Re: [PATCH v3] exec: load_script: Do not exec truncated interpreter path

From: Linus Torvalds
Date: Fri Feb 15 2019 - 11:06:18 EST


On Fri, Feb 15, 2019 at 7:54 AM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> What's wrong with this simple and fairly self-describing patch?

Simple but with two bugs.

First off, the trivial one: I transposed the arguments to memchr(). It
would need to be

cp = memchr(bprm->buf, '\n', BINPRM_BUF_SIZE);

because I never use memchr().

And even that doesn't really fix it, because what it really wants is
"strnchr()" (to stop at a NUL too). Which doesn't exist.

So skip that patch, it's wrong.

Linus