netdev - [PATCH net-next 01/12] bpf: Unmask upper DSCP bits in bpf_fib

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240821125251.1571445-2-idosch@nvidia.com>
Date: Wed, 21 Aug 2024 15:52:40 +0300
From: Ido Schimmel <idosch@...dia.com>
To: <netdev@...r.kernel.org>
CC: <davem@...emloft.net>, <kuba@...nel.org>, <pabeni@...hat.com>,
	<edumazet@...gle.com>, <gnault@...hat.com>, <dsahern@...nel.org>,
	<fw@...len.de>, <martin.lau@...ux.dev>, <daniel@...earbox.net>,
	<john.fastabend@...il.com>, <ast@...nel.org>, <pablo@...filter.org>,
	<kadlec@...filter.org>, <willemdebruijn.kernel@...il.com>,
	<bpf@...r.kernel.org>, <netfilter-devel@...r.kernel.org>,
	<coreteam@...filter.org>, Ido Schimmel <idosch@...dia.com>
Subject: [PATCH net-next 01/12] bpf: Unmask upper DSCP bits in bpf_fib_lookup() helper

The helper performs a FIB lookup according to the parameters in the
'params' argument, one of which is 'tos'. According to the test in
test_tc_neigh_fib.c, it seems that BPF programs are expected to
initialize the 'tos' field to the full 8 bit DS field from the IPv4
header.

Unmask the upper DSCP bits before invoking the IPv4 FIB lookup APIs so
that in the future the lookup could be performed according to the full
DSCP value.

No functional changes intended since the upper DSCP bits are masked when
comparing against the TOS selectors in FIB rules and routes.

Signed-off-by: Ido Schimmel <idosch@...dia.com>
---
 net/core/filter.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index f3c72cf86099..89f56fac48fb 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -84,6 +84,7 @@
 #include <net/netkit.h>
 #include <linux/un.h>
 #include <net/xdp_sock_drv.h>
+#include <net/inet_dscp.h>
 
 #include "dev.h"
 
@@ -5899,7 +5900,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 		fl4.flowi4_iif = params->ifindex;
 		fl4.flowi4_oif = 0;
 	}
-	fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
+	fl4.flowi4_tos = params->tos & INET_DSCP_MASK;
 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
 	fl4.flowi4_flags = 0;
 
-- 
2.46.0