[PATCH 5.15 101/279] perf bpf: Avoid memory leak from perf_env__insert_btf()
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-11-24 13:51:28
Also in:
bpf, lkml, netdev
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
From: Ian Rogers <irogers@google.com>
[ Upstream commit 4924b1f7c46711762fd0e65c135ccfbcfd6ded1f ]
perf_env__insert_btf() doesn't insert if a duplicate BTF id is
encountered and this causes a memory leak. Modify the function to return
a success/error value and then free the memory if insertion didn't
happen.
v2. Adds a return -1 when the insertion error occurs in
perf_env__fetch_btf. This doesn't affect anything as the result is
never checked.
Fixes: 3792cb2ff43b1b19 ("perf bpf: Save BTF in a rbtree in perf_env")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <redacted>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <redacted>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <redacted>
Cc: Stephane Eranian <redacted>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yonghong Song <redacted>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211112074525.121633-1-irogers@google.com (local)
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/util/bpf-event.c | 6 +++++-
tools/perf/util/env.c | 5 ++++-
tools/perf/util/env.h | 2 +-
3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index a410b3968b3af..16ad0e6e9e9c5 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c@@ -120,7 +120,11 @@ static int perf_env__fetch_btf(struct perf_env *env, node->data_size = data_size; memcpy(node->data, data, data_size); - perf_env__insert_btf(env, node); + if (!perf_env__insert_btf(env, node)) { + /* Insertion failed because of a duplicate. */ + free(node); + return -1; + } return 0; }
diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index cf773f0dec384..5b24eb010336c 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c@@ -74,12 +74,13 @@ out: return node; } -void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) +bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) { struct rb_node *parent = NULL; __u32 btf_id = btf_node->id; struct btf_node *node; struct rb_node **p; + bool ret = true; down_write(&env->bpf_progs.lock); p = &env->bpf_progs.btfs.rb_node;
@@ -93,6 +94,7 @@ void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) p = &(*p)->rb_right; } else { pr_debug("duplicated btf %u\n", btf_id); + ret = false; goto out; } }
@@ -102,6 +104,7 @@ void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) env->bpf_progs.btfs_cnt++; out: up_write(&env->bpf_progs.lock); + return ret; } struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index 1383876f72b37..163e5ec503a26 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h@@ -167,7 +167,7 @@ void perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node); struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, __u32 prog_id); -void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node); +bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node); struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id); int perf_env__numa_node(struct perf_env *env, int cpu);
--
2.33.0