Re: [PATCH net-next] bpf: fix the printing of ifindex

[David Miller]

From: William Tu 
Date: Wed,  2 Aug 2017 08:43:52 -0700

> Save the ifindex before it gets zeroed so the invalid
> ifindex can be printed out.
> 
> Signed-off-by: William Tu 

Applied, thanks.

Re: [PATCH net-next] bpf: fix the printing of ifindex

[John Fastabend]

On 08/02/2017 08:43 AM, William Tu wrote:
> Save the ifindex before it gets zeroed so the invalid
> ifindex can be printed out.
> 
> Signed-off-by: William Tu 
> ---


Thanks!

Acked-by: John Fastabend 

Re: [PATCH net-next] bpf: fix the printing of ifindex

[Daniel Borkmann]

On 08/02/2017 05:43 PM, William Tu wrote:

Save the ifindex before it gets zeroed so the invalid
ifindex can be printed out.

Signed-off-by: William Tu 


Acked-by: Daniel Borkmann 


  net/core/filter.c | 10 ++
  1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index 7e9708653c6f..78d00933dbe7 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2509,15 +2509,16 @@ int xdp_do_redirect(struct net_device *dev, struct 
xdp_buff *xdp,
  {
struct redirect_info *ri = this_cpu_ptr(_info);
struct net_device *fwd;
+   u32 index = ri->ifindex;

if (ri->map)
return xdp_do_redirect_map(dev, xdp, xdp_prog);

-   fwd = dev_get_by_index_rcu(dev_net(dev), ri->ifindex);
+   fwd = dev_get_by_index_rcu(dev_net(dev), index);
ri->ifindex = 0;
ri->map = NULL;


Unrelated, but setting ri->map to NULL is not really needed here
given we have the ri->map test earlier.


if (unlikely(!fwd)) {
-   bpf_warn_invalid_xdp_redirect(ri->ifindex);
+   bpf_warn_invalid_xdp_redirect(index);
return -EINVAL;
}

@@ -2531,11 +2532,12 @@ int xdp_do_generic_redirect(struct net_device *dev, 
struct sk_buff *skb)
  {
struct redirect_info *ri = this_cpu_ptr(_info);
unsigned int len;
+   u32 index = ri->ifindex;

-   dev = dev_get_by_index_rcu(dev_net(dev), ri->ifindex);
+   dev = dev_get_by_index_rcu(dev_net(dev), index);
ri->ifindex = 0;
if (unlikely(!dev)) {
-   bpf_warn_invalid_xdp_redirect(ri->ifindex);
+   bpf_warn_invalid_xdp_redirect(index);
goto err;
}

[PATCH net-next] bpf: fix the printing of ifindex

[William Tu]

Save the ifindex before it gets zeroed so the invalid
ifindex can be printed out.

Signed-off-by: William Tu 
---
 net/core/filter.c | 10 ++
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index 7e9708653c6f..78d00933dbe7 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2509,15 +2509,16 @@ int xdp_do_redirect(struct net_device *dev, struct 
xdp_buff *xdp,
 {
struct redirect_info *ri = this_cpu_ptr(_info);
struct net_device *fwd;
+   u32 index = ri->ifindex;
 
if (ri->map)
return xdp_do_redirect_map(dev, xdp, xdp_prog);
 
-   fwd = dev_get_by_index_rcu(dev_net(dev), ri->ifindex);
+   fwd = dev_get_by_index_rcu(dev_net(dev), index);
ri->ifindex = 0;
ri->map = NULL;
if (unlikely(!fwd)) {
-   bpf_warn_invalid_xdp_redirect(ri->ifindex);
+   bpf_warn_invalid_xdp_redirect(index);
return -EINVAL;
}
 
@@ -2531,11 +2532,12 @@ int xdp_do_generic_redirect(struct net_device *dev, 
struct sk_buff *skb)
 {
struct redirect_info *ri = this_cpu_ptr(_info);
unsigned int len;
+   u32 index = ri->ifindex;
 
-   dev = dev_get_by_index_rcu(dev_net(dev), ri->ifindex);
+   dev = dev_get_by_index_rcu(dev_net(dev), index);
ri->ifindex = 0;
if (unlikely(!dev)) {
-   bpf_warn_invalid_xdp_redirect(ri->ifindex);
+   bpf_warn_invalid_xdp_redirect(index);
goto err;
}
 
-- 
2.7.4