On Fri, May 31, 2019 at 02:11:41PM -0400, Eric Garver wrote: > On Thu, May 30, 2019 at 12:55:27PM +0200, Pablo Neira Ayuso wrote: > > Set a receiver buffer size based on the number of commands and the > > average message size, this is useful for the --echo option in order to > > avoid ENOBUFS errors. > > > > Double the estimated size is used to ensure enough receiver buffer > > space. > > > > Skip buffer receiver logic if estimation is smaller than current buffer. > > > > Reported-by: Phil Sutter <[email protected]> > > Signed-off-by: Pablo Neira Ayuso <[email protected]> > > --- > [..] > > diff --git a/src/libnftables.c b/src/libnftables.c > > index 199dbc97b801..a58b8ca9dcf6 100644 > > --- a/src/libnftables.c > > +++ b/src/libnftables.c > [..] > > @@ -308,14 +310,17 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct > > list_head *err_list) > > .tv_sec = 0, > > .tv_usec = 0 > > }; > > - fd_set readfds; > > struct iovec iov[iov_len]; > > struct msghdr msg = {}; > > + fd_set readfds; > > int err = 0; > > > > mnl_set_sndbuffer(ctx->nft->nf_sock, ctx->batch); > > > > - mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len); > > + batch_size = mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len); > > + avg_msg_size = div_round_up(batch_size, num_cmds); > > + > > + mnl_set_rcvbuffer(ctx->nft->nf_sock, num_cmds * avg_msg_size * 2); > > I think this calculation is incorrect.
Yes, see v4 of this patch: https://patchwork.ozlabs.org/patch/1107737/ > I'm still getting ENOBUFS with Phil's testcase and firewalld's > testsuite (large json blob). I changed the multiplier from 2 to 6 > and it worked. I just pushed out the patchset, the last version is using a multiplier of 4, I modified Phil's testcase to 100000 and it works fine. Please try the version upstream and let me know. We can enhance this code by checking for ENOBUFS in _sendmsg(), extend the buffer size and retry. Then, we also need to update kernel code to abort the transaction in case NLM_F_ECHO flag is set on and we hit ENOBUFS.
