Re: [PATCH v2] relay: handle alloc_percpu returning NULL in relay_open

[Michael Ellerman]

[ + akpm ]

Daniel Axtens <dja@xxxxxxxxxx> writes:
>>> > Check if alloc_percpu returns NULL.
>>> > 
>>> > This was found by syzkaller both on x86 and powerpc, and the reproducer
>>> > it found on powerpc is capable of hitting the issue as an unprivileged
>>> > user.
>>> > 
>>> > Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers")
>>> > Reported-by: syzbot+1e925b4b836afe85a1c6@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>>> > Reported-by: syzbot+587b2421926808309d21@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>>> > Reported-by: syzbot+58320b7171734bf79d26@xxxxxxxxxxxxxxxxxxxxxxxxx
>>> > Reported-by: syzbot+d6074fb08bdb2e010520@xxxxxxxxxxxxxxxxxxxxxxxxx
>>> > Cc: Akash Goel <akash.goel@xxxxxxxxx>
>>> > Cc: Andrew Donnellan <ajd@xxxxxxxxxxxxx> # syzkaller-ppc64
>>> > Reviewed-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
>>> > Reviewed-by: Andrew Donnellan <ajd@xxxxxxxxxxxxx>
>>> > Cc: stable@xxxxxxxxxxxxxxx # v4.10+
>>> > Signed-off-by: Daniel Axtens <dja@xxxxxxxxxx>
>>> 
>>> Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
>>
>> It looks this one was never applied (which relates to CVE-2019-19462,
>> as pointed by Guenter in 20191223163610.GA32267@xxxxxxxxxxxx).
>>
>> Whas this lost or are there any issues pending?
>
> I'm not aware of any pending issues.
>
> (But, if anyone does have any objections I'm happy to revise the patch.)

It looks like kernel/relay.c is lacking a maintainer?

Andrew are you able to pick this up for v5.8? It's pretty obviously
correct, and has David's ack.

Original is here if that helps:
  https://lore.kernel.org/lkml/20191219121256.26480-1-dja@xxxxxxxxxx/


cheers