Fix handling of failed read in RNG wrapper.

git-svn-id: https://cryptsetup.googlecode.com/svn/trunk@370 36d66b0a-2a48-0410-832c-cd162a569da5

diff --git a/lib/random.c b/lib/random.c
index 4a64418..b2aafa5 100644 (file)
--- a/lib/random.c
+++ b/lib/random.c
@@ -53,8 +53,10 @@ static int _get_urandom(struct crypt_device *ctx, char *buf, size_t len)
                r = read(urandom_fd, buf, len);
                if (r == -1 && errno != EINTR)
                        return -EINVAL;
-               len -= r;
-               buf += r;
+               if (r > 0) {
+                       len -= r;
+                       buf += r;
+               }
        }
 
        assert(len == 0);
@@ -111,15 +113,17 @@ static int _get_random(struct crypt_device *ctx, char *buf, size_t len)
 
                        r = read(random_fd, buf, n);
 
-                       if (r == -1 && errno == EINTR)
+                       if (r == -1 && errno == EINTR) {
+                               r = 0;
                                continue;
+                       }
 
                        /* bogus read? */
                        if(r > (int)n)
                                return -EINVAL;
 
                        /* random device is opened with O_NONBLOCK, EAGAIN is expected */
-                       if (r == -1 && (errno != EAGAIN || errno != EWOULDBLOCK))
+                       if (r == -1 && (errno != EAGAIN && errno != EWOULDBLOCK))
                                return -EINVAL;
 
                        if (r > 0) {