linux-kernel - Odd use of %14pM in net/batman-adv/distributed-arp-table.c

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Date:   Tue, 13 Jun 2017 14:51:41 -0700
From:   Joe Perches <joe@...ches.com>
To:     Marek Lindner <mareklindner@...mailbox.ch>,
        Simon Wunderlich <sw@...onwunderlich.de>,
        Antonio Quartulli <a@...table.cc>
Cc:     "David S. Miller" <davem@...emloft.net>,
        b.a.t.m.a.n@...ts.open-mesh.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Odd use of %14pM in net/batman-adv/distributed-arp-table.c

An output mac address is 17 bytes

         1
12345678901234567
00:11:22:33:44:55

but in net/batman-adv/distributed-arp-table.c

int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset)
{
[...]
			seq_printf(seq, " * %15pI4 %14pM %4i %6i:%02i\n",
				   &dat_entry->ip, dat_entry->mac_addr,
				   batadv_print_vid(dat_entry->vid),
				   last_seen_mins, last_seen_secs);

%14pM is odd as this should not emit the last byte of the
mac address.  So given the example above, it would output
00:11:22:33:44

Is that what's really desired?

If so, I'd suggest using something more obvious like %5phC