On 10 Feb 2023, at 10:19, Alexander V. Chernikov wrote:
> The branch stable/13 has been updated by melifaro:
>
> URL:
> https://cgit.FreeBSD.org/src/commit/?id=c3d3f3594fdf653392936594b75ec330af12d7fa
>
> commit c3d3f3594fdf653392936594b75ec330af12d7fa
> Author: Alexander V. Chernikov <[email protected]>
> AuthorDate: 2023-02-10 16:07:17 +0000
> Commit: Alexander V. Chernikov <[email protected]>
> CommitDate: 2023-02-10 16:07:22 +0000
>
> netlink: allow to override sb_max for netlink sockets.
>
> Netlink sockets sometimes require larger buffers than other sockets.
> For example, full-view IPv4 dump sent via netlink may consume 50+
> megabytes.
> The desired buffer may be bigger than the system maximum `sb_max`.
> FreeBSD HEAD has a mechanism for overriding protocol `setsockopt()`
> handler,
> which netlink uses to permit buffer reservations beyond `sb_max`.
> This behaviour is handy as it doesn't require system administrator to
> lift
> the limits for other sockets.
> Stable/13 lack such muchanism, so a different approach has to be used.
> This diff is a direct commit to stable/13 and it simply copies the logic
> from
> Netlink in -HEAD for checking if the larger buffer size should be
> permitted.
>
> Differential Revision: https://reviews.freebsd.org/D38472
> ---
> sys/kern/uipc_sockbuf.c | 3 ++-
> sys/kern/uipc_socket.c | 10 ++++++++++
> sys/sys/sockopt.h | 1 +
> 3 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/sys/kern/uipc_sockbuf.c b/sys/kern/uipc_sockbuf.c
> index cbfcc0e5fe95..277965412779 100644
> --- a/sys/kern/uipc_sockbuf.c
> +++ b/sys/kern/uipc_sockbuf.c
> @@ -693,7 +693,8 @@ sbsetopt(struct socket *so, int cmd, u_long cc)
> if (*lowat > *hiwat)
> *lowat = *hiwat;
> } else {
> - if (!sbreserve_locked(sb, cc, so, curthread))
> + u_long limit = sogetmaxbuf(so);
Spaces instead of tabs.
Mike
> + if (!sbreserve_locked_limit(sb, cc, so, limit,
> curthread))
> error = ENOBUFS;
> }
> if (error == 0)
> diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
> index f8931b653a4d..fdf718de2483 100644
> --- a/sys/kern/uipc_socket.c
> +++ b/sys/kern/uipc_socket.c
> @@ -128,6 +128,7 @@ __FBSDID("$FreeBSD$");
> #include <sys/event.h>
> #include <sys/eventhandler.h>
> #include <sys/poll.h>
> +#include <sys/priv.h>
> #include <sys/proc.h>
> #include <sys/protosw.h>
> #include <sys/sbuf.h>
> @@ -2975,6 +2976,15 @@ sooptcopyin(struct sockopt *sopt, void *buf, size_t
> len, size_t minlen)
> return (0);
> }
>
> +u_long
> +sogetmaxbuf(struct socket *so)
> +{
> + if (so->so_proto->pr_domain->dom_family != PF_NETLINK)
> + return (sb_max);
> + u_long nl_maxsockbuf = 512 * 1024 * 1024; /* 512M, XXX: init based on
> physmem */
> + return ((priv_check(curthread, PRIV_NET_ROUTE) == 0) ? nl_maxsockbuf :
> sb_max);
> +}
> +
> /*
> * Kernel version of setsockopt(2).
> *
> diff --git a/sys/sys/sockopt.h b/sys/sys/sockopt.h
> index cb7fc3ffca27..d01d62f21680 100644
> --- a/sys/sys/sockopt.h
> +++ b/sys/sys/sockopt.h
> @@ -68,5 +68,6 @@ int accept_filt_getopt(struct socket *, struct sockopt *);
> int accept_filt_setopt(struct socket *, struct sockopt *);
> int so_setsockopt(struct socket *so, int level, int optname,
> void *optval, size_t optlen);
> +u_long sogetmaxbuf(struct socket *so);
>
> #endif /* _SYS_SOCKOPT_H_ */
