netdev - What does this code do

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHfguVw9unGL-_ETLzRSVCFqHH5_etafbj1MLaMB+FywLpZjTA@mail.gmail.com>
Date:   Tue, 10 Mar 2020 14:42:11 -0700
From:   Andrej Ras <kermitthekoder@...il.com>
To:     netdev@...r.kernel.org
Subject: What does this code do

While browsing the Linux networking code I came across these two lines
in __ip_append_data() which I do not understand.

                /* Check if the remaining data fits into current packet. */
                copy = mtu - skb->len;
                if (copy < length)
                        copy = maxfraglen - skb->len;
                if (copy <= 0) {

Why not just use maxfraglen.

Perhaps someone can explain why this is needed.

Regards