mei: fix krealloc() misuse in in mei_cl_irq_read_msg()

If krealloc() returns NULL, it doesn't free the original. So any code
of the form 'foo = krealloc(foo, ...);' is almost certainly a bug.

Introduced by commit fcb136e1ac5774909e0d85189f721b8dfa800e0f(mei: fix
reading large reposnes)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 5ee2f07c929d..1473cfdbc426 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -148,16 +148,16 @@ static int mei_cl_irq_read_msg(struct mei_device *dev,
                         dev_dbg(&dev->pdev->dev, "message overflow. size %d len %d idx %ld\n",
                                 cb->response_buffer.size,
                                 mei_hdr->length, cb->buf_idx);
-                        cb->response_buffer.data =
-                                        krealloc(cb->response_buffer.data,
-                                        mei_hdr->length + cb->buf_idx,
-                                        GFP_KERNEL);
+                        buffer = krealloc(cb->response_buffer.data,
+                                          mei_hdr->length + cb->buf_idx,
+                                          GFP_KERNEL);
 
-                        if (!cb->response_buffer.data) {
+                        if (!buffer) {
                                 dev_err(&dev->pdev->dev, "allocation failed.\n");
                                 list_del(&cb->list);
                                 return -ENOMEM;
                         }
+                        cb->response_buffer.data = buffer;
                         cb->response_buffer.size =
                                 mei_hdr->length + cb->buf_idx;
                 }