[PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Myungho Jung]

tiocmget() and tiocmset() operations are optional and some tty drivers
like pty miss the operations. We need NULL check to prevent from
dereference.

Signed-off-by: Myungho Jung <mhjungk@gmail.com>
---
 drivers/bluetooth/hci_ath.c   | 6 ++++++
 drivers/bluetooth/hci_ldisc.c | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
index d568fbd94d6c..fb9f6323a911 100644
--- a/drivers/bluetooth/hci_ath.c
+++ b/drivers/bluetooth/hci_ath.c
@@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
 
 static int ath_setup(struct hci_uart *hu)
 {
+	struct tty_struct *tty = hu->tty;
+
 	BT_DBG("hu %p", hu);
 
+	/* tty driver should support operations to set RTS */
+	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
+		return -EOPNOTSUPP;
+
 	hu->hdev->set_bdaddr = ath_set_bdaddr;
 
 	return 0;
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index fbf7b4df23ab..cb31c2d8d826 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -314,6 +314,10 @@ void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
 		return;
 	}
 
+	/* tiocmget() and tiocmset() operations are optional */
+	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
+		return;
+
 	if (enable) {
 		/* Disable hardware flow control */
 		ktermios = tty->termios;
-- 
2.17.1

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Johan Hovold]

On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> tiocmget() and tiocmset() operations are optional and some tty drivers
> like pty miss the operations. We need NULL check to prevent from
> dereference.
> 
> Signed-off-by: Myungho Jung <mhjungk@gmail.com>
> ---
>  drivers/bluetooth/hci_ath.c   | 6 ++++++
>  drivers/bluetooth/hci_ldisc.c | 4 ++++
>  2 files changed, 10 insertions(+)

Ah, you had already submitted a v2.

I still suggest splitting this one in two patches and that you add a
Fixes and stable tag to each so that they both get backported to stable.

Also, when resubmitting, make sure to include a short changelog here
below the cut-off line (---).

> 
> diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> index d568fbd94d6c..fb9f6323a911 100644
> --- a/drivers/bluetooth/hci_ath.c
> +++ b/drivers/bluetooth/hci_ath.c
> @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
>  
>  static int ath_setup(struct hci_uart *hu)
>  {
> +	struct tty_struct *tty = hu->tty;
> +
>  	BT_DBG("hu %p", hu);
>  
> +	/* tty driver should support operations to set RTS */
> +	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> +		return -EOPNOTSUPP;

-ENODEV might be more appropriate.

Johan

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Myungho Jung]

On Thu, Jan 31, 2019 at 04:40:00PM +0100, Johan Hovold wrote:
> On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> > tiocmget() and tiocmset() operations are optional and some tty drivers
> > like pty miss the operations. We need NULL check to prevent from
> > dereference.
> > 
> > Signed-off-by: Myungho Jung <mhjungk@gmail.com>
> > ---
> >  drivers/bluetooth/hci_ath.c   | 6 ++++++
> >  drivers/bluetooth/hci_ldisc.c | 4 ++++
> >  2 files changed, 10 insertions(+)
> 
> Ah, you had already submitted a v2.
> 
> I still suggest splitting this one in two patches and that you add a
> Fixes and stable tag to each so that they both get backported to stable.
> 
> Also, when resubmitting, make sure to include a short changelog here
> below the cut-off line (---).
> 
> > 
> > diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> > index d568fbd94d6c..fb9f6323a911 100644
> > --- a/drivers/bluetooth/hci_ath.c
> > +++ b/drivers/bluetooth/hci_ath.c
> > @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> >  
> >  static int ath_setup(struct hci_uart *hu)
> >  {
> > +	struct tty_struct *tty = hu->tty;
> > +
> >  	BT_DBG("hu %p", hu);
> >  
> > +	/* tty driver should support operations to set RTS */
> > +	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> > +		return -EOPNOTSUPP;
> 
> -ENODEV might be more appropriate.
> 
> Johan

I'll split into 2 seperate patches. So, do I need to add stable tag on each
patch like below to be cherry-picked?

Cc: <stable@vger.kernel.org> # <hash>: <summary>

I looked for a good example from mailing list but didn't find one.

Thanks,
Myungho

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Johan Hovold]

On Sat, Feb 02, 2019 at 10:38:24PM -0800, Myungho Jung wrote:
> On Thu, Jan 31, 2019 at 04:40:00PM +0100, Johan Hovold wrote:
> > On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> > > tiocmget() and tiocmset() operations are optional and some tty drivers
> > > like pty miss the operations. We need NULL check to prevent from
> > > dereference.
> > > 
> > > Signed-off-by: Myungho Jung <mhjungk@gmail.com>
> > > ---
> > >  drivers/bluetooth/hci_ath.c   | 6 ++++++
> > >  drivers/bluetooth/hci_ldisc.c | 4 ++++
> > >  2 files changed, 10 insertions(+)
> > 
> > Ah, you had already submitted a v2.
> > 
> > I still suggest splitting this one in two patches and that you add a
> > Fixes and stable tag to each so that they both get backported to stable.
> > 
> > Also, when resubmitting, make sure to include a short changelog here
> > below the cut-off line (---).
> > 
> > > 
> > > diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> > > index d568fbd94d6c..fb9f6323a911 100644
> > > --- a/drivers/bluetooth/hci_ath.c
> > > +++ b/drivers/bluetooth/hci_ath.c
> > > @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> > >  
> > >  static int ath_setup(struct hci_uart *hu)
> > >  {
> > > +	struct tty_struct *tty = hu->tty;
> > > +
> > >  	BT_DBG("hu %p", hu);
> > >  
> > > +	/* tty driver should support operations to set RTS */
> > > +	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> > > +		return -EOPNOTSUPP;
> > 
> > -ENODEV might be more appropriate.
> > 
> > Johan
> 
> I'll split into 2 seperate patches. So, do I need to add stable tag on each
> patch like below to be cherry-picked?
> 
> Cc: <stable@vger.kernel.org> # <hash>: <summary>
> 
> I looked for a good example from mailing list but didn't find one.

Almost right, the format you use above is actually used to identify
dependencies for backports.

You should add a Fixes tag identifying the commit which introduced each
bug and a stable-cc tag. If you want you can indicate the version after
a # sign, but that can also be inferred from the fixes tag.

For the hci_ldisc fix I think the tags would be:

	Fixes: 2a973dfada2b ("Bluetooth: hci_uart: Add new line discipline enhancements")
	Cc: stable <stable@vger.kernel.org>     # 4.2

You can use git blame to track down the offending commits.

This should all be explained here:

	https://www.kernel.org/doc/html/latest/process/submitting-patches.html

Johan

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Myungho Jung]

On Sun, Feb 03, 2019 at 11:53:23AM +0100, Johan Hovold wrote:
> On Sat, Feb 02, 2019 at 10:38:24PM -0800, Myungho Jung wrote:
> > On Thu, Jan 31, 2019 at 04:40:00PM +0100, Johan Hovold wrote:
> > > On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> > > > tiocmget() and tiocmset() operations are optional and some tty drivers
> > > > like pty miss the operations. We need NULL check to prevent from
> > > > dereference.
> > > > 
> > > > Signed-off-by: Myungho Jung <mhjungk@gmail.com>
> > > > ---
> > > >  drivers/bluetooth/hci_ath.c   | 6 ++++++
> > > >  drivers/bluetooth/hci_ldisc.c | 4 ++++
> > > >  2 files changed, 10 insertions(+)
> > > 
> > > Ah, you had already submitted a v2.
> > > 
> > > I still suggest splitting this one in two patches and that you add a
> > > Fixes and stable tag to each so that they both get backported to stable.
> > > 
> > > Also, when resubmitting, make sure to include a short changelog here
> > > below the cut-off line (---).
> > > 
> > > > 
> > > > diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> > > > index d568fbd94d6c..fb9f6323a911 100644
> > > > --- a/drivers/bluetooth/hci_ath.c
> > > > +++ b/drivers/bluetooth/hci_ath.c
> > > > @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> > > >  
> > > >  static int ath_setup(struct hci_uart *hu)
> > > >  {
> > > > +	struct tty_struct *tty = hu->tty;
> > > > +
> > > >  	BT_DBG("hu %p", hu);
> > > >  
> > > > +	/* tty driver should support operations to set RTS */
> > > > +	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> > > > +		return -EOPNOTSUPP;
> > > 
> > > -ENODEV might be more appropriate.
> > > 
> > > Johan
> > 
> > I'll split into 2 seperate patches. So, do I need to add stable tag on each
> > patch like below to be cherry-picked?
> > 
> > Cc: <stable@vger.kernel.org> # <hash>: <summary>
> > 
> > I looked for a good example from mailing list but didn't find one.
> 
> Almost right, the format you use above is actually used to identify
> dependencies for backports.
> 
> You should add a Fixes tag identifying the commit which introduced each
> bug and a stable-cc tag. If you want you can indicate the version after
> a # sign, but that can also be inferred from the fixes tag.
> 
> For the hci_ldisc fix I think the tags would be:
> 
> 	Fixes: 2a973dfada2b ("Bluetooth: hci_uart: Add new line discipline enhancements")
> 	Cc: stable <stable@vger.kernel.org>     # 4.2
> 
> You can use git blame to track down the offending commits.
> 
> This should all be explained here:
> 
> 	https://www.kernel.org/doc/html/latest/process/submitting-patches.html
> 
> Johan

Thank you for the explanation. I'll carefully read the page and submit the next
patch.

Thanks,
Myungho

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Myungho Jung]

On Sun, Feb 03, 2019 at 11:29:00PM -0800, Myungho Jung wrote:
> On Sun, Feb 03, 2019 at 11:53:23AM +0100, Johan Hovold wrote:
> > On Sat, Feb 02, 2019 at 10:38:24PM -0800, Myungho Jung wrote:
> > > On Thu, Jan 31, 2019 at 04:40:00PM +0100, Johan Hovold wrote:
> > > > On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> > > > > tiocmget() and tiocmset() operations are optional and some tty drivers
> > > > > like pty miss the operations. We need NULL check to prevent from
> > > > > dereference.
> > > > > 
> > > > > Signed-off-by: Myungho Jung <mhjungk@gmail.com>
> > > > > ---
> > > > >  drivers/bluetooth/hci_ath.c   | 6 ++++++
> > > > >  drivers/bluetooth/hci_ldisc.c | 4 ++++
> > > > >  2 files changed, 10 insertions(+)
> > > > 
> > > > Ah, you had already submitted a v2.
> > > > 
> > > > I still suggest splitting this one in two patches and that you add a
> > > > Fixes and stable tag to each so that they both get backported to stable.
> > > > 
> > > > Also, when resubmitting, make sure to include a short changelog here
> > > > below the cut-off line (---).
> > > > 
> > > > > 
> > > > > diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> > > > > index d568fbd94d6c..fb9f6323a911 100644
> > > > > --- a/drivers/bluetooth/hci_ath.c
> > > > > +++ b/drivers/bluetooth/hci_ath.c
> > > > > @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> > > > >  
> > > > >  static int ath_setup(struct hci_uart *hu)
> > > > >  {
> > > > > +	struct tty_struct *tty = hu->tty;
> > > > > +
> > > > >  	BT_DBG("hu %p", hu);
> > > > >  
> > > > > +	/* tty driver should support operations to set RTS */
> > > > > +	if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> > > > > +		return -EOPNOTSUPP;
> > > > 
> > > > -ENODEV might be more appropriate.
> > > > 
> > > > Johan
> > > 
> > > I'll split into 2 seperate patches. So, do I need to add stable tag on each
> > > patch like below to be cherry-picked?
> > > 
> > > Cc: <stable@vger.kernel.org> # <hash>: <summary>
> > > 
> > > I looked for a good example from mailing list but didn't find one.
> > 
> > Almost right, the format you use above is actually used to identify
> > dependencies for backports.
> > 
> > You should add a Fixes tag identifying the commit which introduced each
> > bug and a stable-cc tag. If you want you can indicate the version after
> > a # sign, but that can also be inferred from the fixes tag.
> > 
> > For the hci_ldisc fix I think the tags would be:
> > 
> > 	Fixes: 2a973dfada2b ("Bluetooth: hci_uart: Add new line discipline enhancements")
> > 	Cc: stable <stable@vger.kernel.org>     # 4.2
> > 
> > You can use git blame to track down the offending commits.
> > 
> > This should all be explained here:
> > 
> > 	https://www.kernel.org/doc/html/latest/process/submitting-patches.html
> > 
> > Johan
> 
> Thank you for the explanation. I'll carefully read the page and submit the next
> patch.
> 
> Thanks,
> Myungho

Hi Johan,

I have one more question. The title of new patches should be version 3 like
this?
[PATCH v3] Bluetooth: hci_ath: ...
[PATCH v3] Bluetooth: hci_ldisc: ...

Or newly start with [PATCH]?

Thanks,
Myungho

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Johan Hovold]

On Mon, Feb 04, 2019 at 01:04:37AM -0800, Myungho Jung wrote:
> On Sun, Feb 03, 2019 at 11:29:00PM -0800, Myungho Jung wrote:
> > On Sun, Feb 03, 2019 at 11:53:23AM +0100, Johan Hovold wrote:

> > > You should add a Fixes tag identifying the commit which introduced each
> > > bug and a stable-cc tag. If you want you can indicate the version after
> > > a # sign, but that can also be inferred from the fixes tag.
> > > 
> > > For the hci_ldisc fix I think the tags would be:
> > > 
> > > 	Fixes: 2a973dfada2b ("Bluetooth: hci_uart: Add new line discipline enhancements")
> > > 	Cc: stable <stable@vger.kernel.org>     # 4.2
> > > 
> > > You can use git blame to track down the offending commits.
> > > 
> > > This should all be explained here:
> > > 
> > > 	https://www.kernel.org/doc/html/latest/process/submitting-patches.html

> I have one more question. The title of new patches should be version 3 like
> this?
> [PATCH v3] Bluetooth: hci_ath: ...
> [PATCH v3] Bluetooth: hci_ldisc: ...
> 
> Or newly start with [PATCH]?

You should keep and increment the revision number even if you split a
patch (so use v3 for the resend).

I suggest you send both patches in a series (as they are related); take
a look at git-send-email for a convenient way to do that. 

And always include a brief changelog (below the cut-off line, "---")
when revising patches.

Johan

Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

[Myungho Jung]

On Mon, Feb 04, 2019 at 10:22:16AM +0100, Johan Hovold wrote:
> On Mon, Feb 04, 2019 at 01:04:37AM -0800, Myungho Jung wrote:
> > On Sun, Feb 03, 2019 at 11:29:00PM -0800, Myungho Jung wrote:
> > > On Sun, Feb 03, 2019 at 11:53:23AM +0100, Johan Hovold wrote:
> 
> > > > You should add a Fixes tag identifying the commit which introduced each
> > > > bug and a stable-cc tag. If you want you can indicate the version after
> > > > a # sign, but that can also be inferred from the fixes tag.
> > > > 
> > > > For the hci_ldisc fix I think the tags would be:
> > > > 
> > > > 	Fixes: 2a973dfada2b ("Bluetooth: hci_uart: Add new line discipline enhancements")
> > > > 	Cc: stable <stable@vger.kernel.org>     # 4.2
> > > > 
> > > > You can use git blame to track down the offending commits.
> > > > 
> > > > This should all be explained here:
> > > > 
> > > > 	https://www.kernel.org/doc/html/latest/process/submitting-patches.html
> 
> > I have one more question. The title of new patches should be version 3 like
> > this?
> > [PATCH v3] Bluetooth: hci_ath: ...
> > [PATCH v3] Bluetooth: hci_ldisc: ...
> > 
> > Or newly start with [PATCH]?
> 
> You should keep and increment the revision number even if you split a
> patch (so use v3 for the resend).
> 
> I suggest you send both patches in a series (as they are related); take
> a look at git-send-email for a convenient way to do that. 
> 
> And always include a brief changelog (below the cut-off line, "---")
> when revising patches.
> 
> Johan

I see. I'll submit version 3 as a patchset with change logs.

Thanks,
Myungho