From 860671662d3f7aeec156932aff648e04f0e2ec92 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 10 Sep 2019 10:23:16 +0200 Subject: mnl: fix --echo buffer size again If restart is triggered with --echo, it causes rules to be duplicated which is not correct. Remove restart logic. 1. If user passes --echo, use a default 4mb buffer. 2. assume each element in the batch will result in a 1k notification. This passes tests both in x86_64 and s390. Joint work with Florian Westphal. Fixes: 877baf9538f6 ("src: mnl: retry when we hit -ENOBUFS") Signed-off-by: Pablo Neira Ayuso --- src/mnl.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/src/mnl.c b/src/mnl.c index 9c1f5356..8031bd6a 100644 --- a/src/mnl.c +++ b/src/mnl.c @@ -304,6 +304,8 @@ static ssize_t mnl_nft_socket_sendmsg(struct netlink_ctx *ctx, return sendmsg(mnl_socket_get_fd(ctx->nft->nf_sock), msg, 0); } +#define NFT_MNL_ECHO_RCVBUFF_DEFAULT (MNL_SOCKET_BUFFER_SIZE * 1024) + int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list, uint32_t num_cmds) { @@ -311,8 +313,6 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list, int ret, fd = mnl_socket_get_fd(nl), portid = mnl_socket_get_portid(nl); uint32_t iov_len = nftnl_batch_iovec_len(ctx->batch); char rcv_buf[MNL_SOCKET_BUFFER_SIZE]; - unsigned int enobuf_restarts = 0; - size_t avg_msg_size, batch_size; const struct sockaddr_nl snl = { .nl_family = AF_NETLINK }; @@ -321,17 +321,24 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list, .tv_usec = 0 }; struct iovec iov[iov_len]; - unsigned int scale = 4; struct msghdr msg = {}; + unsigned int rcvbufsiz; + size_t batch_size; fd_set readfds; mnl_set_sndbuffer(ctx->nft->nf_sock, ctx->batch); batch_size = mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len); - avg_msg_size = div_round_up(batch_size, num_cmds); -restart: - mnl_set_rcvbuffer(ctx->nft->nf_sock, num_cmds * avg_msg_size * scale); + if (nft_output_echo(&ctx->nft->output)) { + rcvbufsiz = num_cmds * 1024; + if (rcvbufsiz < NFT_MNL_ECHO_RCVBUFF_DEFAULT) + rcvbufsiz = NFT_MNL_ECHO_RCVBUFF_DEFAULT; + } else { + rcvbufsiz = num_cmds * div_round_up(batch_size, num_cmds) * 4; + } + + mnl_set_rcvbuffer(ctx->nft->nf_sock, rcvbufsiz); ret = mnl_nft_socket_sendmsg(ctx, &msg); if (ret == -1) @@ -350,13 +357,8 @@ restart: break; ret = mnl_socket_recvfrom(nl, rcv_buf, sizeof(rcv_buf)); - if (ret == -1) { - if (errno == ENOBUFS && enobuf_restarts++ < 3) { - scale *= 2; - goto restart; - } + if (ret == -1) return -1; - } ret = mnl_cb_run(rcv_buf, ret, 0, portid, &netlink_echo_callback, ctx); /* Continue on error, make sure we get all acknowledgments */ -- cgit v1.2.3