From: Johannes Berg <johannes.b...@intel.com>
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
crypto/crypto_user.c | 3 +-
drivers/infiniband/core/netlink.c | 3 +-
drivers/scsi/scsi_netlink.c | 2 +-
include/linux/netlink.h | 10 ++++++-
include/net/netlink.h | 3 +-
include/uapi/linux/netlink.h | 26 +++++++++++++++++
kernel/audit.c | 2 +-
net/core/rtnetlink.c | 3 +-
net/core/sock_diag.c | 3 +-
net/hsr/hsr_netlink.c | 4 +--
net/netfilter/ipset/ip_set_core.c | 2 +-
net/netfilter/nfnetlink.c | 18 ++++++------
net/netlink/af_netlink.c | 60 ++++++++++++++++++++++++++++++++++-----
net/netlink/genetlink.c | 3 +-
net/xfrm/xfrm_user.c | 3 +-
15 files changed, 117 insertions(+), 28 deletions(-)
diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index a90404a0c5ff..4d4433e80866 100644
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -483,7 +483,8 @@ static const struct crypto_link {
[CRYPTO_MSG_DELRNG - CRYPTO_MSG_BASE] = { .doit = crypto_del_rng },
};
-static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
struct nlattr *attrs[CRYPTOCFGA_MAX+1];
const struct crypto_link *link;
diff --git a/drivers/infiniband/core/netlink.c
b/drivers/infiniband/core/netlink.c
index 10469b0088b5..679d65430113 100644
--- a/drivers/infiniband/core/netlink.c
+++ b/drivers/infiniband/core/netlink.c
@@ -146,7 +146,8 @@ int ibnl_put_attr(struct sk_buff *skb, struct nlmsghdr *nlh,
}
EXPORT_SYMBOL(ibnl_put_attr);
-static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
struct ibnl_client *client;
int type = nlh->nlmsg_type;
diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c
index 109802f776ed..50e624fb8307 100644
--- a/drivers/scsi/scsi_netlink.c
+++ b/drivers/scsi/scsi_netlink.c
@@ -111,7 +111,7 @@ scsi_nl_rcv_msg(struct sk_buff *skb)
next_msg:
if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
skb_pull(skb, rlen);
}
diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index da14ab61f363..662f343dc68b 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -62,11 +62,19 @@ netlink_kernel_create(struct net *net, int unit, struct
netlink_kernel_cfg *cfg)
return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
}
+struct netlink_ext_err {
+ const char *msg;
+ u32 ext_code;
+ u32 msg_offset;
+ u16 attr;
+};
+
extern void netlink_kernel_release(struct sock *sk);
extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int
group);
-extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
+extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
+ const struct netlink_ext_err *exterr);
extern int netlink_has_listeners(struct sock *sk, unsigned int group);
extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32
portid, int nonblock);
diff --git a/include/net/netlink.h b/include/net/netlink.h
index b239fcd33d80..f06c2e00ebc3 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -233,7 +233,8 @@ struct nl_info {
};
int netlink_rcv_skb(struct sk_buff *skb,
- int (*cb)(struct sk_buff *, struct nlmsghdr *));
+ int (*cb)(struct sk_buff *, struct nlmsghdr *,
+ struct netlink_ext_err *));
int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
unsigned int group, int report, gfp_t flags);
diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h
index b2c9c26ea30f..0ef970e6f9f5 100644
--- a/include/uapi/linux/netlink.h
+++ b/include/uapi/linux/netlink.h
@@ -101,6 +101,31 @@ struct nlmsghdr {
struct nlmsgerr {
int error;
struct nlmsghdr msg;
+ /*
+ * followed by the message contents unless NETLINK_CAP_ACK was set,
+ * message length is aligned with NLMSG_ALIGN()
+ */
+ /*
+ * followed by TLVs defined in enum nlmsgerr_attrs
+ * if NETLINK_EXT_ACK was set
+ */
+};
+
+/**
+ * enum nlmsgerr_attrs - netlink error message attributes
+ * @NLMSGERR_ATTR_UNUSED: unused
+ * @NLMSGERR_ATTR_MSG: error message string (string)
+ * @NLMSGERR_ATTR_OFFS: error offset in the original message (u32)
+ * @NLMSGERR_ATTR_CODE: extended per-subsystem error code (u32)
+ * @NLMSGERR_ATTR_ATTR: top-level attribute that caused the error
+ * (or is missing, u16)
+ */
+enum nlmsgerr_attrs {
+ NLMSGERR_ATTR_UNUSED,
+ NLMSGERR_ATTR_MSG,
+ NLMSGERR_ATTR_OFFS,
+ NLMSGERR_ATTR_CODE,
+ NLMSGERR_ATTR_ATTR,
};
#define NETLINK_ADD_MEMBERSHIP 1
@@ -115,6 +140,7 @@ struct nlmsgerr {
#define NETLINK_LISTEN_ALL_NSID 8
#define NETLINK_LIST_MEMBERSHIPS 9
#define NETLINK_CAP_ACK 10
+#define NETLINK_EXT_ACK 11
struct nl_pktinfo {
__u32 group;
diff --git a/kernel/audit.c b/kernel/audit.c
index e794544f5e63..d5f0e1d92ea2 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1264,7 +1264,7 @@ static void audit_receive_skb(struct sk_buff *skb)
err = audit_receive_msg(skb, nlh);
/* if err or if this message says it wants a response */
if (err || (nlh->nlmsg_flags & NLM_F_ACK))
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
nlh = nlmsg_next(nlh, &len);
}
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index c4e84c558240..e3e693831e43 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -4046,7 +4046,8 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct
netlink_callback *cb)
/* Process one rtnetlink message. */
-static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
struct net *net = sock_net(skb->sk);
rtnl_doit_func doit;
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index 6b10573cc9fa..3348a7b976ce 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -246,7 +246,8 @@ static int __sock_diag_cmd(struct sk_buff *skb, struct
nlmsghdr *nlh)
return err;
}
-static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
int ret;
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
index 1ab30e7d3f99..81dac16933fc 100644
--- a/net/hsr/hsr_netlink.c
+++ b/net/hsr/hsr_netlink.c
@@ -350,7 +350,7 @@ static int hsr_get_node_status(struct sk_buff *skb_in,
struct genl_info *info)
return 0;
invalid:
- netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+ netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
nla_put_failure:
@@ -432,7 +432,7 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct
genl_info *info)
return 0;
invalid:
- netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+ netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
nla_put_failure:
diff --git a/net/netfilter/ipset/ip_set_core.c
b/net/netfilter/ipset/ip_set_core.c
index c296f9b606d4..26356bf8cebf 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1305,7 +1305,7 @@ ip_set_dump_start(struct sk_buff *skb, struct
netlink_callback *cb)
* manually :-(
*/
if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(cb->skb, nlh, ret);
+ netlink_ack(cb->skb, nlh, ret, NULL);
return ret;
}
}
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 68eda920160e..50f1ef27baab 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -148,7 +148,8 @@ int nfnetlink_unicast(struct sk_buff *skb, struct net *net,
u32 portid,
EXPORT_SYMBOL_GPL(nfnetlink_unicast);
/* Process one complete nfnetlink message. */
-static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
struct net *net = sock_net(skb->sk);
const struct nfnl_callback *nc;
@@ -261,7 +262,7 @@ static void nfnl_err_deliver(struct list_head *err_list,
struct sk_buff *skb)
struct nfnl_err *nfnl_err, *next;
list_for_each_entry_safe(nfnl_err, next, err_list, head) {
- netlink_ack(skb, nfnl_err->nlh, nfnl_err->err);
+ netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, NULL);
nfnl_err_del(nfnl_err);
}
}
@@ -304,20 +305,20 @@ static void nfnetlink_rcv_batch(struct sk_buff *skb,
struct nlmsghdr *nlh,
#endif
{
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -EOPNOTSUPP);
+ netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
return kfree_skb(skb);
}
}
if (!ss->commit || !ss->abort) {
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -EOPNOTSUPP);
+ netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
return kfree_skb(skb);
}
if (genid && ss->valid_genid && !ss->valid_genid(net, genid)) {
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -ERESTART);
+ netlink_ack(oskb, nlh, -ERESTART, NULL);
return kfree_skb(skb);
}
@@ -407,7 +408,8 @@ static void nfnetlink_rcv_batch(struct sk_buff *skb, struct
nlmsghdr *nlh,
* pointing to the batch header.
*/
nfnl_err_reset(&err_list);
- netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM);
+ netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM,
+ NULL);
status |= NFNL_BATCH_FAILURE;
goto done;
}
@@ -467,7 +469,7 @@ static void nfnetlink_rcv_skb_batch(struct sk_buff *skb,
struct nlmsghdr *nlh)
err = nla_parse(cda, NFNL_BATCH_MAX, attr, attrlen, nfnl_batch_policy);
if (err < 0) {
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
return;
}
if (cda[NFNL_BATCH_GENID])
@@ -493,7 +495,7 @@ static void nfnetlink_rcv(struct sk_buff *skb)
return;
if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
- netlink_ack(skb, nlh, -EPERM);
+ netlink_ack(skb, nlh, -EPERM, NULL);
return;
}
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 7b73c7c161a9..532d906af3be 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -85,6 +85,7 @@ struct listeners {
#define NETLINK_F_RECV_NO_ENOBUFS 0x8
#define NETLINK_F_LISTEN_ALL_NSID 0x10
#define NETLINK_F_CAP_ACK 0x20
+#define NETLINK_F_EXT_ACK 0x40
static inline int netlink_is_kernel(struct sock *sk)
{
@@ -1619,6 +1620,13 @@ static int netlink_setsockopt(struct socket *sock, int
level, int optname,
nlk->flags &= ~NETLINK_F_CAP_ACK;
err = 0;
break;
+ case NETLINK_EXT_ACK:
+ if (val)
+ nlk->flags |= NETLINK_F_EXT_ACK;
+ else
+ nlk->flags &= ~NETLINK_F_EXT_ACK;
+ err = 0;
+ break;
default:
err = -ENOPROTOOPT;
}
@@ -1703,6 +1711,16 @@ static int netlink_getsockopt(struct socket *sock, int
level, int optname,
return -EFAULT;
err = 0;
break;
+ case NETLINK_EXT_ACK:
+ if (len < sizeof(int))
+ return -EINVAL;
+ len = sizeof(int);
+ val = nlk->flags & NETLINK_F_EXT_ACK ? 1 : 0;
+ if (put_user(len, optlen) ||
+ put_user(val, optval))
+ return -EFAULT;
+ err = 0;
+ break;
default:
err = -ENOPROTOOPT;
}
@@ -2234,7 +2252,8 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff
*skb,
}
EXPORT_SYMBOL(__netlink_dump_start);
-void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
+void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
+ const struct netlink_ext_err *exterr)
{
struct sk_buff *skb;
struct nlmsghdr *rep;
@@ -2243,10 +2262,22 @@ void netlink_ack(struct sk_buff *in_skb, struct
nlmsghdr *nlh, int err)
struct netlink_sock *nlk = nlk_sk(NETLINK_CB(in_skb).sk);
/* Error messages get the original request appened, unless the user
- * requests to cap the error message.
+ * requests to cap the error message, and get extra error data if
+ * requested.
*/
- if (!(nlk->flags & NETLINK_F_CAP_ACK) && err)
- payload += nlmsg_len(nlh);
+ if (err) {
+ if (!(nlk->flags & NETLINK_F_CAP_ACK))
+ payload += nlmsg_len(nlh);
+ if (nlk->flags & NETLINK_F_EXT_ACK) {
+ if (exterr && exterr->msg)
+ payload +=
+ nla_total_size(strlen(exterr->msg) + 1);
+ if (exterr && exterr->msg_offset)
+ payload += nla_total_size(sizeof(u32));
+ if (exterr && exterr->attr)
+ payload += nla_total_size(sizeof(u16));
+ }
+ }
skb = nlmsg_new(payload, GFP_KERNEL);
if (!skb) {
@@ -2268,13 +2299,28 @@ void netlink_ack(struct sk_buff *in_skb, struct
nlmsghdr *nlh, int err)
errmsg = nlmsg_data(rep);
errmsg->error = err;
memcpy(&errmsg->msg, nlh, payload > sizeof(*errmsg) ? nlh->nlmsg_len :
sizeof(*nlh));
+
+ if (nlk->flags & NETLINK_F_EXT_ACK) {
+ if (exterr && exterr->msg)
+ WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG,
+ exterr->msg));
+ if (exterr && exterr->msg_offset)
+ WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,
+ exterr->msg_offset));
+ if (exterr && exterr->attr)
+ WARN_ON(nla_put_u16(skb, NLMSGERR_ATTR_ATTR,
+ exterr->attr));
+ }
+
netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid,
MSG_DONTWAIT);
}
EXPORT_SYMBOL(netlink_ack);
int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
- struct nlmsghdr *))
+ struct nlmsghdr *,
+ struct netlink_ext_err *))
{
+ struct netlink_ext_err exterr = {};
struct nlmsghdr *nlh;
int err;
@@ -2295,13 +2341,13 @@ int netlink_rcv_skb(struct sk_buff *skb, int
(*cb)(struct sk_buff *,
if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
goto ack;
- err = cb(skb, nlh);
+ err = cb(skb, nlh, &exterr);
if (err == -EINTR)
goto skip;
ack:
if (nlh->nlmsg_flags & NLM_F_ACK || err)
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, &exterr);
skip:
msglen = NLMSG_ALIGN(nlh->nlmsg_len);
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index fb6e10fdb217..48f21dc467a7 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -605,7 +605,8 @@ static int genl_family_rcv_msg(const struct genl_family
*family,
return err;
}
-static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
const struct genl_family *family;
int err;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 9705c279494b..de0c672c771b 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2441,7 +2441,8 @@ static const struct xfrm_link {
[XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo },
};
-static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_err *exterr)
{
struct net *net = sock_net(skb->sk);
struct nlattr *attrs[XFRMA_MAX+1];
--
2.11.0
