BPF List
 help / color / mirror / Atom feed
From: John Fastabend <john.fastabend@gmail.com>
To: Jakub Sitnicki <jakub@cloudflare.com>,  bpf@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>,
	 Daniel Borkmann <daniel@iogearbox.net>,
	 John Fastabend <john.fastabend@gmail.com>,
	 Hillf Danton <hdanton@sina.com>,
	 Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
	 kernel-team@cloudflare.com,
	 syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com
Subject: RE: [PATCH bpf 0/3] Block deletes from sockmap for tracing programs
Date: Mon, 27 May 2024 09:46:37 -0700	[thread overview]
Message-ID: <6654b8ede640b_1c7620871@john.notmuch> (raw)
In-Reply-To: <20240527-sockmap-verify-deletes-v1-0-944b372f2101@cloudflare.com>

Jakub Sitnicki wrote:
> We have seen a few syzkaller reports of locking violations triggered by
> map_delete from sockmap/sockhash from an unexpected code path, for instance
> when irqs were disabled, or during a kfree inside a map_update.
> 
> The consensus is [1] to block map_delete op in the verifier for programs
> which are not allowed to update sockmap/sockhash already today, instead of
> trying to make sockmap deletes lock-safe in every possible context.

+1 thanks Jakub. This makes sense to me I've never found a use case for
deleting socks from a tracing program.

  parent reply	other threads:[~2024-05-27 16:46 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-27 11:20 [PATCH bpf 0/3] Block deletes from sockmap for tracing programs Jakub Sitnicki
2024-05-27 11:20 ` [PATCH bpf 1/3] bpf: Allow delete from sockmap/sockhash only if update is allowed Jakub Sitnicki
2024-05-27 16:49   ` John Fastabend
2024-05-27 11:20 ` [PATCH bpf 2/3] Revert "bpf, sockmap: Prevent lock inversion deadlock in map delete elem" Jakub Sitnicki
2024-05-27 16:50   ` John Fastabend
2024-05-27 11:20 ` [PATCH bpf 3/3] selftests/bpf: Cover verifier checks for mutating sockmap/sockhash Jakub Sitnicki
2024-05-27 16:52   ` John Fastabend
2024-05-27 16:46 ` John Fastabend [this message]
2024-05-27 17:40 ` [PATCH bpf 0/3] Block deletes from sockmap for tracing programs patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6654b8ede640b_1c7620871@john.notmuch \
    --to=john.fastabend@gmail.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=hdanton@sina.com \
    --cc=jakub@cloudflare.com \
    --cc=kernel-team@cloudflare.com \
    --cc=penguin-kernel@i-love.sakura.ne.jp \
    --cc=syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox