diff options
author | Ashay Jaiswal <ashayj@codeaurora.org> | 2015-01-08 18:54:25 +0530 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2015-02-20 00:49:35 +0000 |
commit | 3a8a47c5a3d71507abed60d05af1826f334d1e3e (patch) | |
tree | a75d4d771359ed5c1e26c59b0593ac33c286db6a /drivers | |
parent | 1c5b4c2b70b1c388e34874b2a3acda64f46bbc9a (diff) |
regulator: core: fix race condition in regulator_put()
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 <ashayj@codeaurora.org>
Signed-off-by: Mark Brown <broonie@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 <ben@decadent.org.uk>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/regulator/core.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 6ec610c3b724..adba3d6495c0 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1314,12 +1314,14 @@ void regulator_put(struct regulator *regulator) device_remove_file(regulator->dev, ®ulator->dev_attr); kfree(regulator->dev_attr.attr.name); } + mutex_lock(&rdev->mutex); kfree(regulator->supply_name); list_del(®ulator->list); kfree(regulator); rdev->open_count--; rdev->exclusive = 0; + mutex_unlock(&rdev->mutex); module_put(rdev->owner); mutex_unlock(®ulator_list_mutex); |