* [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn()
@ 2020-08-17 23:50 Dmitry Osipenko
2020-08-21 14:46 ` Lee Jones
[not found] ` <CGME20200824083847eucas1p2e5fee0790df8f21934d99e848dc14afe@eucas1p2.samsung.com>
0 siblings, 2 replies; 4+ messages in thread
From: Dmitry Osipenko @ 2020-08-17 23:50 UTC (permalink / raw)
To: Lee Jones; +Cc: linux-kernel
The pdev.mfd_cell is released by platform_device_release(), which is
invoked by platform_device_unregister(). Hence mfd_remove_devices_fn()
shouldn't release the cell variable. The double-free bug is reported KASAN
during of MFD driver module removal.
Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/mfd/mfd-core.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
index c3651f06684f..c50718e3db58 100644
--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -370,8 +370,6 @@ static int mfd_remove_devices_fn(struct device *dev, void *data)
regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
cell->num_parent_supplies);
- kfree(cell);
-
platform_device_unregister(pdev);
return 0;
}
--
2.27.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn()
2020-08-17 23:50 [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn() Dmitry Osipenko
@ 2020-08-21 14:46 ` Lee Jones
[not found] ` <CGME20200824083847eucas1p2e5fee0790df8f21934d99e848dc14afe@eucas1p2.samsung.com>
1 sibling, 0 replies; 4+ messages in thread
From: Lee Jones @ 2020-08-21 14:46 UTC (permalink / raw)
To: Dmitry Osipenko; +Cc: linux-kernel
On Tue, 18 Aug 2020, Dmitry Osipenko wrote:
> The pdev.mfd_cell is released by platform_device_release(), which is
> invoked by platform_device_unregister(). Hence mfd_remove_devices_fn()
> shouldn't release the cell variable. The double-free bug is reported KASAN
> during of MFD driver module removal.
>
> Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes")
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
> drivers/mfd/mfd-core.c | 2 --
> 1 file changed, 2 deletions(-)
Applied, thanks.
--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn()
[not found] ` <CGME20200824083847eucas1p2e5fee0790df8f21934d99e848dc14afe@eucas1p2.samsung.com>
@ 2020-08-24 8:38 ` Marek Szyprowski
2020-08-24 8:49 ` Lee Jones
0 siblings, 1 reply; 4+ messages in thread
From: Marek Szyprowski @ 2020-08-24 8:38 UTC (permalink / raw)
To: Dmitry Osipenko, Lee Jones; +Cc: linux-kernel
Hi
On 18.08.2020 01:50, Dmitry Osipenko wrote:
> The pdev.mfd_cell is released by platform_device_release(), which is
> invoked by platform_device_unregister(). Hence mfd_remove_devices_fn()
> shouldn't release the cell variable. The double-free bug is reported KASAN
> during of MFD driver module removal.
>
> Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes")
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
I've reported that almost a week earlier and got information that it
will be dropped:
https://lore.kernel.org/lkml/79bcd1b5-2247-5e00-7d49-2f94f9b40744@samsung.com/
https://lore.kernel.org/lkml/20200813080100.GI4354@dell/
Sadly it finally landed in v5.9-rc1. Would be nice to mention this in
the revert:
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
> drivers/mfd/mfd-core.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
> index c3651f06684f..c50718e3db58 100644
> --- a/drivers/mfd/mfd-core.c
> +++ b/drivers/mfd/mfd-core.c
> @@ -370,8 +370,6 @@ static int mfd_remove_devices_fn(struct device *dev, void *data)
> regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
> cell->num_parent_supplies);
>
> - kfree(cell);
> -
> platform_device_unregister(pdev);
> return 0;
> }
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn()
2020-08-24 8:38 ` Marek Szyprowski
@ 2020-08-24 8:49 ` Lee Jones
0 siblings, 0 replies; 4+ messages in thread
From: Lee Jones @ 2020-08-24 8:49 UTC (permalink / raw)
To: Marek Szyprowski; +Cc: Dmitry Osipenko, linux-kernel
On Mon, 24 Aug 2020, Marek Szyprowski wrote:
> Hi
>
> On 18.08.2020 01:50, Dmitry Osipenko wrote:
> > The pdev.mfd_cell is released by platform_device_release(), which is
> > invoked by platform_device_unregister(). Hence mfd_remove_devices_fn()
> > shouldn't release the cell variable. The double-free bug is reported KASAN
> > during of MFD driver module removal.
> >
> > Fixes: 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes")
> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> > ---
>
> I've reported that almost a week earlier and got information that it
> will be dropped:
>
> https://lore.kernel.org/lkml/79bcd1b5-2247-5e00-7d49-2f94f9b40744@samsung.com/
>
> https://lore.kernel.org/lkml/20200813080100.GI4354@dell/
>
> Sadly it finally landed in v5.9-rc1. Would be nice to mention this in
> the revert:
That's true. The patch was taken out but the change managed to get in
via another commit. I will add your Reported-by to the revert.
> Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
>
> > drivers/mfd/mfd-core.c | 2 --
> > 1 file changed, 2 deletions(-)
> >
> > diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
> > index c3651f06684f..c50718e3db58 100644
> > --- a/drivers/mfd/mfd-core.c
> > +++ b/drivers/mfd/mfd-core.c
> > @@ -370,8 +370,6 @@ static int mfd_remove_devices_fn(struct device *dev, void *data)
> > regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
> > cell->num_parent_supplies);
> >
> > - kfree(cell);
> > -
> > platform_device_unregister(pdev);
> > return 0;
> > }
>
> Best regards
--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-08-24 9:51 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-17 23:50 [PATCH v1] mfd: core: Fix double-free in mfd_remove_devices_fn() Dmitry Osipenko
2020-08-21 14:46 ` Lee Jones
[not found] ` <CGME20200824083847eucas1p2e5fee0790df8f21934d99e848dc14afe@eucas1p2.samsung.com>
2020-08-24 8:38 ` Marek Szyprowski
2020-08-24 8:49 ` Lee Jones
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).