Re: [PATCH] ip/link_vti6.c: Fix local/remote any handling

[Christian Langrock]

This seems to be the better solution, at least because i missed the case
where the function is called to alter a VTI.


BR,

Christian


Am 07.08.2017 um 17:12 schrieb Stephen Hemminger:
> On Mon, 7 Aug 2017 08:41:23 +0200
> Christian Langrock  wrote:
>
>> According to the IPv4 behavior of 'ip' it should be possible to omit the
>> arguments for local and remote address.
>> Without this patch omitting these parameters would lead to
>> uninitialized memory being interpreted as IPv6 addresses.
>>
>> Signed-off-by: Christian Langrock 
> I don't like extra flag values.  Why not just:
>
> diff --git a/ip/link_vti6.c b/ip/link_vti6.c
> index be4e33cee606..6ea1fc2306ce 100644
> --- a/ip/link_vti6.c
> +++ b/ip/link_vti6.c
> @@ -59,8 +59,8 @@ static int vti6_parse_opt(struct link_util *lu, int argc, 
> char **argv,
>   struct rtattr *tb[IFLA_MAX + 1];
>   struct rtattr *linkinfo[IFLA_INFO_MAX+1];
>   struct rtattr *vtiinfo[IFLA_VTI_MAX + 1];
> - struct in6_addr saddr;
> - struct in6_addr daddr;
> + struct in6_addr saddr = IN6ADDR_ANY_INIT;
> + struct in6_addr daddr = IN6ADDR_ANY_INIT;
>   unsigned int ikey = 0;
>   unsigned int okey = 0;
>   unsigned int link = 0;
> @@ -195,8 +195,11 @@ get_failed:
>  
>   addattr32(n, 1024, IFLA_VTI_IKEY, ikey);
>   addattr32(n, 1024, IFLA_VTI_OKEY, okey);
> - addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
> - addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
> +
> + if (memcmp(, _any, sizeof(in6addr_any)))
> + addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
> + if (memcmp(, _any, sizeof(in6addr_any)))
> + addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
>   addattr32(n, 1024, IFLA_VTI_FWMARK, fwmark);
>   if (link)
>   addattr32(n, 1024, IFLA_VTI_LINK, link);



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Re: [PATCH] ip/link_vti6.c: Fix local/remote any handling

[Stephen Hemminger]

On Mon, 7 Aug 2017 08:41:23 +0200
Christian Langrock  wrote:

> According to the IPv4 behavior of 'ip' it should be possible to omit the
> arguments for local and remote address.
> Without this patch omitting these parameters would lead to
> uninitialized memory being interpreted as IPv6 addresses.
> 
> Signed-off-by: Christian Langrock 

I don't like extra flag values.  Why not just:

diff --git a/ip/link_vti6.c b/ip/link_vti6.c
index be4e33cee606..6ea1fc2306ce 100644
--- a/ip/link_vti6.c
+++ b/ip/link_vti6.c
@@ -59,8 +59,8 @@ static int vti6_parse_opt(struct link_util *lu, int argc, 
char **argv,
struct rtattr *tb[IFLA_MAX + 1];
struct rtattr *linkinfo[IFLA_INFO_MAX+1];
struct rtattr *vtiinfo[IFLA_VTI_MAX + 1];
-   struct in6_addr saddr;
-   struct in6_addr daddr;
+   struct in6_addr saddr = IN6ADDR_ANY_INIT;
+   struct in6_addr daddr = IN6ADDR_ANY_INIT;
unsigned int ikey = 0;
unsigned int okey = 0;
unsigned int link = 0;
@@ -195,8 +195,11 @@ get_failed:
 
addattr32(n, 1024, IFLA_VTI_IKEY, ikey);
addattr32(n, 1024, IFLA_VTI_OKEY, okey);
-   addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
-   addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
+
+   if (memcmp(, _any, sizeof(in6addr_any)))
+   addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
+   if (memcmp(, _any, sizeof(in6addr_any)))
+   addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
addattr32(n, 1024, IFLA_VTI_FWMARK, fwmark);
if (link)
addattr32(n, 1024, IFLA_VTI_LINK, link);


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[PATCH] ip/link_vti6.c: Fix local/remote any handling

[Christian Langrock]

According to the IPv4 behavior of 'ip' it should be possible to omit the
arguments for local and remote address.
Without this patch omitting these parameters would lead to
uninitialized memory being interpreted as IPv6 addresses.

Signed-off-by: Christian Langrock 
---
 ip/link_vti6.c | 10 --
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/ip/link_vti6.c b/ip/link_vti6.c
index be4e33c..220b7df 100644
--- a/ip/link_vti6.c
+++ b/ip/link_vti6.c
@@ -60,7 +60,9 @@ static int vti6_parse_opt(struct link_util *lu, int
argc, char **argv,
 struct rtattr *linkinfo[IFLA_INFO_MAX+1];
 struct rtattr *vtiinfo[IFLA_VTI_MAX + 1];
 struct in6_addr saddr;
+bool use_saddr = false;
 struct in6_addr daddr;
+bool use_daddr = false;
 unsigned int ikey = 0;
 unsigned int okey = 0;
 unsigned int link = 0;
@@ -167,6 +169,7 @@ get_failed:
 
 get_prefix(, *argv, AF_INET6);
 memcpy(, addr.data, addr.bytelen);
+use_daddr = true;
 }
 } else if (!matches(*argv, "local")) {
 NEXT_ARG();
@@ -178,6 +181,7 @@ get_failed:
 
 get_prefix(, *argv, AF_INET6);
 memcpy(, addr.data, addr.bytelen);
+use_saddr = true;
 }
 } else if (!matches(*argv, "dev")) {
 NEXT_ARG();
@@ -195,8 +199,10 @@ get_failed:
 
 addattr32(n, 1024, IFLA_VTI_IKEY, ikey);
 addattr32(n, 1024, IFLA_VTI_OKEY, okey);
-addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
-addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
+if (use_saddr)
+addattr_l(n, 1024, IFLA_VTI_LOCAL, , sizeof(saddr));
+if (use_daddr)
+addattr_l(n, 1024, IFLA_VTI_REMOTE, , sizeof(daddr));
 addattr32(n, 1024, IFLA_VTI_FWMARK, fwmark);
 if (link)
 addattr32(n, 1024, IFLA_VTI_LINK, link);
-- 
2.7.4




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