From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] NET: Fix /proc/net/arp for AX.25 Date: Mon, 13 Feb 2017 22:15:51 -0500 (EST) Message-ID: <20170213.221551.904691736246648194.davem@davemloft.net> References: <20170210233857.GA13996@linux-mips.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, thomas@osterried.de, linux-hams@vger.kernel.org To: ralf@linux-mips.org Return-path: In-Reply-To: <20170210233857.GA13996@linux-mips.org> Sender: linux-hams-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Ralf Baechle Date: Sat, 11 Feb 2017 00:38:57 +0100 > When sending ARP requests over AX.25 links the hwaddress in the neighbour > cache are not getting initialized. For such an incomplete arp entry > ax2asc2 will generate an empty string resulting in /proc/net/arp output > like the following: > > $ cat /proc/net/arp > IP address HW type Flags HW address Mask Device > 192.168.122.1 0x1 0x2 52:54:00:00:5d:5f * ens3 > 172.20.1.99 0x3 0x0 * bpq0 > > The missing field will confuse the procfs parsing of arp(8) resulting in > incorrect output for the device such as the following: > > $ arp > Address HWtype HWaddress Flags Mask Iface > gateway ether 52:54:00:00:5d:5f C ens3 > 172.20.1.99 (incomplete) ens3 > > This changes the content of /proc/net/arp to: > > $ cat /proc/net/arp > IP address HW type Flags HW address Mask Device > 172.20.1.99 0x3 0x0 * * bpq0 > 192.168.122.1 0x1 0x2 52:54:00:00:5d:5f * ens3 > > To do so it change ax2asc to put the string "*" in buf for a NULL address > argument. Finally the HW address field is left aligned in a 17 character > field (the length of an ethernet HW address in the usual hex notation) for > readability. > > Signed-off-by: Ralf Baechle Applied, thanks Ralf.