releases/4.14.69/mailbox-xgene-slimpro-fix-potential-null-pointer-dereference.patch

   1 From 3512a18cbd8d09e22a790540cb9624c3c49827ba Mon Sep 17 00:00:00 2001
   2 From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
   3 Date: Thu, 26 Jul 2018 12:11:39 -0500
   4 Subject: mailbox: xgene-slimpro: Fix potential NULL pointer dereference
   5
   6 From: Gustavo A. R. Silva <gustavo@embeddedor.com>
   7
   8 commit 3512a18cbd8d09e22a790540cb9624c3c49827ba upstream.
   9
  10 There is a potential execution path in which function
  11 platform_get_resource() returns NULL. If this happens,
  12 we will end up having a NULL pointer dereference.
  13
  14 Fix this by replacing devm_ioremap with devm_ioremap_resource,
  15 which has the NULL check and the memory region request.
  16
  17 This code was detected with the help of Coccinelle.
  18
  19 Cc: stable@vger.kernel.org
  20 Fixes: f700e84f417b ("mailbox: Add support for APM X-Gene platform mailbox driver")
  21 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
  22 Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
  23 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  24
  25 ---
  26  drivers/mailbox/mailbox-xgene-slimpro.c |    6 +++---
  27  1 file changed, 3 insertions(+), 3 deletions(-)
  28
  29 --- a/drivers/mailbox/mailbox-xgene-slimpro.c
  30 +++ b/drivers/mailbox/mailbox-xgene-slimpro.c
  31 @@ -195,9 +195,9 @@ static int slimpro_mbox_probe(struct pla
  32         platform_set_drvdata(pdev, ctx);
  33
  34         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  35 -       mb_base = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
  36 -       if (!mb_base)
  37 -               return -ENOMEM;
  38 +       mb_base = devm_ioremap_resource(&pdev->dev, regs);
  39 +       if (IS_ERR(mb_base))
  40 +               return PTR_ERR(mb_base);
  41
  42         /* Setup mailbox links */
  43         for (i = 0; i < MBOX_CNT; i++) {