1 files changed, 21 insertions, 2 deletions
diff --git a/wrapper.c b/wrapper.c
index 52001789de..9afc1a021c 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -152,6 +152,9 @@ void *xcalloc(size_t nmemb, size_t size)
 {
 	void *ret;
 
+	if (unsigned_mult_overflows(nmemb, size))
+		die("data too large to fit into virtual memory space");
+
 	memory_limit_check(size * nmemb, 0);
 	ret = calloc(nmemb, size);
 	if (!ret && (!nmemb || !size))
@@ -236,8 +239,24 @@ ssize_t xread(int fd, void *buf, size_t len)
 	    len = MAX_IO_SIZE;
 	while (1) {
 		nr = read(fd, buf, len);
-		if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
-			continue;
+		if (nr < 0) {
+			if (errno == EINTR)
+				continue;
+			if (errno == EAGAIN || errno == EWOULDBLOCK) {
+				struct pollfd pfd;
+				pfd.events = POLLIN;
+				pfd.fd = fd;
+				/*
+				 * it is OK if this poll() failed; we
+				 * want to leave this infinite loop
+				 * only when read() returns with
+				 * success, or an expected failure,
+				 * which would be checked by the next
+				 * call to read(2).
+				 */
+				poll(&pfd, 1, -1);
+			}
+		}
 		return nr;
 	}
 }