Re: [PATCH bpf-next] bpf: sock recvbuff must be limited by rmem_max in bpf_setsockopt()

[Lawrence Brakmo]

On 1/22/19, 9:42 AM, "Martin Lau" <ka...@fb.com> wrote:

    On Sat, Jan 19, 2019 at 02:20:30PM +0800, Yafang Shao wrote:
    > When sock recvbuff is set by bpf_setsockopt(), the value must by limited
    > by rmem_max.
    > It is the same with sendbuff.
    > 
    > Signed-off-by: Yafang Shao <laoar.s...@gmail.com>
    For bug fixes, please target the bpf branch instead of bpf-next
    and please also add the Fixes tag:
    Fixes: 8c4b4c7e9ff0 ("bpf: Add setsockopt helper function to bpf")
    
    Patch LGTM,
    Acked-by: Martin KaFai Lau <ka...@fb.com>
    
    Cc: Lawrence Brakmo, thought?

Yafang, thank you for the fix, LGTM.
Acked-by: Lawrence Brakmo <bra...@fb.com>
    
    > ---
    >  net/core/filter.c | 2 ++
    >  1 file changed, 2 insertions(+)
    > 
    > diff --git a/net/core/filter.c b/net/core/filter.c
    > index 447dd1b..f30b58a 100644
    > --- a/net/core/filter.c
    > +++ b/net/core/filter.c
    > @@ -4111,10 +4111,12 @@ static unsigned long bpf_xdp_copy(void *dst_buff, 
const void *src_buff,
    >           /* Only some socketops are supported */
    >           switch (optname) {
    >           case SO_RCVBUF:
    > +                 val = min_t(u32, val, sysctl_rmem_max);
    >                   sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
    >                   sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
    >                   break;
    >           case SO_SNDBUF:
    > +                 val = min_t(u32, val, sysctl_wmem_max);
    >                   sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
    >                   sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
    >                   break;
    > -- 
    > 1.8.3.1
    >