Re: [PATCH bpf-next] bpf: Fix bpf_refcount_acquire's refcount_t address calculation

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Hello:

This patch was applied to bpf/bpf-next.git (master)
by Daniel Borkmann <daniel@xxxxxxxxxxxxx>:

On Fri, 21 Apr 2023 00:44:31 -0700 you wrote:
> When calculating the address of the refcount_t struct within a local
> kptr, bpf_refcount_acquire_impl should add refcount_off bytes to the
> address of the local kptr. Due to some missing parens, the function is
> incorrectly adding sizeof(refcount_t) * refcount_off bytes. This patch
> fixes the calculation.
> 
> Due to the incorrect calculation, bpf_refcount_acquire_impl was trying
> to refcount_inc some memory well past the end of local kptrs, resulting
> in kasan and refcount complaints, as reported in [0]. In that thread,
> Florian and Eduard discovered that bpf selftests written in the new
> style - with __success and an expected __retval, specifically - were not
> actually being run. As a result, selftests added in bpf_refcount series
> weren't really exercising this behavior, and thus didn't unearth the
> bug.
> 
> [...]

Here is the summary with links:
  - [bpf-next] bpf: Fix bpf_refcount_acquire's refcount_t address calculation
    https://git.kernel.org/bpf/bpf-next/c/4ab07209d5cc

You are awesome, thank you!
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