thodg/cgminer

diff --git a/cgminer.c b/cgminer.c
index 042661d..f6ac12d 100644
--- a/cgminer.c
+++ b/cgminer.c
@@ -239,7 +239,7 @@ int swork_id;
 struct stratum_share {
 	UT_hash_handle hh;
 	bool block;
-	struct work work;
+	struct work *work;
 	int id;
 };
 
@@ -1469,9 +1469,7 @@ static void calc_diff(struct work *work, int known);
 static void gen_gbt_work(struct pool *pool, struct work *work)
 {
 	unsigned char *merkleroot;
-	char *cbhex;
 
-	memset(work->job_id, 0, 64);
 	mutex_lock(&pool->gbt_lock);
 	__build_gbt_coinbase(pool);
 	merkleroot = __gbt_merkleroot(pool);
@@ -1483,15 +1481,13 @@ static void gen_gbt_work(struct pool *pool, struct work *work)
 
 	memcpy(work->target, pool->gbt_target, 32);
 
-	cbhex = bin2hex(pool->gbt_coinbase, pool->coinbase_len);
-	sprintf(work->gbt_coinbase, "%s", cbhex);
-	free(cbhex);
+	work->gbt_coinbase = bin2hex(pool->gbt_coinbase, pool->coinbase_len);
 
 	/* For encoding the block data on submission */
 	work->gbt_txns = pool->gbt_txns + 1;
 
 	if (pool->gbt_workid)
-		sprintf(work->job_id, "%s", pool->gbt_workid);
+		work->job_id = strdup(pool->gbt_workid);
 	mutex_unlock(&pool->gbt_lock);
 
 	memcpy(work->data + 4 + 32, merkleroot, 32);
@@ -2307,7 +2303,7 @@ static bool submit_upstream_work(struct work *work, CURL *curl, bool resubmit)
 
 	/* build JSON-RPC request */
 	if (work->gbt) {
-		char gbt_block[1024], *varint, *header;
+		char gbt_block[4096], *varint, *header;
 		unsigned char data[80];
 
 		flip80(data, work->data);
@@ -2334,7 +2330,7 @@ static bool submit_upstream_work(struct work *work, CURL *curl, bool resubmit)
 		free(varint);
 		strcat(gbt_block, work->gbt_coinbase);
 
-		if (strlen(work->job_id))
+		if (work->job_id)
 			sprintf(s, "{\"id\": 0, \"method\": \"submitblock\", \"params\": [\"%s\", {\"workid\": \"%s\"}]}", gbt_block, work->job_id);
 		else
 			sprintf(s, "{\"id\": 0, \"method\": \"submitblock\", \"params\": [\"%s\", {}]}", gbt_block);
@@ -2634,8 +2630,25 @@ static struct work *make_work(void)
 	return work;
 }
 
-static void free_work(struct work *work)
+/* This is the central place all work that is about to be retired should be
+ * cleaned to remove any dynamically allocated arrays within the struct */
+void clean_work(struct work *work)
+{
+	free(work->job_id);
+	free(work->nonce2);
+	free(work->ntime);
+	free(work->gbt_coinbase);
+	work->job_id = NULL;
+	work->nonce2 = NULL;
+	work->ntime = NULL;
+	work->gbt_coinbase = NULL;
+}
+
+/* All dynamically allocated work structs should be freed here to not leak any
+ * ram from arrays allocated within the work struct */
+void free_work(struct work *work)
 {
+	clean_work(work);
 	free(work);
 }
 
@@ -2948,11 +2961,37 @@ static void roll_work(struct work *work)
 	work->id = total_work++;
 }
 
+/* Duplicates any dynamically allocated arrays within the work struct to
+ * prevent a copied work struct from freeing ram belonging to another struct */
+void __copy_work(struct work *work, struct work *base_work)
+{
+	clean_work(work);
+	memcpy(work, base_work, sizeof(struct work));
+	if (work->job_id)
+		work->job_id = strdup(base_work->job_id);
+	if (work->nonce2)
+		work->nonce2 = strdup(base_work->nonce2);
+	if (work->ntime)
+		work->ntime = strdup(base_work->ntime);
+	if (work->gbt_coinbase)
+		work->gbt_coinbase = strdup(base_work->gbt_coinbase);
+}
+
+/* Generates a copy of an existing work struct, creating fresh heap allocations
+ * for all dynamically allocated arrays within the struct */
+struct work *copy_work(struct work *base_work)
+{
+	struct work *work = make_work();
+
+ 	__copy_work(work, base_work);
+
+	return work;
+}
+
 static struct work *make_clone(struct work *work)
 {
-	struct work *work_clone = make_work();
+	struct work *work_clone = copy_work(work);
 
-	memcpy(work_clone, work, sizeof(struct work));
 	work_clone->clone = true;
 	gettimeofday((struct timeval *)&(work_clone->tv_cloned), NULL);
 	work_clone->longpoll = false;
@@ -3016,7 +3055,7 @@ static void gen_stratum_work(struct pool *pool, struct work *work);
 static void *get_work_thread(void *userdata)
 {
 	struct workio_cmd *wc = (struct workio_cmd *)userdata;
-	struct work *ret_work= NULL;
+	struct work *ret_work = NULL;
 	struct curl_ent *ce = NULL;
 	struct pool *pool;
 
@@ -3232,7 +3271,7 @@ static void *submit_work_thread(void *userdata)
 		char *noncehex;
 		char s[1024];
 
-		memcpy(&sshare->work, work, sizeof(struct work));
+		sshare->work = copy_work(work);
 		mutex_lock(&sshare_lock);
 		/* Give the stratum share a unique id */
 		sshare->id = swork_id++;
@@ -4538,7 +4577,7 @@ out_unlock:
 static void stratum_share_result(json_t *val, json_t *res_val, json_t *err_val,
 				 struct stratum_share *sshare)
 {
-	struct work *work = &sshare->work;
+	struct work *work = sshare->work;
 	uint64_t sharediff = share_diff(work);
 	char hashshow[65];
 	uint32_t *hash32;
@@ -4602,6 +4641,7 @@ static bool parse_stratum_response(struct pool *pool, char *s)
 		goto out;
 	}
 	stratum_share_result(val, res_val, err_val, sshare);
+	free_work(sshare->work);
 	free(sshare);
 
 	ret = true;
@@ -4621,8 +4661,9 @@ static void clear_stratum_shares(struct pool *pool)
 
 	mutex_lock(&sshare_lock);
 	HASH_ITER(hh, stratum_shares, sshare, tmpshare) {
-		if (sshare->work.pool == pool) {
+		if (sshare->work->pool == pool) {
 			HASH_DEL(stratum_shares, sshare);
+			free_work(sshare->work);
 			free(sshare);
 			cleared++;
 		}
@@ -5129,17 +5170,13 @@ static void gen_stratum_work(struct pool *pool, struct work *work)
 {
 	unsigned char *coinbase, merkle_root[32], merkle_sha[64], *merkle_hash;
 	int len, cb1_len, n1_len, cb2_len, i;
-	char header[260], *nonce2;
 	uint32_t *data32, *swap32;
-
-	memset(work->job_id, 0, 64);
-	memset(work->nonce2, 0, 64);
-	memset(work->ntime, 0, 16);
+	char header[260];
 
 	mutex_lock(&pool->pool_lock);
 
 	/* Generate coinbase */
-	nonce2 = bin2hex((const unsigned char *)&pool->nonce2, pool->n2size);
+	work->nonce2 = bin2hex((const unsigned char *)&pool->nonce2, pool->n2size);
 	pool->nonce2++;
 	cb1_len = strlen(pool->swork.coinbase1) / 2;
 	n1_len = strlen(pool->nonce1) / 2;
@@ -5148,7 +5185,7 @@ static void gen_stratum_work(struct pool *pool, struct work *work)
 	coinbase = alloca(len + 1);
 	hex2bin(coinbase, pool->swork.coinbase1, cb1_len);
 	hex2bin(coinbase + cb1_len, pool->nonce1, n1_len);
-	hex2bin(coinbase + cb1_len + n1_len, nonce2, pool->n2size);
+	hex2bin(coinbase + cb1_len + n1_len, work->nonce2, pool->n2size);
 	hex2bin(coinbase + cb1_len + n1_len + pool->n2size, pool->swork.coinbase2, cb2_len);
 
 	/* Generate merkle root */
@@ -5181,10 +5218,8 @@ static void gen_stratum_work(struct pool *pool, struct work *work)
 	work->sdiff = pool->swork.diff;
 
 	/* Copy parameters required for share submission */
-	sprintf(work->job_id, "%s", pool->swork.job_id);
-	sprintf(work->nonce2, "%s", nonce2);
-	sprintf(work->ntime, "%s", pool->swork.ntime);
-	free(nonce2);
+	work->job_id = strdup(pool->swork.job_id);
+	work->ntime = strdup(pool->swork.ntime);
 
 	mutex_unlock(&pool->pool_lock);
 
@@ -5225,6 +5260,8 @@ static void get_work(struct work *work, struct thr_info *thr, const int thr_id)
 	 * should not be restarted */
 	thread_reportout(thr);
 
+	clean_work(work);
+
 	if (opt_benchmark) {
 		get_benchmark_work(work);
 		goto out;
@@ -5298,7 +5335,7 @@ retry:
 			pool_resus(pool);
 	}
 
-	memcpy(work, work_heap, sizeof(struct work));
+	__copy_work(work, work_heap);
 	free_work(work_heap);
 
 out:
@@ -5307,7 +5344,7 @@ out:
 	work->mined = true;
 }
 
-bool submit_work_sync(struct thr_info *thr, const struct work *work_in, struct timeval *tv_work_found)
+bool submit_work_sync(struct thr_info *thr, struct work *work_in, struct timeval *tv_work_found)
 {
 	struct workio_cmd *wc;
 
@@ -5318,10 +5355,9 @@ bool submit_work_sync(struct thr_info *thr, const struct work *work_in, struct t
 		return false;
 	}
 
-	wc->work = make_work();
+	wc->work = copy_work(work_in);
 	wc->cmd = WC_SUBMIT_WORK;
 	wc->thr = thr;
-	memcpy(wc->work, work_in, sizeof(*work_in));
 	if (tv_work_found)
 		memcpy(&(wc->work->tv_work_found), tv_work_found, sizeof(struct timeval));
 
diff --git a/driver-modminer.c b/driver-modminer.c
index d169cfd..3fbedb4 100644
--- a/driver-modminer.c
+++ b/driver-modminer.c
@@ -645,7 +645,7 @@ static int64_t modminer_scanhash(struct thr_info *thr, struct work *work, int64_
 	if (startwork) {
 		if (!modminer_start_work(thr))
 			return -1;
-		memcpy(&state->running_work, work, sizeof(state->running_work));
+		__copy_work(&state->running_work, work);
 	}
 
 	// This is intentionally early
diff --git a/driver-opencl.c b/driver-opencl.c
index 3ce14a5..8c801e1 100644
--- a/driver-opencl.c
+++ b/driver-opencl.c
@@ -1464,10 +1464,8 @@ static void opencl_free_work(struct thr_info *thr, struct work *work)
 
 	clFinish(clState->commandQueue);
 
-	if (thrdata->res[FOUND]) {
-		thrdata->last_work = &thrdata->_last_work;
-		memcpy(thrdata->last_work, work, sizeof(*thrdata->last_work));
-	}
+	if (thrdata->res[FOUND])
+		thrdata->last_work = copy_work(&thrdata->_last_work);
 }
 
 static bool opencl_prepare_work(struct thr_info __maybe_unused *thr, struct work *work)
@@ -1535,6 +1533,7 @@ static int64_t opencl_scanhash(struct thr_info *thr, struct work *work,
 		if (unlikely(thrdata->last_work)) {
 			applog(LOG_DEBUG, "GPU %d found something in last work?", gpu->device_id);
 			postcalc_hash_async(thr, thrdata->last_work, thrdata->res);
+			free_work(thrdata->last_work);
 			thrdata->last_work = NULL;
 		} else {
 			applog(LOG_DEBUG, "GPU %d found something?", gpu->device_id);
diff --git a/miner.h b/miner.h
index f098e23..0a97e4a 100644
--- a/miner.h
+++ b/miner.h
@@ -962,15 +962,13 @@ struct work {
 	bool		queued;
 
 	bool		stratum;
-	/* These are arbitrary lengths as it is too hard to keep track of
-	 * dynamically allocated ram in work structs */
-	char 		job_id[64];
-	char		nonce2[64];
-	char		ntime[16];
+	char 		*job_id;
+	char		*nonce2;
+	char		*ntime;
 	double		sdiff;
 
 	bool		gbt;
-	char		gbt_coinbase[512];
+	char		*gbt_coinbase;
 	int		gbt_txns;
 
 	unsigned int	work_block;
@@ -1031,6 +1029,10 @@ extern void tq_thaw(struct thread_q *tq);
 extern bool successful_connect;
 extern void adl(void);
 extern void app_restart(void);
+extern void clean_work(struct work *work);
+extern void free_work(struct work *work);
+extern void __copy_work(struct work *work, struct work *base_work);
+extern struct work *copy_work(struct work *base_work);
 
 enum api_data_type {
 	API_ESCAPE,