[PATCH] regulator: core: fix possible NULL dereference

[PATCH] regulator: core: fix possible NULL dereference

[Sudip Mukherjee]

We were checking rdev->supply for NULL after dereferencing it. Lets
check for rdev->supply along with _regulator_is_enabled() and call
regulator_enable() only if rdev->supply is not NULL.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
---
 drivers/regulator/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 7a85ac9..9283d9f 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1422,11 +1422,10 @@ static int regulator_resolve_supply(struct regulator_dev *rdev)
 		return ret;
 
 	/* Cascade always-on state to supply */
-	if (_regulator_is_enabled(rdev)) {
+	if (_regulator_is_enabled(rdev) && rdev->supply) {
 		ret = regulator_enable(rdev->supply);
 		if (ret < 0) {
-			if (rdev->supply)
-				_regulator_put(rdev->supply);
+			_regulator_put(rdev->supply);
 			return ret;
 		}
 	}
-- 
1.9.1

Applied "regulator: core: fix possible NULL dereference" to the regulator tree

[Mark Brown]

The patch

   regulator: core: fix possible NULL dereference

has been applied to the regulator tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 9f8df6adf6c53abfa10e243cb289c34eb18ec581 Mon Sep 17 00:00:00 2001
From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Date: Wed, 2 Sep 2015 16:14:06 +0530
Subject: [PATCH] regulator: core: fix possible NULL dereference

We were checking rdev->supply for NULL after dereferencing it. Lets
check for rdev->supply along with _regulator_is_enabled() and call
regulator_enable() only if rdev->supply is not NULL.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/regulator/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index de9f272a0faf..7150ff6ef46b 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1422,11 +1422,10 @@ static int regulator_resolve_supply(struct regulator_dev *rdev)
 		return ret;
 
 	/* Cascade always-on state to supply */
-	if (_regulator_is_enabled(rdev)) {
+	if (_regulator_is_enabled(rdev) && rdev->supply) {
 		ret = regulator_enable(rdev->supply);
 		if (ret < 0) {
-			if (rdev->supply)
-				_regulator_put(rdev->supply);
+			_regulator_put(rdev->supply);
 			return ret;
 		}
 	}
-- 
2.5.0