4.20-stable review patch. If anyone has any objections, please let me know.
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From: Konstantin Khlebnikov khlebnikov@yandex-team.ru
[ Upstream commit 1ec17dbd90f8b638f41ee650558609c1af63dfa0 ]
Field idiag_ext in struct inet_diag_req_v2 used as bitmap of requested extensions has only 8 bits. Thus extensions starting from DCTCPINFO cannot be requested directly. Some of them included into response unconditionally or hook into some of lower 8 bits.
Extension INET_DIAG_CLASS_ID has not way to request from the beginning.
This patch bundle it with INET_DIAG_TCLASS (ipv6 tos), fixes space reservation, and documents behavior for other extensions.
Also this patch adds fallback to reporting socket priority. This filed is more widely used for traffic classification because ipv4 sockets automatically maps TOS to priority and default qdisc pfifo_fast knows about that. But priority could be changed via setsockopt SO_PRIORITY so INET_DIAG_TOS isn't enough for predicting class.
Also cgroup2 obsoletes net_cls classid (it always zero), but we cannot reuse this field for reporting cgroup2 id because it is 64-bit (ino+gen).
So, after this patch INET_DIAG_CLASS_ID will report socket priority for most common setup when net_cls isn't set and/or cgroup2 in use.
Fixes: 0888e372c37f ("net: inet: diag: expose sockets cgroup classid") Signed-off-by: Konstantin Khlebnikov khlebnikov@yandex-team.ru Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/uapi/linux/inet_diag.h | 16 +++++++++++----- net/ipv4/inet_diag.c | 10 +++++++++- net/sctp/diag.c | 1 + 3 files changed, 21 insertions(+), 6 deletions(-)
--- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -137,15 +137,21 @@ enum { INET_DIAG_TCLASS, INET_DIAG_SKMEMINFO, INET_DIAG_SHUTDOWN, - INET_DIAG_DCTCPINFO, - INET_DIAG_PROTOCOL, /* response attribute only */ + + /* + * Next extenstions cannot be requested in struct inet_diag_req_v2: + * its field idiag_ext has only 8 bits. + */ + + INET_DIAG_DCTCPINFO, /* request as INET_DIAG_VEGASINFO */ + INET_DIAG_PROTOCOL, /* response attribute only */ INET_DIAG_SKV6ONLY, INET_DIAG_LOCALS, INET_DIAG_PEERS, INET_DIAG_PAD, - INET_DIAG_MARK, - INET_DIAG_BBRINFO, - INET_DIAG_CLASS_ID, + INET_DIAG_MARK, /* only with CAP_NET_ADMIN */ + INET_DIAG_BBRINFO, /* request as INET_DIAG_VEGASINFO */ + INET_DIAG_CLASS_ID, /* request as INET_DIAG_TCLASS */ INET_DIAG_MD5SIG, __INET_DIAG_MAX, }; --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -108,6 +108,7 @@ static size_t inet_sk_attr_size(struct s + nla_total_size(1) /* INET_DIAG_TOS */ + nla_total_size(1) /* INET_DIAG_TCLASS */ + nla_total_size(4) /* INET_DIAG_MARK */ + + nla_total_size(4) /* INET_DIAG_CLASS_ID */ + nla_total_size(sizeof(struct inet_diag_meminfo)) + nla_total_size(sizeof(struct inet_diag_msg)) + nla_total_size(SK_MEMINFO_VARS * sizeof(u32)) @@ -287,12 +288,19 @@ int inet_sk_diag_fill(struct sock *sk, s goto errout; }
- if (ext & (1 << (INET_DIAG_CLASS_ID - 1))) { + if (ext & (1 << (INET_DIAG_CLASS_ID - 1)) || + ext & (1 << (INET_DIAG_TCLASS - 1))) { u32 classid = 0;
#ifdef CONFIG_SOCK_CGROUP_DATA classid = sock_cgroup_classid(&sk->sk_cgrp_data); #endif + /* Fallback to socket priority if class id isn't set. + * Classful qdiscs use it as direct reference to class. + * For cgroup2 classid is always zero. + */ + if (!classid) + classid = sk->sk_priority;
if (nla_put_u32(skb, INET_DIAG_CLASS_ID, classid)) goto errout; --- a/net/sctp/diag.c +++ b/net/sctp/diag.c @@ -256,6 +256,7 @@ static size_t inet_assoc_attr_size(struc + nla_total_size(1) /* INET_DIAG_TOS */ + nla_total_size(1) /* INET_DIAG_TCLASS */ + nla_total_size(4) /* INET_DIAG_MARK */ + + nla_total_size(4) /* INET_DIAG_CLASS_ID */ + nla_total_size(addrlen * asoc->peer.transport_count) + nla_total_size(addrlen * addrcnt) + nla_total_size(sizeof(struct inet_diag_meminfo))