X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Ffs%2Fsysfs%2Ffile.c;fp=kernel%2Ffs%2Fsysfs%2Ffile.c;h=b803213d1307e9137c3bfe5e04ee4ac5bd396cce;hb=52f993b8e89487ec9ee15a7fb4979e0f09a45b27;hp=f35523d4fa3a6d657260e7b04d5273db2dcd53b1;hpb=c189ccac5702322ed843fe17057035b7222a59b6;p=kvmfornfv.git

diff --git a/kernel/fs/sysfs/file.c b/kernel/fs/sysfs/file.c
index f35523d4f..b803213d1 100644
--- a/kernel/fs/sysfs/file.c
+++ b/kernel/fs/sysfs/file.c
@@ -114,9 +114,15 @@ static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf,
 	 * If buf != of->prealloc_buf, we don't know how
 	 * large it is, so cannot safely pass it to ->show
 	 */
-	if (pos || WARN_ON_ONCE(buf != of->prealloc_buf))
+	if (WARN_ON_ONCE(buf != of->prealloc_buf))
 		return 0;
 	len = ops->show(kobj, of->kn->priv, buf);
+	if (pos) {
+		if (len <= pos)
+			return 0;
+		len -= pos;
+		memmove(buf, buf + pos, len);
+	}
 	return min(count, len);
 }