linux-kernel - [PATCH] uprobes: fix incorrect lockdep condition in filter

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-next>] [day] [month] [year] [list]

Message-Id: <20260128-uprobe_rcu-v1-1-d41316763799@debian.org>
Date: Wed, 28 Jan 2026 01:58:38 -0800
From: Breno Leitao <leitao@...ian.org>
To: Masami Hiramatsu <mhiramat@...nel.org>, Oleg Nesterov <oleg@...hat.com>, 
 Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, 
 Arnaldo Carvalho de Melo <acme@...nel.org>, 
 Namhyung Kim <namhyung@...nel.org>, Mark Rutland <mark.rutland@....com>, 
 Alexander Shishkin <alexander.shishkin@...ux.intel.com>, 
 Jiri Olsa <jolsa@...nel.org>, Ian Rogers <irogers@...gle.com>, 
 Adrian Hunter <adrian.hunter@...el.com>, 
 James Clark <james.clark@...aro.org>, Andrii Nakryiko <andrii@...nel.org>
Cc: linux-kernel@...r.kernel.org, linux-trace-kernel@...r.kernel.org, 
 linux-perf-users@...r.kernel.org, kernel-team@...a.com, 
 stable@...r.kernel.org, Breno Leitao <leitao@...ian.org>
Subject: [PATCH] uprobes: fix incorrect lockdep condition in filter_chain()

The list_for_each_entry_rcu() in filter_chain() uses
rcu_read_lock_trace_held() as the lockdep condition, but the function
holds consumer_rwsem, not the RCU trace lock.

This gives me the following output when running with some locking debug
option enabled:

  kernel/events/uprobes.c:1141 RCU-list traversed in non-reader section!!
    filter_chain
    register_for_each_vma
    uprobe_unregister_nosync
    __probe_event_disable

Remove the incorrect lockdep condition since the rwsem provides
sufficient protection for the list traversal.

Cc: stable@...r.kernel.org
Fixes: 87195a1ee332a ("uprobes: switch to RCU Tasks Trace flavor for better performance")
Signed-off-by: Breno Leitao <leitao@...ian.org>
---
 kernel/events/uprobes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index d546d32390a81..726d13b375f3d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1138,7 +1138,7 @@ static bool filter_chain(struct uprobe *uprobe, struct mm_struct *mm)
 	bool ret = false;
 
 	down_read(&uprobe->consumer_rwsem);
-	list_for_each_entry_rcu(uc, &uprobe->consumers, cons_node, rcu_read_lock_trace_held()) {
+	list_for_each_entry(uc, &uprobe->consumers, cons_node) {
 		ret = consumer_filter(uc, mm);
 		if (ret)
 			break;

---
base-commit: 1f97d9dcf53649c41c33227b345a36902cbb08ad
change-id: 20260128-uprobe_rcu-e21867ab4c1b

Best regards,
--  
Breno Leitao <leitao@...ian.org>