[RFC 1/7] netlink: Add allocation flag to netlink_unicast()

Though netlink_broadcast() has allocation flag which can specify memory allocation type (ex. GFP_KERNEL/GFP_ATOMIC), netlink_unicast() does not have it. This can cause "BUG: sleeping function called from invalid context at" with CONFIG_DEBUG_ATOMIC_SLEEP enabled kernel when calling netlink_unicast() inside RCU read-side section and not in IRQ. This patch adds an allocation flag to netlink_unicast(). At this moment, the allocation flag could be zero to imply gfp_any(). This is a temporal functionality for stepwise modification and removed at the end of the series of patches. Signed-off-by: Masashi Honma <masashi.honma(a)gmail.com&gt; --- drivers/connector/connector.c | 2 +- include/linux/netlink.h | 3 ++- include/net/netlink.h | 2 +- kernel/audit.c | 9 +++++---- net/core/rtnetlink.c | 2 +- net/ipv4/fib_frontend.c | 2 +- net/ipv4/inet_diag.c | 2 +- net/ipv4/udp_diag.c | 2 +- net/netfilter/ipset/ip_set_core.c | 11 +++++++---- net/netfilter/nf_conntrack_netlink.c | 9 ++++++--- net/netfilter/nfnetlink.c | 2 +- net/netfilter/nfnetlink_acct.c | 2 +- net/netfilter/nfnetlink_cthelper.c | 2 +- net/netfilter/nfnetlink_cttimeout.c | 5 +++-- net/netfilter/nft_compat.c | 4 ++-- net/netlink/af_netlink.c | 12 +++++++----- net/sctp/sctp_diag.c | 2 +- net/unix/diag.c | 2 +- samples/connector/cn_test.c | 2 +- 19 files changed, 44 insertions(+), 33 deletions(-) diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c index 25693b0..44470e6 100644 --- a/drivers/connector/connector.c +++ b/drivers/connector/connector.c @@ -125,7 +125,7 @@ int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, u32 __group, return netlink_broadcast(dev->nls, skb, portid, group, gfp_mask); return netlink_unicast(dev->nls, skb, portid, - !gfpflags_allow_blocking(gfp_mask)); + !gfpflags_allow_blocking(gfp_mask), gfp_mask); } EXPORT_SYMBOL_GPL(cn_netlink_send_mult); diff --git a/include/linux/netlink.h b/include/linux/netlink.h index da14ab6..f90d24a 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -69,7 +69,8 @@ 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 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); +extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, + int nonblock, gfp_t allocation); extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid, __u32 group, gfp_t allocation); extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, diff --git a/include/net/netlink.h b/include/net/netlink.h index 254a0fc..898e449 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -590,7 +590,7 @@ static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid { int err; - err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT); + err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT, 0); if (err > 0) err = 0; diff --git a/kernel/audit.c b/kernel/audit.c index 8d528f9..131577d 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -411,7 +411,7 @@ static void kauditd_send_skb(struct sk_buff *skb) restart: /* take a reference in case we can't send it and we want to hold it */ skb_get(skb); - err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); + err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0, gfp_any()); if (err < 0) { pr_err("netlink_unicast sending to audit_pid=%d returned error: %d\n", audit_pid, err); @@ -547,7 +547,7 @@ int audit_send_list(void *_dest) mutex_unlock(&audit_cmd_mutex); while ((skb = __skb_dequeue(&dest->q)) != NULL) - netlink_unicast(aunet->nlsk, skb, dest->portid, 0); + netlink_unicast(aunet->nlsk, skb, dest->portid, 0, gfp_any()); put_net(net); kfree(dest); @@ -591,7 +591,7 @@ static int audit_send_reply_thread(void *arg) /* Ignore failure. It'll only happen if the sender goes away, because our timeout is set to infinite. */ - netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0); + netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0, gfp_any()); put_net(net); kfree(reply); return 0; @@ -814,7 +814,8 @@ static int audit_replace(pid_t pid) if (!skb) return -ENOMEM; - return netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); + return netlink_unicast(audit_sock, skb, audit_nlk_portid, 0, + GFP_KERNEL); } static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index eb49ca2..3433633f 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -649,7 +649,7 @@ int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned int g atomic_inc(&skb->users); netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL); if (echo) - err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT); + err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT, GFP_KERNEL); return err; } diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index ef2ebeb..6a4286f 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1096,7 +1096,7 @@ static void nl_fib_input(struct sk_buff *skb) portid = NETLINK_CB(skb).portid; /* netlink portid */ NETLINK_CB(skb).portid = 0; /* from kernel */ NETLINK_CB(skb).dst_group = 0; /* unicast */ - netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT); + netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT, GFP_KERNEL); } static int __net_init nl_fib_lookup_init(struct net *net) diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 38c2c47..2963b5f 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -441,7 +441,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, goto out; } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (err > 0) err = 0; diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c index 3d5ccf4..69ac502 100644 --- a/net/ipv4/udp_diag.c +++ b/net/ipv4/udp_diag.c @@ -83,7 +83,7 @@ static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb, goto out; } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (err > 0) err = 0; out: diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index a748b0c..fcbe122 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1510,7 +1510,7 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set, *errline = lineno; netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); /* Signal netlink not to send its ACK/errmsg. */ return -EINTR; } @@ -1695,7 +1695,8 @@ static int ip_set_header(struct net *net, struct sock *ctnl, goto nla_put_failure; nlmsg_end(skb2, nlh2); - ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (ret < 0) return ret; @@ -1755,7 +1756,8 @@ static int ip_set_type(struct net *net, struct sock *ctnl, struct sk_buff *skb, nlmsg_end(skb2, nlh2); pr_debug("Send TYPE, nlmsg_len: %u\n", nlh2->nlmsg_len); - ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (ret < 0) return ret; @@ -1798,7 +1800,8 @@ static int ip_set_protocol(struct net *net, struct sock *ctnl, goto nla_put_failure; nlmsg_end(skb2, nlh2); - ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (ret < 0) return ret; diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index a18d1ce..6537e8d 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1224,7 +1224,8 @@ static int ctnetlink_get_conntrack(struct net *net, struct sock *ctnl, if (err <= 0) goto free; - err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (err < 0) goto out; @@ -2083,7 +2084,8 @@ static int ctnetlink_stat_ct(struct net *net, struct sock *ctnl, if (err <= 0) goto free; - err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (err < 0) goto out; @@ -2821,7 +2823,8 @@ static int ctnetlink_get_expect(struct net *net, struct sock *ctnl, if (err <= 0) goto free; - err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (err < 0) goto out; diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 2278d9a..f6193e7 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -143,7 +143,7 @@ EXPORT_SYMBOL_GPL(nfnetlink_set_err); int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid, int flags) { - return netlink_unicast(net->nfnl, skb, portid, flags); + return netlink_unicast(net->nfnl, skb, portid, flags, 0); } EXPORT_SYMBOL_GPL(nfnetlink_unicast); diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c index 1b4de4b..8b5bd59 100644 --- a/net/netfilter/nfnetlink_acct.c +++ b/net/netfilter/nfnetlink_acct.c @@ -311,7 +311,7 @@ static int nfnl_acct_get(struct net *net, struct sock *nfnl, break; } ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (ret > 0) ret = 0; diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index e924e95..e46b7cd 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -559,7 +559,7 @@ static int nfnl_cthelper_get(struct net *net, struct sock *nfnl, } ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (ret > 0) ret = 0; diff --git a/net/netfilter/nfnetlink_cttimeout.c b/net/netfilter/nfnetlink_cttimeout.c index 3c84f14..813eb8a 100644 --- a/net/netfilter/nfnetlink_cttimeout.c +++ b/net/netfilter/nfnetlink_cttimeout.c @@ -279,7 +279,7 @@ static int cttimeout_get_timeout(struct net *net, struct sock *ctnl, break; } ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (ret > 0) ret = 0; @@ -496,7 +496,8 @@ static int cttimeout_default_get(struct net *net, struct sock *ctnl, err = -ENOMEM; goto err; } - ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); + ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, + MSG_DONTWAIT, GFP_KERNEL); if (ret > 0) ret = 0; diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c index 6228c42..7de9ea4 100644 --- a/net/netfilter/nft_compat.c +++ b/net/netfilter/nft_compat.c @@ -582,8 +582,8 @@ static int nfnl_compat_get(struct net *net, struct sock *nfnl, return -ENOSPC; } - ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, - MSG_DONTWAIT); + ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT, + GFP_KERNEL); if (ret > 0) ret = 0; diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 627f898..c68bf74 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1220,14 +1220,14 @@ static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb, return ret; } -int netlink_unicast(struct sock *ssk, struct sk_buff *skb, - u32 portid, int nonblock) +int netlink_unicast(struct sock *ssk, struct sk_buff *skb, u32 portid, + int nonblock, gfp_t allocation) { struct sock *sk; int err; long timeo; - skb = netlink_trim(skb, gfp_any()); + skb = netlink_trim(skb, allocation ? allocation : gfp_any()); timeo = sock_sndtimeo(ssk, nonblock); retry: @@ -1783,7 +1783,8 @@ static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) atomic_inc(&skb->users); netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL); } - err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT); + err = netlink_unicast(sk, skb, dst_portid, + msg->msg_flags & MSG_DONTWAIT, GFP_KERNEL); out: scm_destroy(&scm); @@ -2250,7 +2251,8 @@ 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)); - netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); + netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, + MSG_DONTWAIT, GFP_KERNEL); } EXPORT_SYMBOL(netlink_ack); diff --git a/net/sctp/sctp_diag.c b/net/sctp/sctp_diag.c index f69edcf..4e66405 100644 --- a/net/sctp/sctp_diag.c +++ b/net/sctp/sctp_diag.c @@ -259,7 +259,7 @@ static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p) } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (err > 0) err = 0; out: diff --git a/net/unix/diag.c b/net/unix/diag.c index 4d96797..5e7e952 100644 --- a/net/unix/diag.c +++ b/net/unix/diag.c @@ -280,7 +280,7 @@ again: goto again; } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, - MSG_DONTWAIT); + MSG_DONTWAIT, GFP_KERNEL); if (err > 0) err = 0; out: diff --git a/samples/connector/cn_test.c b/samples/connector/cn_test.c index d12cc94..640d11b 100644 --- a/samples/connector/cn_test.c +++ b/samples/connector/cn_test.c @@ -116,7 +116,7 @@ static int cn_test_want_notify(void) NETLINK_CB(skb).dst_group = ctl->group; //netlink_broadcast(nls, skb, 0, ctl->group, GFP_ATOMIC); - netlink_unicast(nls, skb, 0, 0); + netlink_unicast(nls, skb, 0, 0, GFP_ATOMIC); pr_info("request was sent: group=0x%x\n", ctl->group); -- 2.7.4