libfdisk: reset errno before calling read()

The else branch will be executed on short reads.
For those errno is not reset so a random left-over errno value may be
checked.

Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>

diff --git a/libfdisk/src/utils.c b/libfdisk/src/utils.c
index 38ad233933af60ee8a3fce6b828cb08cf914110e..6b6167d478681545d5b406d9b4240709508aed4e 100644 (file)
--- a/libfdisk/src/utils.c
+++ b/libfdisk/src/utils.c
@@ -29,6 +29,7 @@ static int read_from_device(struct fdisk_context *cxt,
                return -errno;
        }
 
+       errno = 0;
        r = read(cxt->dev_fd, buf, size);
        if (r < 0 || (size_t)r != size) {
                if (!errno)