All of lore.kernel.org
 help / color / mirror / Atom feed
From: Lee Jones <lee.jones@linaro.org>
To: Daniel Thompson <daniel.thompson@linaro.org>
Cc: baohua@kernel.org, stephan@gerhold.net, arnd@arndb.de,
	linus.walleij@linaro.org, linux-kernel@vger.kernel.org,
	broonie@kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 7/9] mfd: mfd-core: Protect against NULL call-back function pointer
Date: Mon, 21 Oct 2019 13:40:27 +0100	[thread overview]
Message-ID: <20191021124027.GG4365@dell> (raw)
In-Reply-To: <20191021123235.royyfp4mxrvsgioh@holly.lan>

On Mon, 21 Oct 2019, Daniel Thompson wrote:

> On Mon, Oct 21, 2019 at 11:58:20AM +0100, Lee Jones wrote:
> > If a child device calls mfd_cell_{en,dis}able() without an appropriate
> > call-back being set, we are likely to encounter a panic.  Avoid this
> > by adding suitable checking.
> > 
> > Signed-off-by: Lee Jones <lee.jones@linaro.org>
> > ---
> >  drivers/mfd/mfd-core.c | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
> > index 8126665bb2d8..90b43b44a15a 100644
> > --- a/drivers/mfd/mfd-core.c
> > +++ b/drivers/mfd/mfd-core.c
> > @@ -28,6 +28,11 @@ int mfd_cell_enable(struct platform_device *pdev)
> >  	const struct mfd_cell *cell = mfd_get_cell(pdev);
> >  	int err = 0;
> >  
> > +	if (!cell->enable) {
> > +		dev_dbg(&pdev->dev, "No .enable() call-back registered\n");
> > +		return 0;
> > +	}
> > +
> >  	/* only call enable hook if the cell wasn't previously enabled */
> >  	if (atomic_inc_return(cell->usage_count) == 1)
> >  		err = cell->enable(pdev);
> > @@ -45,6 +50,11 @@ int mfd_cell_disable(struct platform_device *pdev)
> >  	const struct mfd_cell *cell = mfd_get_cell(pdev);
> >  	int err = 0;
> >  
> > +	if (!cell->enable) {
> 
> Oops.
> 
> Cancel the R-B: ;-). Shouldn't this be !cell->disable() ?

Yes. Looks like a C/P error.

Will fix and add your R-b.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

WARNING: multiple messages have this Message-ID (diff)
From: Lee Jones <lee.jones@linaro.org>
To: Daniel Thompson <daniel.thompson@linaro.org>
Cc: arnd@arndb.de, broonie@kernel.org, linus.walleij@linaro.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, baohua@kernel.org,
	stephan@gerhold.net
Subject: Re: [PATCH v2 7/9] mfd: mfd-core: Protect against NULL call-back function pointer
Date: Mon, 21 Oct 2019 13:40:27 +0100	[thread overview]
Message-ID: <20191021124027.GG4365@dell> (raw)
In-Reply-To: <20191021123235.royyfp4mxrvsgioh@holly.lan>

On Mon, 21 Oct 2019, Daniel Thompson wrote:

> On Mon, Oct 21, 2019 at 11:58:20AM +0100, Lee Jones wrote:
> > If a child device calls mfd_cell_{en,dis}able() without an appropriate
> > call-back being set, we are likely to encounter a panic.  Avoid this
> > by adding suitable checking.
> > 
> > Signed-off-by: Lee Jones <lee.jones@linaro.org>
> > ---
> >  drivers/mfd/mfd-core.c | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
> > index 8126665bb2d8..90b43b44a15a 100644
> > --- a/drivers/mfd/mfd-core.c
> > +++ b/drivers/mfd/mfd-core.c
> > @@ -28,6 +28,11 @@ int mfd_cell_enable(struct platform_device *pdev)
> >  	const struct mfd_cell *cell = mfd_get_cell(pdev);
> >  	int err = 0;
> >  
> > +	if (!cell->enable) {
> > +		dev_dbg(&pdev->dev, "No .enable() call-back registered\n");
> > +		return 0;
> > +	}
> > +
> >  	/* only call enable hook if the cell wasn't previously enabled */
> >  	if (atomic_inc_return(cell->usage_count) == 1)
> >  		err = cell->enable(pdev);
> > @@ -45,6 +50,11 @@ int mfd_cell_disable(struct platform_device *pdev)
> >  	const struct mfd_cell *cell = mfd_get_cell(pdev);
> >  	int err = 0;
> >  
> > +	if (!cell->enable) {
> 
> Oops.
> 
> Cancel the R-B: ;-). Shouldn't this be !cell->disable() ?

Yes. Looks like a C/P error.

Will fix and add your R-b.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

  reply	other threads:[~2019-10-21 12:40 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-21 10:58 [PATCH v2 0/9] Simplify MFD Core Lee Jones
2019-10-21 10:58 ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 1/9] mfd: cs5535-mfd: Use PLATFORM_DEVID_* defines and tidy error message Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 11:15   ` Daniel Thompson
2019-10-21 11:15     ` Daniel Thompson
2019-10-21 11:33     ` Lee Jones
2019-10-21 11:33       ` Lee Jones
2019-10-21 11:35       ` Lee Jones
2019-10-21 11:35         ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 2/9] mfd: cs5535-mfd: Remove mfd_cell->id hack Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 11:11   ` Daniel Thompson
2019-10-21 11:11     ` Daniel Thompson
2019-10-21 11:46     ` Lee Jones
2019-10-21 11:46       ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 3/9] mfd: cs5535-mfd: Request shared IO regions centrally Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:26   ` Daniel Thompson
2019-10-21 12:26     ` Daniel Thompson
2019-10-21 12:46     ` Lee Jones
2019-10-21 12:46       ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 4/9] mfd: cs5535-mfd: Register clients using their own dedicated MFD cell entries Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:29   ` Daniel Thompson
2019-10-21 12:29     ` Daniel Thompson
2019-10-21 13:21     ` Lee Jones
2019-10-21 13:21       ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 5/9] mfd: mfd-core: Remove mfd_clone_cell() Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:29   ` Daniel Thompson
2019-10-21 12:29     ` Daniel Thompson
2019-10-21 10:58 ` [PATCH v2 6/9] x86: olpc: Remove invocation of MFD's .enable()/.disable() call-backs Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:17   ` Daniel Thompson
2019-10-21 12:17     ` Daniel Thompson
2019-10-21 10:58 ` [PATCH v2 7/9] mfd: mfd-core: Protect against NULL call-back function pointer Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:30   ` Daniel Thompson
2019-10-21 12:30     ` Daniel Thompson
2019-10-21 12:32   ` Daniel Thompson
2019-10-21 12:32     ` Daniel Thompson
2019-10-21 12:40     ` Lee Jones [this message]
2019-10-21 12:40       ` Lee Jones
2019-10-21 10:58 ` [PATCH v2 8/9] mfd: mfd-core: Remove usage counting for .{en, dis}able() call-backs Lee Jones
2019-10-21 10:58   ` [PATCH v2 8/9] mfd: mfd-core: Remove usage counting for .{en,dis}able() call-backs Lee Jones
2019-10-21 12:33   ` Daniel Thompson
2019-10-21 12:33     ` Daniel Thompson
2019-10-21 10:58 ` [PATCH v2 9/9] mfd: mfd-core: Move pdev->mfd_cell creation back into mfd_add_device() Lee Jones
2019-10-21 10:58   ` Lee Jones
2019-10-21 12:45   ` Daniel Thompson
2019-10-21 12:45     ` Daniel Thompson
2019-10-21 11:29 ` [PATCH v2 0/9] Simplify MFD Core Arnd Bergmann
2019-10-21 11:29   ` Arnd Bergmann
2019-10-21 11:39   ` Lee Jones
2019-10-21 11:39     ` Lee Jones
2019-10-21 11:44   ` Lubomir Rintel
2019-10-21 11:44     ` Lubomir Rintel
2019-10-21 11:53     ` Lee Jones
2019-10-21 11:53       ` Lee Jones
2019-10-21 12:21       ` Lubomir Rintel
2019-10-21 12:21         ` Lubomir Rintel
2019-10-21 13:01         ` Lee Jones
2019-10-21 13:01           ` Lee Jones
2019-11-01  9:07         ` Lee Jones
2019-11-01  9:07           ` Lee Jones
2019-11-01 15:01           ` Lubomir Rintel
2019-11-01 15:01             ` Lubomir Rintel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191021124027.GG4365@dell \
    --to=lee.jones@linaro.org \
    --cc=arnd@arndb.de \
    --cc=baohua@kernel.org \
    --cc=broonie@kernel.org \
    --cc=daniel.thompson@linaro.org \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=stephan@gerhold.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.