[PATCH 5.0 121/139] tools: bpftool: fix infinite loop in map create

Greg Kroah-Hartman
2019-05-23T19:24:47Z

[ Upstream commit 8694d8c1f82cccec9380e0d3720b84eee315dfb7 ]

"bpftool map create" has an infinite loop on "while (argc)". The error
case is missing.

Symptoms: when forgetting to type the keyword 'type' in front of 'hash':
$ sudo bpftool map create /sys/fs/bpf/dir/foobar hash key 8 value 8 entries 128
(infinite loop, taking all the CPU)
^C

After the patch:
$ sudo bpftool map create /sys/fs/bpf/dir/foobar hash key 8 value 8 entries 128
Error: unknown arg hash

Fixes: 0b592b5a01be ("tools: bpftool: add map create command")
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/bpf/bpftool/map.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 1ef1ee2280a28..227766d9f43b1 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -1111,6 +1111,9 @@ static int do_create(int argc, char **argv)
return -1;
}
NEXT_ARG();
+ } else {
+ p_err("unknown arg %s", *argv);
+ return -1;
}
}

--
2.20.1