diff --git a/client/flash.c b/client/flash.c
index de6fdf7e6..2c06311c3 100644
--- a/client/flash.c
+++ b/client/flash.c
@@ -38,7 +38,7 @@ static int build_segs_from_phdrs(flash_file_t *ctx, FILE *fd, Elf32_Phdr *phdrs,
 	flash_seg_t *seg;
 	uint32_t last_end = 0;
 
-	ctx->segments = malloc(sizeof(flash_seg_t) * num_phdrs);
+	ctx->segments = calloc(sizeof(flash_seg_t) * num_phdrs, sizeof(uint8_t));
 	if (!ctx->segments) {
 		fprintf(stderr, "Out of memory\n");
 		return -1;
@@ -88,7 +88,7 @@ static int build_segs_from_phdrs(flash_file_t *ctx, FILE *fd, Elf32_Phdr *phdrs,
 
 		uint8_t *data;
 		// make extra space if we need to move the data forward
-		data = malloc(filesz + BLOCK_SIZE);
+		data = calloc(filesz + BLOCK_SIZE, sizeof(uint8_t));
 		if (!data) {
 			fprintf(stderr, "Error: Out of memory\n");
 			return -1;
@@ -111,7 +111,7 @@ static int build_segs_from_phdrs(flash_file_t *ctx, FILE *fd, Elf32_Phdr *phdrs,
 					uint32_t new_length = this_end - prev_seg->start;
 					uint32_t this_offset = paddr - prev_seg->start;
 					uint32_t hole = this_offset - prev_seg->length;
-					uint8_t *new_data = malloc(new_length);
+					uint8_t *new_data = calloc(new_length, sizeof(uint8_t));
 					if (!new_data) {
 						fprintf(stderr, "Error: Out of memory\n");
 						free(data);
@@ -223,7 +223,7 @@ int flash_load(flash_file_t *ctx, const char *name, int can_write_bl) {
 	}
 	num_phdrs = le16(ehdr.e_phnum);
 
-	phdrs = malloc(le16(ehdr.e_phnum) * sizeof(Elf32_Phdr));
+	phdrs = calloc(le16(ehdr.e_phnum) * sizeof(Elf32_Phdr), sizeof(uint8_t));
 	if (!phdrs) {
 		fprintf(stderr, "Out of memory\n");
 		goto fail;