Hi, On Tue, Apr 9, 2024 at 9:07 AM Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote: > > > On 4/9/24 14:15, Edward Adam Davis wrote: > > The optlen value passed by syzbot to _sys_setsockopt() is 2, which results in > > only 2 bytes being allocated when allocating memory to kernel_optval, and the > > optval size passed when calling the function copy_from_sockptr() is 4 bytes. > > Here, optlen is determined uniformly in the entry function __sys_setsockopt(). > > If its value is less than 4, the parameter is considered invalid. > > > > Reported-by: syzbot+837ba09d9db969068367@xxxxxxxxxxxxxxxxxxxxxxxxx > > Reported-by: syzbot+b71011ec0a23f4d15625@xxxxxxxxxxxxxxxxxxxxxxxxx > > Reported-by: syzbot+d4ecae01a53fd9b42e7d@xxxxxxxxxxxxxxxxxxxxxxxxx > > Signed-off-by: Edward Adam Davis <eadavis@xxxxxx> > > > I think I gave my feedback already. > > Please do not ignore maintainers feedback. > > This patch is absolutely wrong. > > Some setsockopt() deal with optlen == 1 just fine, thank you very much. +1, I don't think the setsockopt interface has a fixed minimum of sizeof(int), so this is a nak from me as well. -- Luiz Augusto von Dentz