Fix possible infinite loop in pem_read_bio_key_decoder()
There could be an infinite loop if no read happened.
Fixes
@@ -36,6 +36,11 @@ static EVP_PKEY *pem_read_bio_key_decoder(BIO *bp, EVP_PKEY **x,
{
EVP_PKEY *pkey = NULL;
OSSL_DECODER_CTX *dctx = NULL;
+ int pos, newpos;
+
+ if ((pos = BIO_tell(bp)) < 0)
+ /* We can depend on BIO_tell() thanks to the BIO_f_readbuffer() */
+ return NULL;
dctx = OSSL_DECODER_CTX_new_for_pkey(&pkey, "PEM", NULL, NULL,
selection, libctx, propq);
@@ -50,8 +55,10 @@ static EVP_PKEY *pem_read_bio_key_decoder(BIO *bp, EVP_PKEY **x,
goto err;
while (!OSSL_DECODER_from_bio(dctx, bp) || pkey == NULL)
- if (BIO_eof(bp) != 0)
+ if (BIO_eof(bp) != 0 || (newpos = BIO_tell(bp)) < 0 || newpos <= pos)
goto err;
+ else
+ pos = newpos;
if (!evp_keymgmt_util_has(pkey, selection)) {
EVP_PKEY_free(pkey);
