From: Wen Yang wenyang@linux.alibaba.com
[ Upstream commit a3cde9534ebdafe18a9bbab208df724c57e6c8e8 ]
There are several issues with the error handling code of the regulator_register() function: ret = device_register(&rdev->dev); if (ret != 0) { put_device(&rdev->dev); --> rdev released goto unset_supplies; } ... unset_supplies: ... unset_regulator_supplies(rdev); --> use-after-free ... clean: if (dangling_of_gpiod) gpiod_put(config->ena_gpiod); kfree(rdev); --> double free
We add a variable to record the failure of device_register() and move put_device() down a bit to avoid the above issues.
Fixes: c438b9d01736 ("regulator: core: Move registration of regulator device") Signed-off-by: Wen Yang wenyang@linux.alibaba.com Cc: Liam Girdwood lgirdwood@gmail.com Cc: Mark Brown broonie@kernel.org Cc: linux-kernel@vger.kernel.org Link: https://lore.kernel.org/r/20191201030250.38074-1-wenyang@linux.alibaba.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/regulator/core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index d66404920976..1dba0bdf3762 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -4992,6 +4992,7 @@ regulator_register(const struct regulator_desc *regulator_desc, struct regulator_dev *rdev; bool dangling_cfg_gpiod = false; bool dangling_of_gpiod = false; + bool reg_device_fail = false; struct device *dev; int ret, i;
@@ -5177,7 +5178,7 @@ regulator_register(const struct regulator_desc *regulator_desc, dev_set_drvdata(&rdev->dev, rdev); ret = device_register(&rdev->dev); if (ret != 0) { - put_device(&rdev->dev); + reg_device_fail = true; goto unset_supplies; }
@@ -5208,7 +5209,10 @@ regulator_register(const struct regulator_desc *regulator_desc, clean: if (dangling_of_gpiod) gpiod_put(config->ena_gpiod); - kfree(rdev); + if (reg_device_fail) + put_device(&rdev->dev); + else + kfree(rdev); kfree(config); rinse: if (dangling_cfg_gpiod)