[PATCH bpf-next] bpf/bpftool: add unprivileged_bpf_disabled check against value of 2

From: Milan Landaverde <milan@mdaverde.com>
To: unlisted-recipients:; (no To-header on input)
Cc: milan@mdaverde.com, "Alexei Starovoitov" <ast@kernel.org>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"Andrii Nakryiko" <andrii@kernel.org>,
	"Martin KaFai Lau" <kafai@fb.com>,
	"Song Liu" <songliubraving@fb.com>, "Yonghong Song" <yhs@fb.com>,
	"John Fastabend" <john.fastabend@gmail.com>,
	"KP Singh" <kpsingh@kernel.org>,
	"Quentin Monnet" <quentin@isovalent.com>,
	"Paul Chaignon" <paul@isovalent.com>,
	"Niklas Söderlund" <niklas.soderlund@corigine.com>,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH bpf-next] bpf/bpftool: add unprivileged_bpf_disabled check against value of 2
Date: Tue, 22 Mar 2022 10:49:45 -0400	[thread overview]
Message-ID: <20220322145012.1315376-1-milan@mdaverde.com> (raw)

In [1], we added a kconfig knob that can set
/proc/sys/kernel/unprivileged_bpf_disabled to 2

We now check against this value in bpftool feature probe

[1] https://lore.kernel.org/bpf/74ec548079189e4e4dffaeb42b8987bb3c852eee.1620765074.git.daniel@iogearbox.net

Signed-off-by: Milan Landaverde <milan@mdaverde.com>
---
 tools/bpf/bpftool/feature.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index c2f43a5d38e0..290998c82de1 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c
@@ -207,7 +207,10 @@ static void probe_unprivileged_disabled(void)
 			printf("bpf() syscall for unprivileged users is enabled\n");
 			break;
 		case 1:
-			printf("bpf() syscall restricted to privileged users\n");
+			printf("bpf() syscall restricted to privileged users (without recovery)\n");
+			break;
+		case 2:
+			printf("bpf() syscall restricted to privileged users (admin can change)\n");
 			break;
 		case -1:
 			printf("Unable to retrieve required privileges for bpf() syscall\n");
-- 
2.32.0

