[PATCH 5.17 0435/1126] bpftool: Fix error check when calling hashmap__new()

Greg Kroah-Hartman
2022-04-05T08:37:48Z

From: Mauricio Vásquez <mauricio@kinvolk.io>

[ Upstream commit 622a5b582cc27d3deedc38fcef68da2972e8e58d ]

hashmap__new() encodes errors with ERR_PTR(), hence it's not valid to
check the returned pointer against NULL and IS_ERR() has to be used
instead.

libbpf_get_error() can't be used in this case as hashmap__new() is not
part of the public libbpf API and it'll continue using ERR_PTR() after
libbpf 1.0.

Fixes: 8f184732b60b ("bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects")
Fixes: 2828d0d75b73 ("bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing")
Fixes: d6699f8e0f83 ("bpftool: Switch to libbpf's hashmap for PIDs/names references")
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220107152620.192327-2-mauricio@kinvolk.io
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/bpf/bpftool/btf.c | 2 +-
tools/bpf/bpftool/link.c | 3 ++-
tools/bpf/bpftool/map.c | 2 +-
tools/bpf/bpftool/pids.c | 3 ++-
tools/bpf/bpftool/prog.c | 2 +-
5 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 59833125ac0a..a2c665beda87 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -902,7 +902,7 @@ static int do_show(int argc, char **argv)
equal_fn_for_key_as_id, NULL);
btf_map_table = hashmap__new(hash_fn_for_key_as_id,
equal_fn_for_key_as_id, NULL);
- if (!btf_prog_table || !btf_map_table) {
+ if (IS_ERR(btf_prog_table) || IS_ERR(btf_map_table)) {
hashmap__free(btf_prog_table);
hashmap__free(btf_map_table);
if (fd >= 0)
diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c
index 2c258db0d352..97dec81950e5 100644
--- a/tools/bpf/bpftool/link.c
+++ b/tools/bpf/bpftool/link.c
@@ -2,6 +2,7 @@
/* Copyright (C) 2020 Facebook */

#include <errno.h>
+#include <linux/err.h>
#include <net/if.h>
#include <stdio.h>
#include <unistd.h>
@@ -306,7 +307,7 @@ static int do_show(int argc, char **argv)
if (show_pinned) {
link_table = hashmap__new(hash_fn_for_key_as_id,
equal_fn_for_key_as_id, NULL);
- if (!link_table) {
+ if (IS_ERR(link_table)) {
p_err("failed to create hashmap for pinned paths");
return -1;
}
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index cc530a229812..c66a3c979b7a 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -699,7 +699,7 @@ static int do_show(int argc, char **argv)
if (show_pinned) {
map_table = hashmap__new(hash_fn_for_key_as_id,
equal_fn_for_key_as_id, NULL);
- if (!map_table) {
+ if (IS_ERR(map_table)) {
p_err("failed to create hashmap for pinned paths");
return -1;
}
diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c
index 56b598eee043..7c384d10e95f 100644
--- a/tools/bpf/bpftool/pids.c
+++ b/tools/bpf/bpftool/pids.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2020 Facebook */
#include <errno.h>
+#include <linux/err.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
@@ -101,7 +102,7 @@ int build_obj_refs_table(struct hashmap **map, enum bpf_obj_type type)
libbpf_print_fn_t default_print;

*map = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL);
- if (!*map) {
+ if (IS_ERR(*map)) {
p_err("failed to create hashmap for PID references");
return -1;
}
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 2a21d50516bc..33ca834d5f51 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -641,7 +641,7 @@ static int do_show(int argc, char **argv)
if (show_pinned) {
prog_table = hashmap__new(hash_fn_for_key_as_id,
equal_fn_for_key_as_id, NULL);
- if (!prog_table) {
+ if (IS_ERR(prog_table)) {
p_err("failed to create hashmap for pinned paths");
return -1;
}
--
2.34.1