Re: [PATCH v6 bpf-next 1/4] bpf: properly verify tail call behavior

patchwork-bot+netdevbpf
2025-11-22T02:00:47Z

Hello:

This series was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <ast@kernel.org>:

On Wed, 19 Nov 2025 17:03:52 +0100 you wrote:
> A successful ebpf tail call does not return to the caller, but to the
> caller-of-the-caller, often just finishing the ebpf program altogether.
>
> Any restrictions that the verifier needs to take into account - notably
> the fact that the tail call might have modified packet pointers - are to
> be checked on the caller-of-the-caller. Checking it on the caller made
> the verifier refuse perfectly fine programs that would use the packet
> pointers after a tail call, which is no problem as this code is only
> executed if the tail call was unsuccessful, i.e. nothing happened.
>
> [...]

Here is the summary with links:
- [v6,bpf-next,1/4] bpf: properly verify tail call behavior
https://git.kernel.org/bpf/bpf-next/c/e3245f899043
- [v6,bpf-next,2/4] bpf: test the proper verification of tail calls
https://git.kernel.org/bpf/bpf-next/c/978da762ea45
- [v6,bpf-next,3/4] bpf: correct stack liveness for tail calls
https://git.kernel.org/bpf/bpf-next/c/e40f5a6bf88a
- [v6,bpf-next,4/4] bpf: test the correct stack liveness of tail calls
https://git.kernel.org/bpf/bpf-next/c/8f7cf305a15e

You are awesome, thank you!
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