Hello,
On Sat, 6 Oct 2012, Arnd Bergmann wrote:
> On Friday 05 October 2012, Julian Anastasov wrote:
> >
> > Hello,
> >
> > On Fri, 5 Oct 2012, Arnd Bergmann wrote:
> >
> > > The ip_vs_set_timeout function sets timeouts for TCP and UDP, which
> > > can be enabled independently at compile time. The debug message
> > > always prints both timeouts that are passed into the function,
> > > but if one is disabled, the message will show uninitialized data.
> > >
> > > This splits the debug message into two separte IP_VS_DBG statements
> > > that are in the same #ifdef section to ensure we only print the
> > > text about what is actually going on.
> > >
> > > Without this patch, building ARM ixp4xx_defconfig results in:
> >
> > Are there any CONFIG_IP_VS_PROTO_xxx options in this
> > default config? It is a waste of memory if IPVS is compiled
> > without any protocols.
>
> They all appear to be turned off:
>
> $ grep CONFIG_IP_VS obj-tmp/.config
> CONFIG_IP_VS=m
> CONFIG_IP_VS_DEBUG=y
> CONFIG_IP_VS_TAB_BITS=12
> # CONFIG_IP_VS_PROTO_TCP is not set
> # CONFIG_IP_VS_PROTO_UDP is not set
> # CONFIG_IP_VS_PROTO_AH_ESP is not set
> # CONFIG_IP_VS_PROTO_ESP is not set
> # CONFIG_IP_VS_PROTO_AH is not set
> # CONFIG_IP_VS_PROTO_SCTP is not set
> CONFIG_IP_VS_RR=m
> CONFIG_IP_VS_WRR=m
> CONFIG_IP_VS_LC=m
> CONFIG_IP_VS_WLC=m
> CONFIG_IP_VS_LBLC=m
> CONFIG_IP_VS_LBLCR=m
> CONFIG_IP_VS_DH=m
> CONFIG_IP_VS_SH=m
> # CONFIG_IP_VS_SED is not set
> # CONFIG_IP_VS_NQ is not set
> CONFIG_IP_VS_SH_TAB_BITS=8
Something should be changed here, may be at least
TCP/UDP, who knows.
> > > net/netfilter/ipvs/ip_vs_ctl.c: In function 'ip_vs_genl_set_cmd':
> > > net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.udp_timeout' may be
> > > used uninitialized in this function [-Wuninitialized]
> > > net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.udp_timeout' was
> > > declared here
> > > net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.tcp_fin_timeout' may
> > > be used uninitialized in this function [-Wuninitialized]
> > > net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.tcp_fin_timeout' was
> > > declared here
> > > net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.tcp_timeout' may be
> > > used uninitialized in this function [-Wuninitialized]
> > > net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.tcp_timeout' was
> > > declared here
> >
> > There are many __ip_vs_get_timeouts callers but
> > just one calls memset(&t, 0, sizeof(t)) before that,
> > problem only for ip_vs_genl_set_config and ip_vs_set_timeout.
> >
> > To be safe, can we move this memset into
> > __ip_vs_get_timeouts instead of playing games with defines?:
> >
> > memset(t, 0, sizeof(*t));
> >
> > This debug message will be more precise in showing the
> > changed values if we replace the __ip_vs_get_timeouts
> > call in ip_vs_genl_set_config with memset(&t, 0, sizeof(t)).
> > Then we will see 0 for values that are not changed/supported.
>
> 8<-----
> ipvs: initialize returned data in do_ip_vs_get_ctl
>
> As reported by a gcc warning, the do_ip_vs_get_ctl does not initalize
> all the members of the ip_vs_timeout_user structure it returns if
> at least one of the TCP or UDP protocols is disabled for ipvs.
>
> This makes sure that the data is always initialized, before it is
> returned as a response to IPVS_CMD_GET_CONFIG or printed as a
> debug message in IPVS_CMD_SET_CONFIG.
>
> Without this patch, building ARM ixp4xx_defconfig results in:
>
> net/netfilter/ipvs/ip_vs_ctl.c: In function 'ip_vs_genl_set_cmd':
> net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.udp_timeout' may be used
> uninitialized in this function [-Wuninitialized]
> net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.udp_timeout' was declared
> here
> net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.tcp_fin_timeout' may be
> used uninitialized in this function [-Wuninitialized]
> net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.tcp_fin_timeout' was
> declared here
> net/netfilter/ipvs/ip_vs_ctl.c:2238:47: warning: 't.tcp_timeout' may be used
> uninitialized in this function [-Wuninitialized]
> net/netfilter/ipvs/ip_vs_ctl.c:3322:28: note: 't.tcp_timeout' was declared
> here
>
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
>
> diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
> index 2770f85..3995d2e 100644
> --- a/net/netfilter/ipvs/ip_vs_ctl.c
> +++ b/net/netfilter/ipvs/ip_vs_ctl.c
> @@ -2590,6 +2588,7 @@ __ip_vs_get_timeouts(struct net *net, struct
> ip_vs_timeout_user *u)
> #if defined(CONFIG_IP_VS_PROTO_TCP) || defined(CONFIG_IP_VS_PROTO_UDP)
> struct ip_vs_proto_data *pd;
> #endif
That is what we want. If you plan another submission
you can add empty line before this memset and to replace
the __ip_vs_get_timeouts call in ip_vs_genl_set_config with
memset but they are cosmetic changes. Or may be Simon will
take care about the coding style when applying the change.
Acked-by: Julian Anastasov <j...@ssi.bg>
> + memset(u, 0, sizeof (*u));
>
> #ifdef CONFIG_IP_VS_PROTO_TCP
> pd = ip_vs_proto_data_get(net, IPPROTO_TCP);
> @@ -2768,7 +2767,6 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user
> *user, int *len)
> {
> struct ip_vs_timeout_user t;
>
> - memset(&t, 0, sizeof(t));
> __ip_vs_get_timeouts(net, &t);
> if (copy_to_user(user, &t, sizeof(t)) != 0)
> ret = -EFAULT;
Regards
--
Julian Anastasov <j...@ssi.bg>
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