Revert "virtio-console: remove unnecessary kmemdup()"

This reverts commit 9db81eca10ba2d84177fa076704db3a5d76863c3.

A dependant patch on this one needs to be reverted, so this one also
needs to be reverted at this point in time.

Link: https://lore.kernel.org/r/208f7a41-a9fa-630c-cb44-c37c503f3a72@kernel.org
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Cc: Xianting Tian <xianting.tian@linux.alibaba.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 4ed3ffb..7eaf303 100644 (file)
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1117,6 +1117,8 @@ static int put_chars(u32 vtermno, const char *buf, int count)
 {
        struct port *port;
        struct scatterlist sg[1];
+       void *data;
+       int ret;
 
        if (unlikely(early_put_chars))
                return early_put_chars(vtermno, buf, count);
@@ -1125,8 +1127,14 @@ static int put_chars(u32 vtermno, const char *buf, int count)
        if (!port)
                return -EPIPE;
 
-       sg_init_one(sg, buf, count);
-       return __send_to_port(port, sg, 1, count, (void *)buf, false);
+       data = kmemdup(buf, count, GFP_ATOMIC);
+       if (!data)
+               return -ENOMEM;
+
+       sg_init_one(sg, data, count);
+       ret = __send_to_port(port, sg, 1, count, data, false);
+       kfree(data);
+       return ret;
 }
 
 /*