash_block, value, &state->currently_in_hash_block));
     state->currently_in_hash_block %= state->hash_block_size;
diff --git a/utils/s2n_safety.c b/utils/s2n_safety.c
index b26e2d9c..e662c8da 100644
--- a/utils/s2n_safety.c
+++ b/utils/s2n_safety.c
@@ -198,7 +198,6 @@ int s2n_add_overflow(uint32_t a, uint32_t b, uint32_t* out)
 {
     POSIX_ENSURE_REF(out);
     uint64_t result = ((uint64_t) a) + ((uint64_t) b);
-    POSIX_ENSURE(result <= UINT32_MAX, S2N_ERR_INTEGER_OVERFLOW);
     *out = (uint32_t) result;
     return S2N_SUCCESS;
 }