From: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue, 16 Feb 2016 13:25:00 +0000 (+0100)
Subject: drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command
X-Git-Tag: v4.4.14-KARO~1162
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b78bd121b4978a8378c8300e0fb2e12c88a05a85;p=karo-tx-linux.git

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/qxl/qxl_ioctl.c b/drivers/gpu/drm/qxl/qxl_ioctl.c
index 2ae8577497ca..7c2e78201ead 100644
--- 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;