From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Fri, 22 Dec 2017 11:36:06 -0800
Subject: tools: bpftool: protect against races with disappearing objects
Patch-mainline: v4.15-rc6
Git-commit: 8207c6dd4746c345b689684c4cd0ce00a18c7ef2
References: bsc#1109837
On program/map show we may get an ID of an object from GETNEXT,
but the object may disappear before we call GET_FD_BY_ID. If
that happens, ignore the object and continue.
Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
tools/bpf/bpftool/map.c | 2 ++
tools/bpf/bpftool/prog.c | 2 ++
2 files changed, 4 insertions(+)
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -528,6 +528,8 @@ static int do_show(int argc, char **argv
fd = bpf_map_get_fd_by_id(id);
if (fd < 0) {
+ if (errno == ENOENT)
+ continue;
p_err("can't get map by id (%u): %s",
id, strerror(errno));
break;
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -382,6 +382,8 @@ static int do_show(int argc, char **argv
fd = bpf_prog_get_fd_by_id(id);
if (fd < 0) {
+ if (errno == ENOENT)
+ continue;
p_err("can't get prog by id (%u): %s",
id, strerror(errno));
err = -1;