[PATCH 4.4 13/43] regulator: core: Clear the supply pointer if enabling fails

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jon Hunter <jonathanh@xxxxxxxxxx>

commit 8e5356a73604f53da6a1e0756727cb8f9f7bba17 upstream.

During the resolution of a regulator's supply, we may attempt to enable
the supply if the regulator itself is already enabled. If enabling the
supply fails, then we will call _regulator_put() for the supply.
However, the pointer to the supply has not been cleared for the
regulator and this will cause a crash if we then unregister the
regulator and attempt to call regulator_put() a second time for the
supply. Fix this by clearing the supply pointer if enabling the supply
after fails when resolving the supply for a regulator.

Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Cc: Julia Lawall <julia.lawall@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/regulator/core.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1519,6 +1519,7 @@ static int regulator_resolve_supply(stru
 		ret = regulator_enable(rdev->supply);
 		if (ret < 0) {
 			_regulator_put(rdev->supply);
+			rdev->supply = NULL;
 			return ret;
 		}
 	}