Re: [PATCH] KEYS: prevent NULL pointer dereference in find_asymmetric_key()

[Jarkko Sakkinen]

On Tue Mar 19, 2024 at 4:44 PM EET, Roman Smirnov wrote:
> On Tue, 19 Mar 2024 01:39:00 +0200 Jarkko Sakkinen wrote:
> > On Fri Mar 15, 2024 at 12:33 PM EET, Roman Smirnov wrote:
> > > With the current code, in case all NULLs are passed in id_{0,1,2},
> > 
> > "current code" is not unambigious reference of any part of the kernel
> > tree. Please just write down the function name instead.
> > 
> > > the kernel will first print out a WARNING and then have an oops
> > > because id_2 gets dereferenced anyway.
> > 
> > Would be more exact":
> > 
> > s/print out a WARNING/emit WARN/
>
> Okay, I'll prepare a second version of the patch.
>
> > > Note that WARN_ON() is also considered harmful by Greg Kroah-
> > > Hartman since it causes the Android kernels to panic as they
> > > get booted with the panic_on_warn option.
> > 
> > Despite full respect to Greg, and agreeing what he had said about
> > the topic (which you are lacking lore link meaning that in all
> > cases the current description is incomplete), the only thing that
> > should be documented should be that since WARN_ON() can emit
> > panic when panic_on_warn is set in the *kernel command-line*
> > (not "option") this condition should be relaxed.
>
> Here's a link to the discussion:
> https://lore.kernel.org/all/2024011213-situated-augmented-64a4@gregkh/
> From the context, I thought WARN_ON() would be better removed.

Not sure what you are trying to claim here that goes against what I
just said.

>
> > >
> > > Found by Linux Verification Center (linuxtesting.org) with Svace.
> > 
> > I'm not sure if this should be part of the commit message.
>
> I have already submitted patches with this line, some have been
> accepted. It is important for the Linux Verification Center to mark
> patches as closing issues found with Svace.
>
> > >
> > > Fixes: 7d30198ee24f ("keys: X.509 public key issuer lookup without AKID")
> > > Suggested-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
> > 
> > Should be reported-by.
>
> The suggested-by tag belongs to Sergey because he suggested the fix,
> subject/description of the patch. The tag reported-by belongs to
> Svace tool.

1. I did not see any reported-by tags in this which is requirement.
2. Who did find the issue using that tool? I don't put reported-by to
   GDB even if I use that find the bug.
>
> Thank you for the reply.


BR, Jarkko