Re: [PATCH bpf] libbpf: fix passing uninitialized bytes to setsockopt

From: Alexei Starovoitov
Date: Sun Oct 13 2019 - 00:59:55 EST

On Sat, Oct 12, 2019 at 9:52 PM Ilya Maximets <i.maximets@xxxxxxx> wrote:
> 'struct xdp_umem_reg' has 4 bytes of padding at the end that makes
> valgrind complain about passing uninitialized stack memory to the
> syscall:
> Syscall param socketcall.setsockopt() points to uninitialised byte(s)
> at 0x4E7AB7E: setsockopt (in /usr/lib64/
> by 0x4BDE035: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:172)
> Uninitialised value was created by a stack allocation
> at 0x4BDDEBA: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:140)
> Padding bytes appeared after introducing of a new 'flags' field.
> Fixes: 10d30e301732 ("libbpf: add flags to umem config")
> Signed-off-by: Ilya Maximets <i.maximets@xxxxxxx>

Something is not right with (e|g)mail.
This is 3rd email I got with the same patch.
First one (the one that was applied) was 3 days ago.