Re: [PATCH net v3 1/7] net/sched: act_gate: zero-initialize netlink dump struct

[Eric Dumazet]

On Wed, Jan 21, 2026 at 2:39 PM Paul Moses <p@xxxxxxx> wrote:
>
> Yes, it's not proven so you might be right, I knew it was 4 bytes at best. We can do next or toss it, I don't feel strongly either way.
>

These bytes are cleared by C compilers.

https://en.cppreference.com/w/c/language/struct_initialization.html

Only holes might be left uninitialized.

> On Wednesday, January 21st, 2026 at 7:25 AM, Eric Dumazet <edumazet@xxxxxxxxxx> wrote:
>
> >
> >
> > On Wed, Jan 21, 2026 at 2:20 PM Paul Moses p@xxxxxxx wrote:
> >
> > > Zero-initialize the dump struct before selective assignment to avoid
> > > leaking stack padding in netlink replies. This matches other actions
> > > (e.g. act_connmark) that zero-init their dump structs.
> > >
> > > Fixes: a51c328df310 ("net: qos: introduce a gate control flow action")
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Signed-off-by: Paul Moses p@xxxxxxx
> > > ---
> >
> >
> > I do not see a bug to fix, current code is fine.
> >
> > act_connmark problem was that "struct tc_connmark" had a 16bit hole.
> >
> > No such issue for struct tc_gate.