On Tue, Mar 29, 2022 at 03:02:56PM -0700, Tadeusz Struk wrote:
> Please apply this to stable 5.10.y, and 5.15.y
> ---8<---
>
> From: Kees Cook <keescook@xxxxxxxxxxxx>
>
> Upstream commit: 1a2fb220edca ("skbuff: Extract list pointers to silence compiler warnings")
>
> Under both -Warray-bounds and the object_size sanitizer, the compiler is
> upset about accessing prev/next of sk_buff when the object it thinks it
> is coming from is sk_buff_head. The warning is a false positive due to
> the compiler taking a conservative approach, opting to warn at casting
> time rather than access time.
>
> However, in support of enabling -Warray-bounds globally (which has
> found many real bugs), arrange things for sk_buff so that the compiler
> can unambiguously see that there is no intention to access anything
> except prev/next. Introduce and cast to a separate struct sk_buff_list,
> which contains _only_ the first two fields, silencing the warnings:
We don't have -Warray-bounds enabled on any stable kernel tree, so why
is this needed?
Where is this showing up as a problem?
thanks,
greg k-h
