crypto: rsa - Check MPI allocation errors

Fixes: 6637e11e4ad2 ("crypto: rsa - allow only odd e and restrict value in FIPS mode")
Fixes: f145d411a67e ("crypto: rsa - implement Chinese Remainder Theorem for faster private key operation")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/rsa.c b/crypto/rsa.c
index d9be9e8..78b28d1 100644 (file)
--- a/crypto/rsa.c
+++ b/crypto/rsa.c
@@ -98,14 +98,13 @@ static int _rsa_dec_crt(const struct rsa_mpi_key *key, MPI m_or_m1_or_h, MPI c)
                goto err_free_mpi;
 
        /* (2iii) h = (m_1 - m_2) * qInv mod p */
-       mpi_sub(m12_or_qh, m_or_m1_or_h, m2);
-       mpi_mulm(m_or_m1_or_h, m12_or_qh, key->qinv, key->p);
+       ret = mpi_sub(m12_or_qh, m_or_m1_or_h, m2) ?:
+             mpi_mulm(m_or_m1_or_h, m12_or_qh, key->qinv, key->p);
 
        /* (2iv) m = m_2 + q * h */
-       mpi_mul(m12_or_qh, key->q, m_or_m1_or_h);
-       mpi_addm(m_or_m1_or_h, m2, m12_or_qh, key->n);
-
-       ret = 0;
+       ret = ret ?:
+             mpi_mul(m12_or_qh, key->q, m_or_m1_or_h) ?:
+             mpi_addm(m_or_m1_or_h, m2, m12_or_qh, key->n);
 
 err_free_mpi:
        mpi_free(m12_or_qh);
@@ -236,6 +235,7 @@ static int rsa_check_key_length(unsigned int len)
 static int rsa_check_exponent_fips(MPI e)
 {
        MPI e_max = NULL;
+       int err;
 
        /* check if odd */
        if (!mpi_test_bit(e, 0)) {
@@ -250,7 +250,12 @@ static int rsa_check_exponent_fips(MPI e)
        e_max = mpi_alloc(0);
        if (!e_max)
                return -ENOMEM;
-       mpi_set_bit(e_max, 256);
+
+       err = mpi_set_bit(e_max, 256);
+       if (err) {
+               mpi_free(e_max);
+               return err;
+       }
 
        if (mpi_cmp(e, e_max) >= 0) {
                mpi_free(e_max);