diff --git a/src/dump.c b/src/dump.c
index 7c3657f..1931c99 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -203,7 +203,7 @@ int check_badblocks(char *mtddev)
 		} else {
 			char readbuf[2048]; // XXX hardcoded like mtd-utils?? ugly!
 			// dummy -- should be removed
-			if (pread(fd, readbuf, meminfo.writesize, i) != meminfo.writesize) {
+			if (pread(fd, readbuf, meminfo.writesize, i) != (ssize_t)meminfo.writesize) {
 				perror("pread");
 				goto closeall;
 			}
diff --git a/src/fiasco.c b/src/fiasco.c
index d878cd0..b2538f7 100644
--- a/src/fiasco.c
+++ b/src/fiasco.c
@@ -38,7 +38,7 @@
 #define FIASCO_WRITE_ERROR(file, fd, ...) do { ERROR_INFO_STR(file, __VA_ARGS__); if ( fd >= 0 ) close(fd); return -1; } while (0)
 #define READ_OR_FAIL(fiasco, buf, size) do { if ( read(fiasco->fd, buf, size) != size ) { FIASCO_READ_ERROR(fiasco, "Cannot read %d bytes", size); } } while (0)
 #define READ_OR_RETURN(fiasco, buf, size) do { if ( read(fiasco->fd, buf, size) != size ) return fiasco; } while (0)
-#define WRITE_OR_FAIL(file, fd, buf, size) do { if ( ! simulate ) { if ( write(fd, buf, size) != size ) { FIASCO_WRITE_ERROR(file, fd, "Cannot write %d bytes", size); } } } while (0)
+#define WRITE_OR_FAIL(file, fd, buf, size) do { if ( ! simulate ) { if ( write(fd, buf, size) != (ssize_t)size ) { FIASCO_WRITE_ERROR(file, fd, "Cannot write %d bytes", size); } } } while (0)
 
 struct fiasco * fiasco_alloc_empty(void) {
 
diff --git a/src/image.c b/src/image.c
index cfccb49..f8e9c93 100644
--- a/src/image.c
+++ b/src/image.c
@@ -320,7 +320,7 @@ void image_free(struct image * image) {
 
 }
 
-void image_seek(struct image * image, off_t whence) {
+void image_seek(struct image * image, size_t whence) {
 
 	if ( whence > image->size )
 		return;
@@ -339,7 +339,7 @@ void image_seek(struct image * image, off_t whence) {
 
 size_t image_read(struct image * image, void * buf, size_t count) {
 
-	off_t cur;
+	size_t cur;
 	ssize_t ret;
 	size_t new_count = 0;
 	size_t ret_count = 0;
diff --git a/src/image.h b/src/image.h
index 648a090..709fef7 100644
--- a/src/image.h
+++ b/src/image.h
@@ -51,9 +51,9 @@ struct image {
 	int fd;
 	int is_shared_fd;
 	uint32_t align;
-	off_t offset;
-	off_t cur;
-	off_t acur;
+	size_t offset;
+	size_t cur;
+	size_t acur;
 	char * orig_filename;
 };
 
@@ -66,7 +66,7 @@ struct image_list {
 struct image * image_alloc_from_file(const char * file, const char * type, const char * device, const char * hwrevs, const char * version, const char * layout);
 struct image * image_alloc_from_shared_fd(int fd, size_t size, size_t offset, uint16_t hash, const char * type, const char * device, const char * hwrevs, const char * version, const char * layout);
 void image_free(struct image * image);
-void image_seek(struct image * image, off_t whence);
+void image_seek(struct image * image, size_t whence);
 size_t image_read(struct image * image, void * buf, size_t count);
 void image_print_info(struct image * image);
 void image_list_add(struct image_list ** list, struct image * image);