diff options
| author | Greg Hackmann <ghackmann@google.com> | 2016-11-18 11:09:02 -0800 |
|---|---|---|
| committer | Greg Hackmann <ghackmann@google.com> | 2016-11-18 19:28:54 +0000 |
| commit | 37e461fc4453488c394ccdbdcb8e286c122b047a (patch) | |
| tree | 031b2e7ca7146c79825625c48d90866680459679 | |
| parent | 5f93f3cb3ab26abd6791bc1f01e6a9db73e65536 (diff) | |
ANDROID: goldfish: goldfish_pipe: fix locking errors
If the get_user_pages_fast() call in goldfish_pipe_read_write() failed,
it would return while still holding pipe->lock.
goldfish_pipe_read_write() later releases and tries to re-acquire
pipe->lock. If the re-acquire call failed, goldfish_pipe_read_write()
would try unlock pipe->lock on exit anyway.
This fixes the smatch messages:
drivers/platform/goldfish/goldfish_pipe.c:392 goldfish_pipe_read_write() error: double unlock 'mutex:&pipe->lock'
drivers/platform/goldfish/goldfish_pipe.c:397 goldfish_pipe_read_write() warn: inconsistent returns 'mutex:&pipe->lock'.
Change-Id: Ifd06a76b32027ca451a001704ade0c5440ed69c4
Signed-off-by: Greg Hackmann <ghackmann@google.com>
| -rw-r--r-- | drivers/platform/goldfish/goldfish_pipe.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c index cf7ce97e7346..fd1452e28352 100644 --- a/drivers/platform/goldfish/goldfish_pipe.c +++ b/drivers/platform/goldfish/goldfish_pipe.c @@ -273,11 +273,13 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer, if (ret == 0) { DPRINT("%s: error: (requested pages == 0) (wanted %d)\n", __FUNCTION__, requested_pages); + mutex_unlock(&pipe->lock); return ret; } if (ret < 0) { DPRINT("%s: (requested pages < 0) %d \n", __FUNCTION__, requested_pages); + mutex_unlock(&pipe->lock); return ret; } @@ -384,10 +386,8 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer, } /* Try to re-acquire the lock */ - if (mutex_lock_interruptible(&pipe->lock)) { - ret = -ERESTARTSYS; - break; - } + if (mutex_lock_interruptible(&pipe->lock)) + return -ERESTARTSYS; } mutex_unlock(&pipe->lock); |