From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 733D131327A; Fri, 7 Aug 2026 15:22:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786116176; cv=none; b=YX5w4ZynG9BDgn3h3DIwH8sv3xuc0sZ0PKtjwvujcgxgGwCb5N6n0uhvys1tb28mLGL1vocUmGrIRgi48eowChOUYdm1nC0ILU6ZW/ZTQFGTSO+rK2AmTQfBuTCajZizt7i14ytrrEgp6NMV1srAScqCntQzhLMA/yps3rKQ38Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786116176; c=relaxed/simple; bh=f48En3T1UnX8De6akLT1xdo+ZtEsFUjZlTdPBN73xuE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=V/OjrXh2uESVydiRG98NJp+L4w3O0Vp0mth+gYf815cJExU/15K1AWsLjqnrO+1T5gJ5XM433CYe9OFzwO5we4sFgCCjUMp7sWvfzT3cnxW7/5t9F4VqIOWXkGW+dwQfQOOZ/Nrs23kk7SxQuDIO+0NCn2syaUhHy/oLCxzVtLA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1S6be5P+; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1S6be5P+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFFE61F000E9; Fri, 7 Aug 2026 15:22:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786116175; bh=2CJC/HCr3wfhHoBKlvzI8o6dB3pO6yFCMo7X4xEIaVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1S6be5P+hOn6swFGmfqruqhrRuCYMq/9lCFwBZ0sZDg9JeaccQX83O4fH4WLe9IDi MQPxF95vSEivSjW/ZM8rR8mNMfxBXLSDgg5Ab8CNbOEoDkNNMT9AptkSvnM2hw5ffL YlDgCBXm31Lw/MUZnMiVoPp8kTI6hqPz5orm+sng= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Masami Hiramatsu (Google)" , Steven Rostedt Subject: [PATCH 6.6 139/261] tracing: Check return value of __register_event() in trace_module_add_events() Date: Fri, 7 Aug 2026 16:38:16 +0200 Message-ID: <20260807143418.364606098@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143415.358597922@linuxfoundation.org> References: <20260807143415.358597922@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masami Hiramatsu (Google) commit ac8719969e6c3c54e939834df812bc41f25453cf upstream. trace_module_add_events() ignores the return value of __register_event() and unconditionally calls __add_event_to_tracers() for each event. If __register_event() fails (for example, if event_init() fails), the trace_event_call is not added to ftrace_events list, but __add_event_to_tracers() still creates a trace_event_file pointing to it. If module loading subsequently fails and module memory is freed, tracing state retains a stale trace_event_call pointer in trace_event_file, leading to a use-after-free when tracefs or tracing subsystem operations are later executed. Fix this by checking the return value of __register_event() and only calling __add_event_to_tracers() if event registration succeeded. Fixes: ae63b31e4d0e ("tracing: Separate out trace events from global variables") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/178528487878.124250.14170824576025743236.stgit@devnote2 Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_events.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -3373,8 +3373,8 @@ static void trace_module_add_events(stru end = mod->trace_events + mod->num_trace_events; for_each_event(call, start, end) { - __register_event(*call, mod); - __add_event_to_tracers(*call); + if (!__register_event(*call, mod)) + __add_event_to_tracers(*call); } }