linux-kernel - [PATCHv8 bpf-next 02/13] bpf: Force uprobe bpf program to always return 0

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241018204109.713820-3-jolsa@kernel.org>
Date: Fri, 18 Oct 2024 22:40:58 +0200
From: Jiri Olsa <jolsa@...nel.org>
To: Oleg Nesterov <oleg@...hat.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Alexei Starovoitov <ast@...nel.org>,
	Daniel Borkmann <daniel@...earbox.net>,
	Andrii Nakryiko <andrii@...nel.org>
Cc: bpf@...r.kernel.org,
	Martin KaFai Lau <kafai@...com>,
	Song Liu <songliubraving@...com>,
	Yonghong Song <yhs@...com>,
	John Fastabend <john.fastabend@...il.com>,
	KP Singh <kpsingh@...omium.org>,
	Stanislav Fomichev <sdf@...ichev.me>,
	Hao Luo <haoluo@...gle.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	linux-kernel@...r.kernel.org,
	linux-trace-kernel@...r.kernel.org
Subject: [PATCHv8 bpf-next 02/13] bpf: Force uprobe bpf program to always return 0

As suggested by Andrii make uprobe multi bpf programs to always return 0,
so they can't force uprobe removal.

Keeping the int return type for uprobe_prog_run, because it will be used
in following session changes.

Fixes: 89ae89f53d20 ("bpf: Add multi uprobe link")
Suggested-by: Andrii Nakryiko <andrii@...nel.org>
Acked-by: Andrii Nakryiko <andrii@...nel.org>
Signed-off-by: Jiri Olsa <jolsa@...nel.org>
---
 kernel/trace/bpf_trace.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index fdab7ecd8dfa..3c1e5a561df4 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3209,7 +3209,6 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
 	struct bpf_prog *prog = link->link.prog;
 	bool sleepable = prog->sleepable;
 	struct bpf_run_ctx *old_run_ctx;
-	int err = 0;
 
 	if (link->task && !same_thread_group(current, link->task))
 		return 0;
@@ -3222,7 +3221,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
 	migrate_disable();
 
 	old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
-	err = bpf_prog_run(link->link.prog, regs);
+	bpf_prog_run(link->link.prog, regs);
 	bpf_reset_run_ctx(old_run_ctx);
 
 	migrate_enable();
@@ -3231,7 +3230,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
 		rcu_read_unlock_trace();
 	else
 		rcu_read_unlock();
-	return err;
+	return 0;
 }
 
 static bool
-- 
2.46.2