Re: [PATCH 02/12] bus: fsl-mc: use generic driver_override infrastructure

["Christophe Leroy (CS GROUP)" <chleroy@xxxxxxxxxx>]

Le 28/03/2026 à 13:10, Christophe Leroy (CS GROUP) a écrit :
> Le 25/03/2026 à 13:01, Ioana Ciornei a écrit :
> > On Tue, Mar 24, 2026 at 01:59:06AM +0100, Danilo Krummrich wrote:
> > > When a driver is probed through __driver_attach(), the bus' match()
> > > callback is called without the device lock held, thus accessing the
> > > driver_override field without a lock, which can cause a UAF.
> > >
> > > Fix this by using the driver-core driver_override infrastructure taking
> > > care of proper locking internally.
> > >
> > > Note that calling match() from __driver_attach() without the device lock
> > > held is intentional. [1]
> > >
> > > Link: https://eur01.safelinks.protection.outlook.com/? 
> > > url=https%3A%2F%2Flore.kernel.org%2Fdriver- 
> > > core%2FDGRGTIRHA62X.3RY09D9SOK77P%40kernel.org%2F&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C4b9262ddecdd4ce29f9808de8a66485e%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639100369055903282%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=%2BRfjlUkq7oWV%2F0v2S2B%2BEuxCY%2FLRQv6qHiEWiupd6kc%3D&reserved=0 [1]
> > > Reported-by: Gui-Dong Han <hanguidong02@xxxxxxxxx>
> > > Closes: https://eur01.safelinks.protection.outlook.com/? 
> > > url=https%3A%2F%2Fbugzilla.kernel.org%2Fshow_bug.cgi%3Fid%3D220789&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C4b9262ddecdd4ce29f9808de8a66485e%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639100369055936232%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=XL1K1ICiygOZnlvDUbQFe192KnLsBQms0HFNGCuyz%2Fw%3D&reserved=0
> > > Fixes: 1f86a00c1159 ("bus/fsl-mc: add support for 'driver_override' 
> > > in the mc-bus")
> > > Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
> > Tested-by: Ioana Ciornei <ioana.ciornei@xxxxxxx>
> > Signed-off-by: Ioana Ciornei <ioana.ciornei@xxxxxxx>
>
> Applied, thanks
Have to drop it for now, build fails:

  CALL    scripts/checksyscalls.sh
  CC      drivers/bus/fsl-mc/fsl-mc-bus.o
drivers/bus/fsl-mc/fsl-mc-bus.c: In function 'fsl_mc_bus_match':
drivers/bus/fsl-mc/fsl-mc-bus.c:92:15: error: implicit declaration of 
function 'device_match_driver_override' 
[-Werror=implicit-function-declaration]
   92 |         ret = device_match_driver_override(dev, drv);
      |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/bus/fsl-mc/fsl-mc-bus.c: At top level:
drivers/bus/fsl-mc/fsl-mc-bus.c:321:10: error: 'const struct bus_type' 
has no member named 'driver_override'
  321 |         .driver_override = true,
      |          ^~~~~~~~~~~~~~~
drivers/bus/fsl-mc/fsl-mc-bus.c:321:28: warning: initialization of 
'const char *' from 'int' makes pointer from integer without a cast 
[-Wint-conversion]
  321 |         .driver_override = true,
      |                            ^~~~
drivers/bus/fsl-mc/fsl-mc-bus.c:321:28: note: (near initialization for 
'fsl_mc_bus_type.dev_name')
cc1: some warnings being treated as errors
make[5]: *** [scripts/Makefile.build:289: 
drivers/bus/fsl-mc/fsl-mc-bus.o] Error 1
make[4]: *** [scripts/Makefile.build:546: drivers/bus/fsl-mc] Error 2
make[3]: *** [scripts/Makefile.build:546: drivers/bus] Error 2
make[2]: *** [scripts/Makefile.build:546: drivers] Error 2
make[1]: *** [/home/chleroy/linux-powerpc/Makefile:2101: .] Error 2
make: *** [Makefile:248: __sub-make] Error 2

Christophe