diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt index 666594b43cff..6294b5186ae5 100644 --- a/Documentation/sysctl/net.txt +++ b/Documentation/sysctl/net.txt @@ -97,6 +97,14 @@ rmem_max The maximum receive socket buffer size in bytes. +tstamp_allow_data +----------------- +Allow processes to receive tx timestamps looped together with the original +packet contents. If disabled, transmit timestamp requests from unprivileged +processes are dropped unless socket option SOF_TIMESTAMPING_OPT_TSONLY is set. +Default: 1 (on) + + wmem_default ------------ diff --git a/include/net/sock.h b/include/net/sock.h index 15341499786c..511ef7c8889b 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2239,6 +2239,7 @@ bool sk_net_capable(const struct sock *sk, int cap); extern __u32 sysctl_wmem_max; extern __u32 sysctl_rmem_max; +extern int sysctl_tstamp_allow_data; extern int sysctl_optmem_max; extern __u32 sysctl_wmem_default; diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 65a3798f43e6..a5bff2767f15 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -74,6 +74,8 @@ #include #include #include +#include +#include struct kmem_cache *skbuff_head_cache __read_mostly; static struct kmem_cache *skbuff_fclone_cache __read_mostly; @@ -3690,11 +3692,28 @@ static void __skb_complete_tx_timestamp(struct sk_buff *skb, kfree_skb(skb); } +static bool skb_may_tx_timestamp(struct sock *sk, bool tsonly) +{ + bool ret; + + if (likely(sysctl_tstamp_allow_data || tsonly)) + return true; + + read_lock_bh(&sk->sk_callback_lock); + ret = sk->sk_socket && sk->sk_socket->file && + file_ns_capable(sk->sk_socket->file, &init_user_ns, CAP_NET_RAW); + read_unlock_bh(&sk->sk_callback_lock); + return ret; +} + void skb_complete_tx_timestamp(struct sk_buff *skb, struct skb_shared_hwtstamps *hwtstamps) { struct sock *sk = skb->sk; + if (!skb_may_tx_timestamp(sk, false)) + return; + /* take a reference to prevent skb_orphan() from freeing the socket */ sock_hold(sk); @@ -3712,7 +3731,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, struct sk_buff *skb; bool tsonly = sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TSONLY; - if (!sk) + if (!sk || !skb_may_tx_timestamp(sk, tsonly)) return; if (tsonly) diff --git a/net/core/sock.c b/net/core/sock.c index 1c7a33db1314..93c8b20c91e4 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -325,6 +325,8 @@ __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); EXPORT_SYMBOL(sysctl_optmem_max); +int sysctl_tstamp_allow_data __read_mostly = 1; + struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; EXPORT_SYMBOL_GPL(memalloc_socks); @@ -840,6 +842,7 @@ set_rcvbuf: ret = -EINVAL; break; } + if (val & SOF_TIMESTAMPING_OPT_ID && !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { if (sk->sk_protocol == IPPROTO_TCP) { diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index 31baba2a71ce..fde21d19e61b 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -321,6 +321,15 @@ static struct ctl_table net_core_table[] = { .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "tstamp_allow_data", + .data = &sysctl_tstamp_allow_data, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one + }, #ifdef CONFIG_RPS { .procname = "rps_sock_flow_entries",