drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command

commit 34855706c30d52b0a744da44348b5d1cc39fbe51 upstream.

This avoids integer overflows on 32bit machines when calculating
reloc_info size, as reported by Alan Cox.

Cc: gnomes@lxorguk.ukuu.org.uk
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/gpu/drm/qxl/qxl_ioctl.c b/drivers/gpu/drm/qxl/qxl_ioctl.c
index 729debf83fa3f36dc8f56dc70cd480570b864551..94008582b5e008d02794f57b1648279e8da97232 100644 (file)
--- a/drivers/gpu/drm/qxl/qxl_ioctl.c
+++ b/drivers/gpu/drm/qxl/qxl_ioctl.c
@@ -168,7 +168,8 @@ static int qxl_process_single_command(struct qxl_device *qdev,
                       cmd->command_size))
                return -EFAULT;
 
-       reloc_info = kmalloc(sizeof(struct qxl_reloc_info) * cmd->relocs_num, GFP_KERNEL);
+       reloc_info = kmalloc_array(cmd->relocs_num,
+                                  sizeof(struct qxl_reloc_info), GFP_KERNEL);
        if (!reloc_info)
                return -ENOMEM;