[PATCH AUTOSEL 5.9 02/21] tools, bpftool: Avoid array index warnings.

From: Sasha Levin
Date: Tue Nov 17 2020 - 07:57:54 EST


From: Ian Rogers <irogers@xxxxxxxxxx>

[ Upstream commit 1e6f5dcc1b9ec9068f5d38331cec38b35498edf5 ]

The bpf_caps array is shorter without CAP_BPF, avoid out of bounds reads
if this isn't defined. Working around this avoids -Wno-array-bounds with
clang.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Reviewed-by: Tobias Klauser <tklauser@xxxxxxxxxx>
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20201027233646.3434896-1-irogers@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/bpf/bpftool/feature.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index a43a6f10b564c..359960a8f1def 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c
@@ -843,9 +843,14 @@ static int handle_perms(void)
else
p_err("missing %s%s%s%s%s%s%s%srequired for full feature probing; run as root or use 'unprivileged'",
capability_msg(bpf_caps, 0),
+#ifdef CAP_BPF
capability_msg(bpf_caps, 1),
capability_msg(bpf_caps, 2),
- capability_msg(bpf_caps, 3));
+ capability_msg(bpf_caps, 3)
+#else
+ "", "", "", "", "", ""
+#endif /* CAP_BPF */
+ );
goto exit_free;
}

--
2.27.0