diff options
| author |   Shengjiu Wang <shengjiu.wang@nxp.com> | 2022-05-21 11:35:05 +0800 |
|---|---|---|
| committer |   Mathieu Poirier <mathieu.poirier@linaro.org> | 2022-06-14 14:58:10 -0600 |
| commit | abe13e9a561d6b3e82b21362c0d6dd3ecd8a5b13 (patch) | |
| tree | 8f964772405ec041206ea18b0f55434b03b19625 /drivers/rpmsg | |
| parent | Linux 5.19-rc2 (diff) | |
| download | wireguard-linux-abe13e9a561d6b3e82b21362c0d6dd3ecd8a5b13.tar.xz wireguard-linux-abe13e9a561d6b3e82b21362c0d6dd3ecd8a5b13.zip | |
rpmsg: char: Add mutex protection for rpmsg_eptdev_open()
There is no mutex protection for rpmsg_eptdev_open(),
especially for eptdev->ept read and write operation.
It may cause issues when multiple instances call
rpmsg_eptdev_open() in parallel,the return state
may be success or EBUSY.
Fixes: 964e8bedd5a1 ("rpmsg: char: Return an error if device already open")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1653104105-16779-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Diffstat (limited to 'drivers/rpmsg')
| -rw-r--r-- | drivers/rpmsg/rpmsg_char.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c index b6183d4f62a2..4f2189111494 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -120,8 +120,11 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) struct rpmsg_device *rpdev = eptdev->rpdev; struct device *dev = &eptdev->dev; - if (eptdev->ept) + mutex_lock(&eptdev->ept_lock); + if (eptdev->ept) { + mutex_unlock(&eptdev->ept_lock); return -EBUSY; + } get_device(dev); @@ -137,11 +140,13 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) if (!ept) { dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); put_device(dev); + mutex_unlock(&eptdev->ept_lock); return -EINVAL; } eptdev->ept = ept; filp->private_data = eptdev; + mutex_unlock(&eptdev->ept_lock); return 0; } |