Re: [PATCH 2/2] [net-next] bpf: fix out-of-bounds access warning in bpf_check

From: David Miller
Date: Fri Nov 03 2017 - 01:20:57 EST


From: Arnd Bergmann <arnd@xxxxxxxx>
Date: Thu, 2 Nov 2017 12:05:52 +0100

> The bpf_verifer_ops array is generated dynamically and may be
> empty depending on configuration, which then causes an out
> of bounds access:
>
> kernel/bpf/verifier.c: In function 'bpf_check':
> kernel/bpf/verifier.c:4320:29: error: array subscript is above array bounds [-Werror=array-bounds]
>
> This adds a check to the start of the function as a workaround.
> I would assume that the function is never called in that configuration,
> so the warning is probably harmless.
>
> Fixes: 00176a34d9e2 ("bpf: remove the verifier ops from program structure")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Applied.