From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
commit a53b72c83a4216f2eb883ed45a0cbce014b8e62d upstream.
The permission check in sock_diag_put_filterinfo is wrong, and it is so removed
from it's sources it is not clear why it is wrong. Move the computation
into packet_diag_dump and pass a bool of the result into sock_diag_filterinfo.
This does not yet correct the capability check but instead simply moves it to make
it clear what is going on.
Reported-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Xiangyu Lu <luxiangyu@xxxxxxxxxx>
---
include/linux/sock_diag.h | 2 +-
net/core/sock_diag.c | 4 ++--
net/packet/diag.c | 7 ++++++-
3 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h
index 302ab80..46cca4c 100644
--- a/include/linux/sock_diag.h
+++ b/include/linux/sock_diag.h
@@ -23,7 +23,7 @@ int sock_diag_check_cookie(void *sk, __u32 *cookie);
void sock_diag_save_cookie(void *sk, __u32 *cookie);
int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attr);
-int sock_diag_put_filterinfo(struct sock *sk,
+int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
struct sk_buff *skb, int attrtype);
#endif
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index 6a7fae2..c38e7a2 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -49,7 +49,7 @@ int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype)
}
EXPORT_SYMBOL_GPL(sock_diag_put_meminfo);
-int sock_diag_put_filterinfo(struct sock *sk,
+int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
struct sk_buff *skb, int attrtype)
{
struct nlattr *attr;
@@ -57,7 +57,7 @@ int sock_diag_put_filterinfo(struct sock *sk,
unsigned int len;
int err = 0;
- if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
+ if (!may_report_filterinfo) {
nla_reserve(skb, attrtype, 0);
return 0;
}
diff --git a/net/packet/diag.c b/net/packet/diag.c
index ec8b6e8..cbf7391 100644
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -127,6 +127,7 @@ static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
struct packet_diag_req *req,
+ bool may_report_filterinfo,
struct user_namespace *user_ns,
u32 portid, u32 seq, u32 flags, int sk_ino)
{
@@ -171,7 +172,8 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
goto out_nlmsg_trim;
if ((req->pdiag_show & PACKET_SHOW_FILTER) &&
- sock_diag_put_filterinfo(sk, skb, PACKET_DIAG_FILTER))
+ sock_diag_put_filterinfo(may_report_filterinfo, sk, skb,
+ PACKET_DIAG_FILTER))
goto out_nlmsg_trim;
return nlmsg_end(skb, nlh);
@@ -187,9 +189,11 @@ static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
struct packet_diag_req *req;
struct net *net;
struct sock *sk;
+ bool may_report_filterinfo;
net = sock_net(skb->sk);
req = nlmsg_data(cb->nlh);
+ may_report_filterinfo = ns_capable(net->user_ns, CAP_NET_ADMIN);
mutex_lock(&net->packet.sklist_lock);
sk_for_each(sk, &net->packet.sklist) {
@@ -199,6 +203,7 @@ static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
goto next;
if (sk_diag_fill(sk, skb, req,
+ may_report_filterinfo,
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
--
1.8.3.4
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html