Port fix from v3.1.x

diff --git a/src/main/tls.c b/src/main/tls.c
index bc9e233d6a7b66744fbafeed7ff7afaa5b9624d9..2d0ff04d38c69b551b4db40b876059ddcadce15c 100644 (file)
--- a/src/main/tls.c
+++ b/src/main/tls.c
@@ -1303,8 +1303,11 @@ static SSL_SESSION *cbtls_get_session(SSL *ssl, unsigned char *data, int len, in
        {
                int             rv, fd, todo;
                char            filename[256];
-               unsigned char   *p;
-               unsigned char const *q;
+
+               unsigned char const     **o;
+               unsigned char           **p;
+               uint8_t                 *q;
+
                struct stat     st;
                VALUE_PAIR      *vps = NULL;
 
@@ -1340,24 +1343,34 @@ static SSL_SESSION *cbtls_get_session(SSL *ssl, unsigned char *data, int len, in
                        goto err;
                }
 
-               p = sess_data;
+               q = sess_data;
                todo = st.st_size;
                while (todo > 0) {
-                       rv = read(fd, p, todo);
+                       rv = read(fd, q, todo);
                        if (rv < 1) {
                                RWDEBUG("Failed reading persisted session: %s", fr_syserror(errno));
                                close(fd);
                                goto err;
                        }
                        todo -= rv;
-                       p += rv;
+                       q += rv;
                }
                close(fd);
 
-               /* openssl mutates &p */
+               /*
+                *      OpenSSL mutates what's passed in, so we assign sess_data to q,
+                *      so the value of q gets mutated, and not the value of sess_data.
+                *
+                *      We then need a pointer to hold &q, but it can't be const, because
+                *      clang complains about lack of consting in nested pointer types.
+                *
+                *      So we memcpy the value of that pointer, to one that
+                *      does have a const, which we then pass into d2i_SSL_SESSION *sigh*.
+                */
                q = sess_data;
-               sess = d2i_SSL_SESSION(NULL, &q, st.st_size);
-
+               p = &q;
+               memcpy(&o, &p, sizeof(o));
+               sess = d2i_SSL_SESSION(NULL, o, st.st_size);
                if (!sess) {
                        RWDEBUG("Failed loading persisted session: %s", ERR_error_string(ERR_get_error(), NULL));
                        goto err;