On Mon, Oct 19, 2020 at 11:33:56AM +0200, Roberto Bergantinos Corpas wrote:
> Its possible that using AUTH_SYS and mountd manage-gids option a
> user may hit the 8k RPC channel buffer limit. This have been observed
> on field, causing unanswered RPCs on clients after mountd fails to
> write on channel :
>
> rpc.mountd[11231]: auth_unix_gid: error writing reply
>
> Userland nfs-utils uses a buffer size of 32k (RPC_CHAN_BUF_SIZE), so
> lets match those two.
Thanks, applying.
That should allow about 4000 group memberships. If that doesn't do it
then maybe it's time to rethink....
--b.
>
> Signed-off-by: Roberto Bergantinos Corpas <rbergant@xxxxxxxxxx>
> ---
> net/sunrpc/cache.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
> index baef5ee43dbb..08df4c599ab3 100644
> --- a/net/sunrpc/cache.c
> +++ b/net/sunrpc/cache.c
> @@ -908,7 +908,7 @@ static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
> static ssize_t cache_slow_downcall(const char __user *buf,
> size_t count, struct cache_detail *cd)
> {
> - static char write_buf[8192]; /* protected by queue_io_mutex */
> + static char write_buf[32768]; /* protected by queue_io_mutex */
> ssize_t ret = -EINVAL;
>
> if (count >= sizeof(write_buf))
> --
> 2.21.0
