From: "Jonathan Lemon" <jlemon@flugsvamp.com>
To: "John Fastabend" <john.fastabend@gmail.com>
Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, ast@kernel.org,
daniel@iogearbox.net
Subject: Re: [bpf PATCH 9/9] bpf: sockmap/tls, fix pop data with SK_DROP return code
Date: Thu, 09 Jan 2020 15:28:31 -0800 [thread overview]
Message-ID: <62927807-669A-4917-8A88-DCFAC6A31FA5@flugsvamp.com> (raw)
In-Reply-To: <157851818932.1732.14521897338802839226.stgit@ubuntu3-kvm2>
On 8 Jan 2020, at 13:16, John Fastabend wrote:
> When user returns SK_DROP we need to reset the number of copied bytes
> to indicate to the user the bytes were dropped and not sent. If we
> don't reset the copied arg sendmsg will return as if those bytes were
> copied giving the user a positive return value.
>
> This works as expected today except in the case where the user also
> pops bytes. In the pop case the sg.size is reduced but we don't correctly
> account for this when copied bytes is reset. The popped bytes are not
> accounted for and we return a small positive value potentially confusing
> the user.
>
> The reason this happens is due to a typo where we do the wrong comparison
> when accounting for pop bytes. In this fix notice the if/else is not
> needed and that we have a similar problem if we push data except its not
> visible to the user because if delta is larger the sg.size we return a
> negative value so it appears as an error regardless.
>
> Fixes: 7246d8ed4dcce ("bpf: helper to pop data from messages")
> Signed-off-by: John Fastabend <john.fastabend@gmail.com>
> ---
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
prev parent reply other threads:[~2020-01-09 23:28 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-08 21:13 [bpf PATCH 0/9] Fixes for sockmap/tls from more complex BPF progs John Fastabend
2020-01-08 21:14 ` [bpf PATCH 1/9] bpf: sockmap/tls, during free we may call tcp_bpf_unhash() in loop John Fastabend
2020-01-09 1:34 ` Song Liu
2020-01-08 21:14 ` [bpf PATCH 2/9] bpf: sockmap, ensure sock lock held during tear down John Fastabend
2020-01-09 17:10 ` Song Liu
2020-01-08 21:14 ` [bpf PATCH 3/9] bpf: sockmap/tls, push write_space updates through ulp updates John Fastabend
2020-01-09 10:33 ` Jakub Sitnicki
2020-01-09 21:22 ` John Fastabend
2020-01-10 13:40 ` Jakub Sitnicki
2020-01-08 21:14 ` [bpf PATCH 4/9] bpf: sockmap, skmsg helper overestimates push, pull, and pop bounds John Fastabend
2020-01-09 18:37 ` Song Liu
2020-01-08 21:15 ` [bpf PATCH 5/9] bpf: sockmap/tls, msg_push_data may leave end mark in place John Fastabend
2020-01-09 18:51 ` Song Liu
2020-01-08 21:15 ` [bpf PATCH 6/9] bpf: sockmap/tls, tls_sw can create a plaintext buf > encrypt buf John Fastabend
2020-01-09 23:04 ` Jonathan Lemon
2020-01-08 21:15 ` [bpf PATCH 7/9] bpf: sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining John Fastabend
2020-01-09 23:13 ` Jonathan Lemon
2020-01-08 21:16 ` [bpf PATCH 8/9] bpf: sockmap/tls, tls_push_record can not handle zero length skmsg John Fastabend
2020-01-09 20:08 ` Song Liu
2020-01-09 21:25 ` John Fastabend
2020-01-10 23:20 ` John Fastabend
2020-01-08 21:16 ` [bpf PATCH 9/9] bpf: sockmap/tls, fix pop data with SK_DROP return code John Fastabend
2020-01-09 23:28 ` Jonathan Lemon [this message]
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=62927807-669A-4917-8A88-DCFAC6A31FA5@flugsvamp.com \
--to=jlemon@flugsvamp.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=john.fastabend@gmail.com \
--cc=netdev@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).