-----Eric Dumazet <eric.duma...@gmail.com> wrote: ----- >To: Evgeny Cherkashin/Russia/IBM@IBMRU >From: Eric Dumazet <eric.duma...@gmail.com> >Date: 2016-05-04 16:13 >Cc: cros...@average.org, netdev@vger.kernel.org >Subject: Re: [PATCH net] igmp: fix byte order in /proc/net/igmp >output > >On Wed, 2016-05-04 at 14:11 +0200, Eugene Crosser wrote: >> /proc/net/igmp is a readonly attribute that shows multicast groups >> to which different network interfaces are subscribed. Among other >> things, it displays `multiaddr` which is a 32 bit >network-byte-order >> field, in hexadecimal format. Prior to this patch, the field was >> displayed as an integer, resulting in reverse byte order on little >> endian architectures. This patch converts it with ntohl() for >display >> the same way as this is done for the /proc/net/mcfilter attribute. >> >> The patch changes (corrects) user-visible behaviour. >> >> Signed-off-by: Eugene Crosser <eugene.cros...@ru.ibm.com> >> --- >> net/ipv4/igmp.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c >> index b3086cf..f9d2139 100644 >> --- a/net/ipv4/igmp.c >> +++ b/net/ipv4/igmp.c >> @@ -2722,7 +2722,7 @@ static int igmp_mc_seq_show(struct seq_file >*seq, void *v) >> delta = im->timer.expires - jiffies; >> seq_printf(seq, >> "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", >> - im->multiaddr, im->users, >> + ntohl(im->multiaddr), im->users, >> im->tm_running, >> im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, >> im->reporter); > > >I do not believe we can change this. This is unfortunately too late. > >/proc/net/tcp has the same 'issue' or if you prefer, well known >behavior. > >Such change would break basically all /proc/net/igmp users.
I understand that. It is unfortunate though that the byte order is not _just_ wrong, it's _different_ on BE and LE machines... Oh well. Thanks, Eugene
