2020-05-27 10:59:04

by Nathan Chancellor

Subject: [PATCH net] netfilter: conntrack: Pass value of ctinfo to __nf_conntrack_update

Clang warns:

net/netfilter/nf_conntrack_core.c:2068:21: warning: variable 'ctinfo' is
uninitialized when used here [-Wuninitialized]
nf_ct_set(skb, ct, ctinfo);
^~~~~~
net/netfilter/nf_conntrack_core.c:2024:2: note: variable 'ctinfo' is
declared here
enum ip_conntrack_info ctinfo;
^
1 warning generated.

nf_conntrack_update was split up into nf_conntrack_update and
__nf_conntrack_update, where the assignment of ctifno is in
nf_conntrack_update but it is used in __nf_conntrack_update.

Pass the value of ctinfo from nf_conntrack_update to
__nf_conntrack_update so that uninitialized memory is not used
and everything works properly.

Fixes: ee04805ff54a ("netfilter: conntrack: make conntrack userspace helpers work again")
Link: https://github.com/ClangBuiltLinux/linux/issues/1039
Signed-off-by: Nathan Chancellor <[email protected]>
---
net/netfilter/nf_conntrack_core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 08e0c19f6b39..e3b054a2f796 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -2017,11 +2017,11 @@ static void nf_conntrack_attach(struct sk_buff *nskb, const struct sk_buff *skb)
}

static int __nf_conntrack_update(struct net *net, struct sk_buff *skb,
- struct nf_conn *ct)
+ struct nf_conn *ct,
+ enum ip_conntrack_info ctinfo)
{
struct nf_conntrack_tuple_hash *h;
struct nf_conntrack_tuple tuple;
- enum ip_conntrack_info ctinfo;
struct nf_nat_hook *nat_hook;
unsigned int status;
int dataoff;
@@ -2146,7 +2146,7 @@ static int nf_conntrack_update(struct net *net, struct sk_buff *skb)
return 0;

if (!nf_ct_is_confirmed(ct)) {
- err = __nf_conntrack_update(net, skb, ct);
+ err = __nf_conntrack_update(net, skb, ct, ctinfo);
if (err < 0)
return err;
}

base-commit: a4976a3ef844c510ae9120290b23e9f3f47d6bce
--
2.27.0.rc0

2020-05-27 15:32:04

by Pablo Neira Ayuso

Subject: Re: [PATCH net] netfilter: conntrack: Pass value of ctinfo to __nf_conntrack_update

On Wed, May 27, 2020 at 01:10:39AM -0700, Nathan Chancellor wrote:
> Clang warns:
>
> net/netfilter/nf_conntrack_core.c:2068:21: warning: variable 'ctinfo' is
> uninitialized when used here [-Wuninitialized]
> nf_ct_set(skb, ct, ctinfo);
> ^~~~~~
> net/netfilter/nf_conntrack_core.c:2024:2: note: variable 'ctinfo' is
> declared here
> enum ip_conntrack_info ctinfo;
> ^
> 1 warning generated.
>
> nf_conntrack_update was split up into nf_conntrack_update and
> __nf_conntrack_update, where the assignment of ctifno is in
> nf_conntrack_update but it is used in __nf_conntrack_update.
>
> Pass the value of ctinfo from nf_conntrack_update to
> __nf_conntrack_update so that uninitialized memory is not used
> and everything works properly.

Applied, thanks.