releases/4.9.131/regulator-fix-crash-caused-by-null-driver-data.patch

   1 From fb6de923ca3358a91525552b4907d4cb38730bdd Mon Sep 17 00:00:00 2001
   2 From: Yu Zhao <yuzhao@google.com>
   3 Date: Wed, 19 Sep 2018 15:30:51 -0600
   4 Subject: regulator: fix crash caused by null driver data
   5
   6 From: Yu Zhao <yuzhao@google.com>
   7
   8 commit fb6de923ca3358a91525552b4907d4cb38730bdd upstream.
   9
  10 dev_set_drvdata() needs to be called before device_register()
  11 exposes device to userspace. Otherwise kernel crashes after it
  12 gets null pointer from dev_get_drvdata() when userspace tries
  13 to access sysfs entries.
  14
  15 [Removed backtrace for length -- broonie]
  16
  17 Signed-off-by: Yu Zhao <yuzhao@google.com>
  18 Signed-off-by: Mark Brown <broonie@kernel.org>
  19 Cc: stable@vger.kernel.org
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21
  22 ---
  23  drivers/regulator/core.c |    2 +-
  24  1 file changed, 1 insertion(+), 1 deletion(-)
  25
  26 --- a/drivers/regulator/core.c
  27 +++ b/drivers/regulator/core.c
  28 @@ -4054,13 +4054,13 @@ regulator_register(const struct regulato
  29             !rdev->desc->fixed_uV)
  30                 rdev->is_switch = true;
  31
  32 +       dev_set_drvdata(&rdev->dev, rdev);
  33         ret = device_register(&rdev->dev);
  34         if (ret != 0) {
  35                 put_device(&rdev->dev);
  36                 goto unset_supplies;
  37         }
  38
  39 -       dev_set_drvdata(&rdev->dev, rdev);
  40         rdev_init_debugfs(rdev);
  41
  42         /* try to resolve regulators supply since a new one was registered */