net: ipv4: fragmentation: Drop the packet if fragmentation fails (41431637) · Commits · Wenxi XU / zephyr

If we could not fragment the IPv4 packet, then drop it and do not try to send it. Let the upper layer re-send the packet if needed. It is causing more trouble if we try to send the packet and not honor the MTU setting. Fixes #81021 Signed-off-by:

Jukka Rissanen <jukka.rissanen@nordicsemi.no>

subsys/net/ip/ipv4_fragment.c

+5 −6

Original line number	Diff line number	Diff line
		@@ -635,17 +635,16 @@ enum net_verdict net_ipv4_prepare_for_send(struct net_pkt *pkt)
		if (ret < 0) {
		LOG_DBG("Cannot fragment IPv4 pkt (%d)", ret);

		if (ret == -ENOMEM \|\| ret == -ENOBUFS \|\| ret == -EPERM) {
		/* Try to send the packet if we could not allocate enough
		* network packets or if the don't fragment flag is set
		if (ret == -EPERM) {
		/* Try to send the packet if the don't fragment flag is set
		* and hope the original large packet can be sent OK.
		*/
		goto ignore_frag_error;
		} else {
		}

		/* Other error, drop the packet */
		return NET_DROP;
		}
		}

		/* We need to unref here because we simulate the packet being sent. */
		net_pkt_unref(pkt);

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