releases/4.19.31/mfd-sm501-fix-potential-null-pointer-dereference.patch

   1 From ae7b8eda27b33b1f688dfdebe4d46f690a8f9162 Mon Sep 17 00:00:00 2001
   2 From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
   3 Date: Tue, 22 Jan 2019 10:56:36 -0600
   4 Subject: mfd: sm501: Fix potential NULL pointer dereference
   5
   6 From: Gustavo A. R. Silva <gustavo@embeddedor.com>
   7
   8 commit ae7b8eda27b33b1f688dfdebe4d46f690a8f9162 upstream.
   9
  10 There is a potential NULL pointer dereference in case devm_kzalloc()
  11 fails and returns NULL.
  12
  13 Fix this by adding a NULL check on *lookup*
  14
  15 This bug was detected with the help of Coccinelle.
  16
  17 Fixes: b2e63555592f ("i2c: gpio: Convert to use descriptors")
  18 Cc: stable@vger.kernel.org
  19 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
  20 Signed-off-by: Lee Jones <lee.jones@linaro.org>
  21 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  22
  23 ---
  24  drivers/mfd/sm501.c |    3 +++
  25  1 file changed, 3 insertions(+)
  26
  27 --- a/drivers/mfd/sm501.c
  28 +++ b/drivers/mfd/sm501.c
  29 @@ -1145,6 +1145,9 @@ static int sm501_register_gpio_i2c_insta
  30         lookup = devm_kzalloc(&pdev->dev,
  31                               sizeof(*lookup) + 3 * sizeof(struct gpiod_lookup),
  32                               GFP_KERNEL);
  33 +       if (!lookup)
  34 +               return -ENOMEM;
  35 +
  36         lookup->dev_id = "i2c-gpio";
  37         if (iic->pin_sda < 32)
  38                 lookup->table[0].chip_label = "SM501-LOW";