diff mbox series

[v2,1/9] tracing/probes: Fix to add NULL check for BTF APIs

Message ID	168960740754.34107.12202350138610653557.stgit@devnote2
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> To: linux-trace-kernel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>, mhiramat@kernel.org, Martin KaFai Lau <martin.lau@linux.dev>, bpf@vger.kernel.org, Sven Schnelle <svens@linux.ibm.com>, Alexei Starovoitov <ast@kernel.org> Subject: [PATCH v2 1/9] tracing/probes: Fix to add NULL check for BTF APIs Date: Tue, 18 Jul 2023 00:23:27 +0900 Message-Id: <168960740754.34107.12202350138610653557.stgit@devnote2> In-Reply-To: <168960739768.34107.15145201749042174448.stgit@devnote2> References: <168960739768.34107.15145201749042174448.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk
Series	tracing: Improbe BTF support on probe events \| [v2,0/9] tracing: Improbe BTF support on probe events [v2,1/9] tracing/probes: Fix to add NULL check for BTF APIs [v2,2/9] bpf/btf: tracing: Move finding func-proto API and getting func-param API to BTF [v2,3/9] bpf/btf: Add a function to search a member of a struct/union [v2,4/9] tracing/probes: Support BTF based data structure field access [v2,5/9] tracing/probes: Support BTF field access from $retval [v2,6/9] tracing/probes: Add string type check with BTF [v2,7/9] tracing/fprobe-event: Assume fprobe is a return event by $retval [v2,8/9] selftests/ftrace: Add BTF fields access testcases [v2,9/9] Documentation: tracing: Update fprobe event example with BTF field

Commit Message

Masami Hiramatsu (Google) July 17, 2023, 3:23 p.m. UTC

  From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Since find_btf_func_param() abd btf_type_by_id() can return NULL,
the caller must check the return value correctly.

Fixes: b576e09701c7 ("tracing/probes: Support function parameters if BTF is available")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 kernel/trace/trace_probe.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff mbox series

Patch

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index b2b726bea1f9..c68a72707852 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -386,12 +386,12 @@  static const struct btf_type *find_btf_func_proto(const char *funcname)
 
 	/* Get BTF_KIND_FUNC type */
 	t = btf_type_by_id(btf, id);
-	if (!btf_type_is_func(t))
+	if (!t || !btf_type_is_func(t))
 		return ERR_PTR(-ENOENT);
 
 	/* The type of BTF_KIND_FUNC is BTF_KIND_FUNC_PROTO */
 	t = btf_type_by_id(btf, t->type);
-	if (!btf_type_is_func_proto(t))
+	if (!t || !btf_type_is_func_proto(t))
 		return ERR_PTR(-ENOENT);
 
 	return t;
@@ -443,7 +443,7 @@  static int parse_btf_arg(const char *varname, struct fetch_insn *code,
 	if (!ctx->params) {
 		params = find_btf_func_param(ctx->funcname, &ctx->nr_params,
 					     ctx->flags & TPARG_FL_TPOINT);
-		if (IS_ERR(params)) {
+		if (IS_ERR_OR_NULL(params)) {
 			trace_probe_log_err(ctx->offset, NO_BTF_ENTRY);
 			return PTR_ERR(params);
 		}
@@ -1273,7 +1273,7 @@  const char **traceprobe_expand_meta_args(int argc, const char *argv[],
 
 	params = find_btf_func_param(ctx->funcname, &nr_params,
 				     ctx->flags & TPARG_FL_TPOINT);
-	if (IS_ERR(params)) {
+	if (IS_ERR_OR_NULL(params)) {
 		if (args_idx != -1) {
 			/* $arg* requires BTF info */
 			trace_probe_log_err(0, NOSUP_BTFARG);