mnl: larger receive socket buffer for netlink errors

Assume each error in the batch will result in a 1k notification for the
non-echo flag set on case as described in 860671662d3f ("mnl: fix --echo
buffer size again").

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/src/mnl.c b/src/mnl.c
index ca4f4b2acda9108fe59724c71960bde0723f60fe..6699b917c450eca12f395043810c1f114b6e74c8 100644 (file)
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -273,24 +273,16 @@ static int mnl_set_rcvbuffer(const struct mnl_socket *nl, socklen_t bufsiz)
        return ret;
 }
 
-static size_t mnl_nft_batch_to_msg(struct netlink_ctx *ctx, struct msghdr *msg,
-                                  const struct sockaddr_nl *snl,
-                                  struct iovec *iov, unsigned int iov_len)
+static void mnl_nft_batch_to_msg(struct netlink_ctx *ctx, struct msghdr *msg,
+                                const struct sockaddr_nl *snl,
+                                struct iovec *iov, unsigned int iov_len)
 {
-       unsigned int i;
-       size_t len = 0;
-
        msg->msg_name           = (struct sockaddr_nl *)snl;
        msg->msg_namelen        = sizeof(*snl);
        msg->msg_iov            = iov;
        msg->msg_iovlen         = iov_len;
 
        nftnl_batch_iovec(ctx->batch, iov, iov_len);
-
-       for (i = 0; i < iov_len; i++)
-               len += msg->msg_iov[i].iov_len;
-
-       return len;
 }
 
 static ssize_t mnl_nft_socket_sendmsg(struct netlink_ctx *ctx,
@@ -385,7 +377,6 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list,
        struct iovec iov[iov_len];
        struct msghdr msg = {};
        unsigned int rcvbufsiz;
-       size_t batch_size;
        fd_set readfds;
        static mnl_cb_t cb_ctl_array[NLMSG_MIN_TYPE] = {
                [NLMSG_ERROR] = mnl_batch_extack_cb,
@@ -397,14 +388,12 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list,
 
        mnl_set_sndbuffer(ctx->nft->nf_sock, ctx->batch);
 
-       batch_size = mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len);
+       mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len);
 
+       rcvbufsiz = num_cmds * 1024;
        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);