[PATCH 3.2 092/152] regulator: core: fix race condition in regulator_put()
3.2.67-rc1 review patch. If anyone has any objections, please let me know. -- From: Ashay Jaiswal commit 83b0302d347a49f951e904184afe57ac3723476e upstream. The regulator framework maintains a list of consumer regulators for a regulator device and protects it from concurrent access using the regulator device's mutex lock. In the case of regulator_put() the consumer is removed and regulator device's parameters are updated without holding the regulator device's mutex. This would lead to a race condition between the regulator_put() and any function which traverses the consumer list or modifies regulator device's parameters. Fix this race condition by holding the regulator device's mutex in case of regulator_put. Signed-off-by: Ashay Jaiswal Signed-off-by: Mark Brown [bwh: Backported to 3.2: - Adjust context - Don't touch the comment; __regulator_put() has not been split out of regulator_put() here] Signed-off-by: Ben Hutchings --- drivers/regulator/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1314,12 +1314,14 @@ void regulator_put(struct regulator *reg device_remove_file(regulator->dev, >dev_attr); kfree(regulator->dev_attr.attr.name); } + mutex_lock(>mutex); kfree(regulator->supply_name); list_del(>list); kfree(regulator); rdev->open_count--; rdev->exclusive = 0; + mutex_unlock(>mutex); module_put(rdev->owner); mutex_unlock(_list_mutex); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 3.2 092/152] regulator: core: fix race condition in regulator_put()
3.2.67-rc1 review patch. If anyone has any objections, please let me know. -- From: Ashay Jaiswal ash...@codeaurora.org commit 83b0302d347a49f951e904184afe57ac3723476e upstream. The regulator framework maintains a list of consumer regulators for a regulator device and protects it from concurrent access using the regulator device's mutex lock. In the case of regulator_put() the consumer is removed and regulator device's parameters are updated without holding the regulator device's mutex. This would lead to a race condition between the regulator_put() and any function which traverses the consumer list or modifies regulator device's parameters. Fix this race condition by holding the regulator device's mutex in case of regulator_put. Signed-off-by: Ashay Jaiswal ash...@codeaurora.org Signed-off-by: Mark Brown broo...@kernel.org [bwh: Backported to 3.2: - Adjust context - Don't touch the comment; __regulator_put() has not been split out of regulator_put() here] Signed-off-by: Ben Hutchings b...@decadent.org.uk --- drivers/regulator/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1314,12 +1314,14 @@ void regulator_put(struct regulator *reg device_remove_file(regulator-dev, regulator-dev_attr); kfree(regulator-dev_attr.attr.name); } + mutex_lock(rdev-mutex); kfree(regulator-supply_name); list_del(regulator-list); kfree(regulator); rdev-open_count--; rdev-exclusive = 0; + mutex_unlock(rdev-mutex); module_put(rdev-owner); mutex_unlock(regulator_list_mutex); -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
