Re: [PATCH net v2] net: mdio-ipq4019: fix possible invalid pointer dereference

[Hui Tang]

On 2022/11/21 22:36, Andrew Lunn wrote:
> > Hi, Andrew
> >
> > My new patchset is ready, but I just found out that another patch has been
> > applied to netdev/net.git. Can I solve the problem in present way? And I
> > will add devm_ioremap_resource_optional() helper later to optimize related
> > drivers. How about this?
>
> This is one of those harder to merge changes. patches to lib/devres.c
> generally go via GregKH. Networking changes are merged via the netdev
> list.
>
> Did you find this issue via a static analyser? I assume you are
> running it over the entire tree and are finding problems in multiple
> subsystems? So devm_ioremap_resource_optional() is potentially going
> to be needed in lots of places?

Yes, I grep the entire drives, some drivers is really going to
be needed for devm_ioremap_resource_optional() case.

For example:

drivers/mmc/host/mtk-sd.c
drivers/mmc/host/sdhci-st.c
drivers/ufs/host/ufs-qcom.c
drivers/mfd/bcm2835-pm.c
net/mdio/mdio-ipq4019.c
drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c

> One way to get this merged is to cross post the patch adding
> devm_ioremap_resource_optional() and ask GregKH to ACK it, and then
> get netdev to merge it. You can then use it within the netdev
> subsystem. What you cannot do is use it in other subsystems until the
> next kernel cycle when it will be globally available.
>
> So three patches. One adding devm_ioremap_resource_optional(), one to
> revert the 'fix', and one with the real fix using
> devm_ioremap_resource_optional().

Thanks