| Message ID | 1653104105-16779-1-git-send-email-shengjiu.wang@nxp.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [RESEND] rpmsg: char: Add mutex protection for rpmsg_eptdev_open() | expand |
On Sat, May 21, 2022 at 11:35:05AM +0800, Shengjiu Wang wrote: > 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 EBUGY. > > Fixes: 964e8bedd5a1 ("rpmsg: char: Return an error if device already open") > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> This looks good. I will fix the above typo and apply the patch when the 5.19 cycle starts. Thanks, Mathieu > --- > changes in resend: > - add fixes tag > > drivers/rpmsg/rpmsg_char.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > 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; > } > -- > 2.17.1 >
On Sat, May 21, 2022 at 11:35:05AM +0800, Shengjiu Wang wrote: > 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 EBUGY. > > Fixes: 964e8bedd5a1 ("rpmsg: char: Return an error if device already open") > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> > --- > changes in resend: > - add fixes tag > > drivers/rpmsg/rpmsg_char.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) I have applied your patch. Thanks, Mathieu > > 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; > } > -- > 2.17.1 >
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; }
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 EBUGY. Fixes: 964e8bedd5a1 ("rpmsg: char: Return an error if device already open") Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> --- changes in resend: - add fixes tag drivers/rpmsg/rpmsg_char.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)