From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from layka.disroot.org (layka.disroot.org [178.21.23.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4045498927; Fri, 11 Sep 2026 15:57:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.21.23.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789142232; cv=none; b=Ylmew8arCcJ8TxuPPvRzx4XZJYgMGCnlMSfJDplZyQ6FMmkmf4RbpBz7BPFuSEp2d9em/DOt6Q+zY2Ej3a+vLIMz458xIUFZp67GE1HYOebiLFg1eZeu5UPfWY5vUHVbtuLsxRU/oR9wGGV5MgGcknPlBp+YI73SOWRoBU80UGA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789142232; c=relaxed/simple; bh=YsIahrjsMCLx8Vmej19Tp6nrCVLGETYWzUEZiMxepNU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=n6Yt/OfNAohJhu7Ba9xQ4QQA0NmDZ4ndb5KVpYNbOSrt+6D71cyB6YQSlBf+ik3vNgVDG6z1PRbOYTu59BZGpQ9IGBjgUYqS8nmWgbArbamvgPBPTTIsVpoZLmQxtJODTzCbqdo1I/7BFuQV7YUADvSXwtEACGIFgO6AdOMY3f0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org; spf=pass smtp.mailfrom=disroot.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b=N9G2QCoq; arc=none smtp.client-ip=178.21.23.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=disroot.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b="N9G2QCoq" Received: from mail01.layka.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id 8C29480F31; Fri, 11 Sep 2026 17:57:02 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 7CclxIKH0vMb; Fri, 11 Sep 2026 17:57:01 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1789142221; bh=YsIahrjsMCLx8Vmej19Tp6nrCVLGETYWzUEZiMxepNU=; h=From:To:Cc:Subject:Date; b=N9G2QCoq0+Pgl5QtPP9JYVHa0974oXqcLacRQ9116+3oEulyC/UOcMFEcWZTqiR2A z2Dyd1WuvoV6Y5/B+IlXczqljy//UEBq4jrbB9MSFiAagQOTp7s8FxD9lOOf83k4RC stN/UaLerY/FMTCkxrcfx48FQj0rPqGs3Zin51aBVgcrBxPfqBeywqFlldSsRDu5ew zpwmtQSAIAKVd4nvQ6LLVjqxHWdrNJ5NXt4KUpvXB00GrFGsMCRl/7+jkToN1RQiPt OQkdZFGu4H4mfzjNq9YqoozI4XqX7tCrNGZPTQBZvAPMJZ/6vRLuusfqVX14xHXhqj 5fUpwlL0Acqvw== From: =?UTF-8?q?Ali=20Ahmet=20Memi=C5=9F?= To: rostedt@goodmis.org Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, agordeev@linux.ibm.com, linux-s390@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH] tracing: Don't dereference trace_event_file in deferred trigger free Date: Fri, 11 Sep 2026 18:56:47 +0300 Message-ID: <20260911155650.354844-1-aliamemis@disroot.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The enable_event trigger defers trace_event_put_ref() to the trigger free kthread, but the trace_event_file can already be freed when the instance is removed. Keep the trace_event_call directly in enable_trigger_data so the deferred free does not access the freed trace_event_file. Fixes: e091351b3881 ("tracing: Delay module ref count for "enable_event" trigger") Reported-by: Alexander Gordeev Closes: https://lore.kernel.org/all/20260828134340.2501683A24-agordeev@linux.ibm.com/ Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memiş --- kernel/trace/trace.h | 1 + kernel/trace/trace_events_trigger.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 74a7a50d1e78..0de92b4575e5 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1952,6 +1952,7 @@ struct event_trigger_data { struct enable_trigger_data { struct trace_event_file *file; + struct trace_event_call *call; bool enable; bool hist; }; diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index 149300cc5e8a..4d2fde996c0f 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1728,7 +1728,8 @@ static void enable_trigger_private_data_free(struct event_trigger_data *data) { struct enable_trigger_data *enable_data = data->private_data; - trace_event_put_ref(enable_data->file->event_call); + /* The file may already be freed here, only the call is kept alive */ + trace_event_put_ref(enable_data->call); kfree(enable_data); } @@ -1801,6 +1802,7 @@ int event_enable_trigger_parse(struct event_command *cmd_ops, enable_data->hist = hist; enable_data->enable = enable; enable_data->file = event_enable_file; + enable_data->call = event_enable_file->event_call; trigger_data = trigger_data_alloc(cmd_ops, cmd, param, enable_data); if (!trigger_data) -- 2.55.0