Re: [GIT PULL] pid: use flex array

From: Linus Torvalds
Date: Thu Jun 29 2023 - 19:53:10 EST


On Wed, 28 Jun 2023 at 03:37, Christian Brauner <brauner@xxxxxxxxxx> wrote:
>
> This contains Kees' work to make struct upid in struct pid a proper
> flexible array and thus gets rid of a bunch of syzbot UBSAN warnings.

Hmm. Of this, about half were replacing "array + index" with "&array[index]".

Honestly, it makes no difference, but the reverse is also true: the
"array + index" is *very* traditional, and if people have problems
with that simple syntax I really don't know what to say. It's kind of
core C. It's *literally* how arrays work, and what the '[]' operator
means.

And of the remaining half, half again is using a truly disgusting

struct_size((struct pid *)0, numbers, X)

thing. That is *GARBAGE*. It's garbage for too many reasons for me to
actually pull this sh*t, but let me just name them:

- 0 isn't a pointer. Stop doing that.

- dammit, we have 'struct_size_t' that does the above disgusting cast
without getting that simple thing wrong.

In other words, this pull request contained half pointless and
unrelated churn, and 25% actual garbage.

In other words, I'm not pulling this to just get the remaining 25%.

Linus