linux-kernel - Re: [PATCH bpf-next 0/3] Don't invoke KPTR

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sun, 26 Mar 2023 00:12:15 +0000
From:   patchwork-bot+netdevbpf@...nel.org
To:     David Vernet <void@...ifault.com>
Cc:     bpf@...r.kernel.org, ast@...nel.org, daniel@...earbox.net,
        andrii@...nel.org, martin.lau@...ux.dev, song@...nel.org,
        yhs@...com, john.fastabend@...il.com, kpsingh@...nel.org,
        sdf@...gle.com, haoluo@...gle.com, jolsa@...nel.org,
        linux-kernel@...r.kernel.org, kernel-team@...a.com
Subject: Re: [PATCH bpf-next 0/3] Don't invoke KPTR_REF destructor on NULL xchg

Hello:

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

On Sat, 25 Mar 2023 16:31:41 -0500 you wrote:
> When a map value is being freed, we loop over all of the fields of the
> corresponding BPF object and issue the appropriate cleanup calls
> corresponding to the field's type. If the field is a referenced kptr, we
> atomically xchg the value out of the map, and invoke the kptr's
> destructor on whatever was there before.
> 
> Currently, we always invoke the destructor (or bpf_obj_drop() for a
> local kptr) on any kptr, including if no value was xchg'd out of the
> map. This means that any function serving as the kptr's KF_RELEASE
> destructor must always treat the argument as possibly NULL, and we
> invoke unnecessary (and seemingly unsafe) cleanup logic for the local
> kptr path as well.
> 
> [...]

Here is the summary with links:
  - [bpf-next,1/3] bpf: Only invoke kptr dtor following non-NULL xchg
    https://git.kernel.org/bpf/bpf-next/c/1431d0b584a6
  - [bpf-next,2/3] bpf: Remove now-unnecessary NULL checks for KF_RELEASE kfuncs
    https://git.kernel.org/bpf/bpf-next/c/fb2211a57c11
  - [bpf-next,3/3] bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS
    https://git.kernel.org/bpf/bpf-next/c/6c831c468412

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html