diff mbox series

[net-next,01/12] bpf: Unmask upper DSCP bits in bpf_fib_lookup() helper

Message ID 20240821125251.1571445-2-idosch@nvidia.com (mailing list archive)
State Accepted
Commit ef434fae72287a9cd0f7b85ad1701b998cce800b
Delegated to: Netdev Maintainers
Headers show
Series Unmask upper DSCP bits - part 1 | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 8 maintainers not CCed: andrii@kernel.org sdf@fomichev.me eddyz87@gmail.com haoluo@google.com jolsa@kernel.org song@kernel.org yonghong.song@linux.dev kpsingh@kernel.org
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 42 this patch: 42
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 15 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 6 this patch: 6
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-22--03-00 (tests: 711)

Commit Message

Ido Schimmel Aug. 21, 2024, 12:52 p.m. UTC
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@nvidia.com>
---
 net/core/filter.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Guillaume Nault Aug. 21, 2024, 2:35 p.m. UTC | #1
On Wed, Aug 21, 2024 at 03:52:40PM +0300, Ido Schimmel wrote:
> 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.

Reviewed-by: Guillaume Nault <gnault@redhat.com>
diff mbox series

Patch

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;