public inbox for dash@vger.kernel.org
 help / color / mirror / Atom feed
From: Herbert Xu <herbert@gondor.apana.org.au>
To: Tiago de Paula <tiagodepalves@gmail.com>
Cc: dash@vger.kernel.org, tiagodepalves@gmail.com
Subject: Re: [PATCH] input: Fix heap-buffer-overflow in preadbuffer on long lines
Date: Sat, 14 Mar 2026 18:23:37 +0900	[thread overview]
Message-ID: <abUpGUbMsSSM8mEF@gondor.apana.org.au> (raw)
In-Reply-To: <CAO_NRt5mv7E-qkSA2hE+4HsQMzpczrF9ZAWL-jKbW0Li1F3U0A@mail.gmail.com>

Tiago de Paula <tiagodepalves@gmail.com> wrote:
> Update lleft before calling preadfd so buffered data is preserved
> when refilling the buffer during long line scanning, preventing
> out-of-bounds reads.
> 
> Fixes: a065467315dc ("input: Move newline loop into preadbuffer")
> Signed-off-by: Tiago de Paula <tiagodepalves@gmail.com>
> ---
> I discovered this via perlbrew: config.sh contained a single
> 'cppsymbols=...' line that was 12502 characters long. The issue
> can be replicated with:
> 
>    python -c 'print("VAR=" + "a"*8300)' > repro.sh
>    dash repro.sh
> 
> AddressSanitizer reports a heap-buffer-overflow in preadbuffer(),
> which led to me this fix.
> 
> src/input.c | 1 +
> 1 file changed, 1 insertion(+)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

      reply	other threads:[~2026-03-14  9:23 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-12  7:29 [PATCH] input: Fix heap-buffer-overflow in preadbuffer on long lines Tiago de Paula
2026-03-14  9:23 ` Herbert Xu [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=abUpGUbMsSSM8mEF@gondor.apana.org.au \
    --to=herbert@gondor.apana.org.au \
    --cc=dash@vger.kernel.org \
    --cc=tiagodepalves@gmail.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