Fix integer overflow when computing the progress percentage

cmdline/state.c

@@ -4245,7 +4245,7 @@ void state_progress_end(struct snapraid_state* state, block_off_t countpos, bloc
 
 		elapsed = now - state->progress_whole_start - state->progress_wasted;
 
-		msg_bar("%u%% completed, %u MB accessed", countpos * 100 / countmax, countsize_MB);
+		msg_bar("%u%% completed, %u MB accessed", muldiv(countpos, 100, countmax), countsize_MB);
 
 		msg_bar(" in %u:%02u", (unsigned)(elapsed / 3600), (unsigned)((elapsed % 3600) / 60));
 
@@ -4405,7 +4405,7 @@ static void state_progress_graph(struct snapraid_state* state, struct snapraid_i
 		struct snapraid_disk* disk = i->data;
 		v = disk->progress_tick[current] - ref(disk->progress_tick, oldest);
 		printr(disk->name, pad);
-		printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+		printf("%3u%% | ", muldiv(v, 100, tick_total));
 		printc('*', v * bar / tick_total);
 		printf("\n");
 
@@ -4416,32 +4416,32 @@ static void state_progress_graph(struct snapraid_state* state, struct snapraid_i
 	for (l = 0; l < state->level; ++l) {
 		v = state->parity[l].progress_tick[current] - ref(state->parity[l].progress_tick, oldest);
 		printr(lev_config_name(l), pad);
-		printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+		printf("%3u%% | ", muldiv(v, 100, tick_total));
 		printc('*', v * bar / tick_total);
 		printf("\n");
 	}
 
 	v = state->progress_tick_raid[current] - ref(state->progress_tick_raid, oldest);
 	printr("raid", pad);
-	printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+	printf("%3u%% | ", muldiv(v, 100, tick_total));
 	printc('*', v * bar / tick_total);
 	printf("\n");
 
 	v = state->progress_tick_hash[current] - ref(state->progress_tick_hash, oldest);
 	printr("hash", pad);
-	printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+	printf("%3u%% | ", muldiv(v, 100, tick_total));
 	printc('*', v * bar / tick_total);
 	printf("\n");
 
 	v = state->progress_tick_sched[current] - ref(state->progress_tick_sched, oldest);
 	printr("sched", pad);
-	printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+	printf("%3u%% | ", muldiv(v, 100, tick_total));
 	printc('*', v * bar / tick_total);
 	printf("\n");
 
 	v = state->progress_tick_misc[current] - ref(state->progress_tick_misc, oldest);
 	printr("misc", pad);
-	printf("%3" PRIu64 "%% | ", v * 100 / tick_total);
+	printf("%3u%% | ", muldiv(v, 100, tick_total));
 	printc('*', v * bar / tick_total);
 	printf("\n");
 
@@ -4499,7 +4499,7 @@ int state_progress(struct snapraid_state* state, struct snapraid_io* io, block_o
 
 		/* completion percentage */
 		if (countmax)
-			out_perc = countpos * 100 / countmax;
+			out_perc = muldiv(countpos, 100, countmax);
 
 		/* if we have at least 5 measures */
 		if (state->progress_tick >= 5
@@ -4565,11 +4565,11 @@ int state_progress(struct snapraid_state* state, struct snapraid_io* io, block_o
 
 			/* estimate the cpu usage percentage */
 			if (delta_tick_total != 0)
-				out_cpu = (unsigned)(delta_tick_cpu * 100U / delta_tick_total);
+				out_cpu = muldiv(delta_tick_cpu, 100, delta_tick_total);
 
 			/* estimate the remaining time in minutes */
 			if (delta_pos != 0)
-				out_eta = (countmax - countpos) * delta_time / (60 * delta_pos);
+				out_eta = muldiv(countmax - countpos, delta_time, 60 * delta_pos);
 
 			if (state->opt.force_stats) {
 				os_clear();

cmdline/status.c

@@ -39,14 +39,6 @@ unsigned day_ago(time_t ref, time_t now)
 #define GRAPH_COLUMN 70
 #define GRAPH_ROW 15
 
-static unsigned perc(uint64_t part, uint64_t total)
-{
-	if (!total)
-		return 0;
-
-	return (unsigned)(part * 100 / total);
-}
-
 /**
  * Bit used to mark unscrubbed time info.
  */
@@ -239,7 +231,7 @@ int state_status(struct snapraid_state* state)
 			printf("   - ");
 		} else {
 			printf("%8" PRIu64, (disk_block_max - disk_block_count) * (uint64_t)state->block_size / GIGA);
-			printf(" %3u%%", perc(disk_block_count, disk_block_max));
+			printf(" %3u%%", muldiv(disk_block_count, 100, disk_block_max));
 		}
 		printf(" %s\n", disk->name);
 
@@ -266,7 +258,7 @@ int state_status(struct snapraid_state* state)
 	printf("%8.1f", (double)all_wasted / GIGA);
 	printf("%8" PRIu64, file_size / GIGA);
 	printf("%8" PRIu64, file_block_free * state->block_size / GIGA);
-	printf(" %3u%%", perc(file_block_count, file_block_count + file_block_free));
+	printf(" %3u%%", muldiv(file_block_count, 100, file_block_count + file_block_free));
 	printf("\n");
 
 	/* warn about invalid data free info */
@@ -468,13 +460,13 @@ int state_status(struct snapraid_state* state)
 
 	if (unsynced_blocks) {
 		printf("WARNING! The array is NOT fully synced.\n");
-		printf("You have a sync in progress at %u%%.\n", (blockmax - unsynced_blocks) * 100 / blockmax);
+		printf("You have a sync in progress at %u%%.\n", muldiv(blockmax - unsynced_blocks, 100, blockmax));
 	} else {
 		printf("No sync is in progress.\n");
 	}
 
 	if (unscrubbed_blocks) {
-		printf("The %u%% of the array is not scrubbed.\n", (unscrubbed_blocks * 100 + blockmax - 1) / blockmax);
+		printf("The %u%% of the array is not scrubbed.\n", muldiv_upper(unscrubbed_blocks, 100, blockmax));
 	} else {
 		printf("The full array was scrubbed at least one time.\n");
 	}
@@ -487,7 +479,7 @@ int state_status(struct snapraid_state* state)
 	}
 
 	if (rehash) {
-		printf("You have a rehash in progress at %u%%.\n", (count - rehash) * 100 / count);
+		printf("You have a rehash in progress at %u%%.\n", muldiv(count - rehash, 100, count));
 	} else {
 		if (state->besthash != state->hash) {
 			printf("No rehash is in progress, but for optimal performance one is recommended.\n");

cmdline/util.c

@@ -672,3 +672,22 @@ int lock_unlock(int f)
 }
 #endif
 
+/****************************************************************************/
+/* muldiv */
+
+unsigned muldiv(uint64_t v, uint64_t mul, uint64_t div)
+{
+	if (!div)
+		return 0;
+
+	return (uint32_t)(v * mul / div);
+}
+
+unsigned muldiv_upper(uint64_t v, uint64_t mul, uint64_t div)
+{
+	if (!div)
+		return 0;
+
+	return (uint32_t)((v * mul + div - 1) / div);
+}
+

cmdline/util.h

@@ -251,5 +251,10 @@ static inline int bit_vect_test(bit_vect_t* bit_vect, size_t off)
 	return (bit_vect[off / BIT_VECT_SIZE] & mask) != 0;
 }
 
-#endif
+/****************************************************************************/
+/* muldiv */
 
+unsigned muldiv(uint64_t v, uint64_t mul, uint64_t div);
+unsigned muldiv_upper(uint64_t v, uint64_t mul, uint64_t div);
+
+#endif