* [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open()
@ 2022-05-21 3:35 Shengjiu Wang
2022-05-31 17:28 ` Mathieu Poirier
2022-06-14 22:28 ` Mathieu Poirier
0 siblings, 2 replies; 3+ messages in thread
From: Shengjiu Wang @ 2022-05-21 3:35 UTC (permalink / raw)
To: bjorn.andersson, mathieu.poirier, arnaud.pouliquen
Cc: linux-remoteproc, linux-kernel, shengjiu.wang
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(-)
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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open()
2022-05-21 3:35 [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open() Shengjiu Wang
@ 2022-05-31 17:28 ` Mathieu Poirier
2022-06-14 22:28 ` Mathieu Poirier
1 sibling, 0 replies; 3+ messages in thread
From: Mathieu Poirier @ 2022-05-31 17:28 UTC (permalink / raw)
To: Shengjiu Wang
Cc: bjorn.andersson, arnaud.pouliquen, linux-remoteproc,
linux-kernel, shengjiu.wang
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
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open()
2022-05-21 3:35 [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open() Shengjiu Wang
2022-05-31 17:28 ` Mathieu Poirier
@ 2022-06-14 22:28 ` Mathieu Poirier
1 sibling, 0 replies; 3+ messages in thread
From: Mathieu Poirier @ 2022-06-14 22:28 UTC (permalink / raw)
To: Shengjiu Wang
Cc: bjorn.andersson, arnaud.pouliquen, linux-remoteproc,
linux-kernel, shengjiu.wang
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
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-06-14 22:29 UTC | newest]
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2022-05-21 3:35 [RESEND PATCH] rpmsg: char: Add mutex protection for rpmsg_eptdev_open() Shengjiu Wang
2022-05-31 17:28 ` Mathieu Poirier
2022-06-14 22:28 ` Mathieu Poirier
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