| Message ID | 49E710E1.3060209@miraclelinux.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Yuta sugiura <ysugiura@miraclelinux.com> Date: Thu, 16 Apr 2009 20:05:05 +0900 > Hi, > I have a suggestion about /proc/net/IPv6_route format. > In rt6_info_route(), interface name is treated as a maximum 8 > characters. > But the type of (struct rt6_inf *)->u.dst.dev->name is char[IFNAMESIZ= > 16] > so, I think that it should change "%8s" to "%16s". Isn't there a way to pass the field length as a paramenter to formatting functions? Then we can just pass in IFNAMESIZE as that parameter. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 16 Apr 2009 04:38:00 -0700 (PDT) David Miller <davem@davemloft.net> wrote: > From: Yuta sugiura <ysugiura@miraclelinux.com> > Date: Thu, 16 Apr 2009 20:05:05 +0900 > > > Hi, > > I have a suggestion about /proc/net/IPv6_route format. > > In rt6_info_route(), interface name is treated as a maximum 8 > > characters. > > But the type of (struct rt6_inf *)->u.dst.dev->name is char[IFNAMESIZ= > > 16] > > so, I think that it should change "%8s" to "%16s". > > Isn't there a way to pass the field length as a paramenter > to formatting functions? Then we can just pass in > IFNAMESIZE as that parameter. seq_printf(m, " %08x %08x %08x %08x %*s\n" rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), rt->u.dst.__use, rt->rt6i_flags, IFNAMESIZE, rt->rt6i_dev ? rt->rt6i_dev->name : "") -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Stephen Hemminger wrote: > On Thu, 16 Apr 2009 04:38:00 -0700 (PDT) > David Miller <davem@davemloft.net> wrote: > >> From: Yuta sugiura <ysugiura@miraclelinux.com> >> Date: Thu, 16 Apr 2009 20:05:05 +0900 >> >>> Hi, >>> I have a suggestion about /proc/net/IPv6_route format. >>> In rt6_info_route(), interface name is treated as a maximum 8 >>> characters. >>> But the type of (struct rt6_inf *)->u.dst.dev->name is char[IFNAMESIZ= >>> 16] >>> so, I think that it should change "%8s" to "%16s". >> Isn't there a way to pass the field length as a paramenter >> to formatting functions? Then we can just pass in >> IFNAMESIZE as that parameter. > > seq_printf(m, " %08x %08x %08x %08x %*s\n" > rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), > rt->u.dst.__use, rt->rt6i_flags, > IFNAMESIZE, > rt->rt6i_dev ? rt->rt6i_dev->name : "") Does the kernel actually truncate an interface name more than 8 chars long in the original version? I did a quick test in userspace and found that printf("%*s\n", 1, "foo"); prints: foo I think the width specifier is used for *minimum* width, not maximum. -Brian -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Stephen Hemminger <shemminger@vyatta.com> writes: > On Thu, 16 Apr 2009 04:38:00 -0700 (PDT) > David Miller <davem@davemloft.net> wrote: > >> From: Yuta sugiura <ysugiura@miraclelinux.com> >> Date: Thu, 16 Apr 2009 20:05:05 +0900 >> >> > Hi, >> > I have a suggestion about /proc/net/IPv6_route format. >> > In rt6_info_route(), interface name is treated as a maximum 8 >> > characters. >> > But the type of (struct rt6_inf *)->u.dst.dev->name is char[IFNAMESIZ= >> > 16] >> > so, I think that it should change "%8s" to "%16s". >> >> Isn't there a way to pass the field length as a paramenter >> to formatting functions? Then we can just pass in >> IFNAMESIZE as that parameter. > > seq_printf(m, " %08x %08x %08x %08x %*s\n" > rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), > rt->u.dst.__use, rt->rt6i_flags, > IFNAMESIZE, > rt->rt6i_dev ? rt->rt6i_dev->name : "") Actually since it is the last item on the line a field width does not make much sense, and omitting it would print the name left justified. (And RT6_INFO_LEN is not used any more.) Andreas.
On Thu, 16 Apr 2009 18:47:04 +0200 Andreas Schwab <schwab@linux-m68k.org> wrote: > Stephen Hemminger <shemminger@vyatta.com> writes: > > > On Thu, 16 Apr 2009 04:38:00 -0700 (PDT) > > David Miller <davem@davemloft.net> wrote: > > > >> From: Yuta sugiura <ysugiura@miraclelinux.com> > >> Date: Thu, 16 Apr 2009 20:05:05 +0900 > >> > >> > Hi, > >> > I have a suggestion about /proc/net/IPv6_route format. > >> > In rt6_info_route(), interface name is treated as a maximum 8 > >> > characters. > >> > But the type of (struct rt6_inf *)->u.dst.dev->name is char[IFNAMESIZ= > >> > 16] > >> > so, I think that it should change "%8s" to "%16s". > >> > >> Isn't there a way to pass the field length as a paramenter > >> to formatting functions? Then we can just pass in > >> IFNAMESIZE as that parameter. > > > > seq_printf(m, " %08x %08x %08x %08x %*s\n" > > rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), > > rt->u.dst.__use, rt->rt6i_flags, > > IFNAMESIZE, > > rt->rt6i_dev ? rt->rt6i_dev->name : "") > > Actually since it is the last item on the line a field width does not > make much sense, and omitting it would print the name left justified. > > (And RT6_INFO_LEN is not used any more.) > > Andreas. > The issue is what happens if name is not null terminated. in this case I bet the kernel already handles that. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Stephen Hemminger <shemminger@vyatta.com> writes:
> The issue is what happens if name is not null terminated.
That cannot happen. And a field width would not help anyway.
Andreas.
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 1394ddb..9ad58e7 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2434,7 +2434,7 @@ static int ip6_route_dev_notify(struct notifier_block *this, #ifdef CONFIG_PROC_FS -#define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1) +#define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 48 + 5 + 1) struct rt6_proc_arg { @@ -2462,7 +2462,7 @@ static int rt6_info_route(struct rt6_info *rt, void *p_arg) } else { seq_puts(m, "00000000000000000000000000000000"); } - seq_printf(m, " %08x %08x %08x %08x %8s\n", + seq_printf(m, " %08x %08x %08x %08x %16s\n", rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), rt->u.dst.__use, rt->rt6i_flags, rt->rt6i_dev ? rt->rt6i_dev->name : "");