Bug#1091694: Memory leak in libsasl2-modules DIGEST-MD5 module

[Greg Hudson]

Package: libsasl2-modules
Version: 2.1.28+dfsg-10

The Debian patch 0029-Load-OpenSSL3-legacy-provider-digestmd5.patch 
introduces a memory leak into plugins/digestmd5.c:init_rc4().  It adds a 
call to:

    cipher = EVP_CIPHER_fetch(ossl3_ctx->libctx, "RC4", "");

but does not free the result with EVP_CIPHER_free().  I successfully 
tested a fix, which was to initialize cipher to NULL and add just after 
done: block:

#if OPENSSL_VERSION_NUMBER >= 0x30000000L
    EVP_CIPHER_free(cipher);
#endif