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 93D4D3290C7; Fri, 7 Aug 2026 14:47:09 +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=1786114032; cv=none; b=bRtYtRGdqd1+wpBqP+VqKJEe/fdxiPgDb97cTc6BuqemoOwtHhaxBe+Q9W1Gk/WhX70kTmqQ3dDuTuuaBVqaOivzwjDT/TNaVliNsSXSHL3do/PCNwAfgzVEZpnH/BWBacM08A5Izb1T6JvlILj2ZvuoCzgK+ZnfSm9/yVBPfq0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114032; c=relaxed/simple; bh=zssasMBzQYxaIHYg9zPtwx8nx61ZqWUZfnojSv0pJDQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sgG1aKvn3Y3ckHebHnys90muBS/FOANW57TEM9CVR0oWeYzOoTCcGUpA4kpLoWzBKkThRzMvnl2J7gd4zqLscEpVaqx0VIgo+UIaSLYf9V4YPJ8LLKBwyggaOf6ww3BUZYNR9GsyQpm4N1kUyv77jS/qBir9v0MgKCL8I1pUDj4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wtZKIA/E; 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="wtZKIA/E" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F15231F000E9; Fri, 7 Aug 2026 14:47:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786114028; bh=23wbqT2c66UBI+YmShP38zlIT3IAqHWaG2WpkrrFv08=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=wtZKIA/E1VAYa8jNOk8PWCNPOF123imO7X+REUthoXZWhCEOFSzdCivHsgyfwa5FP pczfnTMrnkfmzOoWLjQZKs9nAKTAw+TNaW6IwHGFQS8YFqlha7WQ9twdGzUpnWjzCE dVgtcxCdVYC7f5w2qCx38jmGQup5O/CbhGvLS+gk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Masami Hiramatsu (Google)" , Steven Rostedt , Sasha Levin Subject: [PATCH 6.12 117/337] tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions Date: Fri, 7 Aug 2026 16:35:20 +0200 Message-ID: <20260807143421.067366429@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143418.516897842@linuxfoundation.org> References: <20260807143418.516897842@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masami Hiramatsu (Google) [ Upstream commit 12b80cdbc54cf615b4717a4e8180063408091ea2 ] mmio_trace_rw() and mmio_trace_mapping() retrieve mmio_trace_array into tr and pass it to __trace_mmiotrace_rw() and __trace_mmiotrace_map(). If these functions are invoked while mmio_trace_array is NULL (e.g. before initialization or after disabled), accessing tr->array_buffer.buffer will result in a NULL pointer dereference crash. Fix this by adding an explicit NULL check for tr at the beginning of __trace_mmiotrace_rw() and __trace_mmiotrace_map(). Link: https://patch.msgid.link/178524300062.56416.8362487250709962380.stgit@devnote2 Fixes: f984b51e0779 ("ftrace: add mmiotrace plugin") Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt Signed-off-by: Sasha Levin --- kernel/trace/trace_mmiotrace.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 6b964471265e1..251ed7051e409 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -295,11 +295,15 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data, struct mmiotrace_rw *rw) { - struct trace_buffer *buffer = tr->array_buffer.buffer; + struct trace_buffer *buffer; struct ring_buffer_event *event; struct trace_mmiotrace_rw *entry; unsigned int trace_ctx; + if (!tr) + return; + + buffer = tr->array_buffer.buffer; trace_ctx = tracing_gen_ctx_flags(0); event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW, sizeof(*entry), trace_ctx); @@ -324,11 +328,15 @@ static void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data, struct mmiotrace_map *map) { - struct trace_buffer *buffer = tr->array_buffer.buffer; + struct trace_buffer *buffer; struct ring_buffer_event *event; struct trace_mmiotrace_map *entry; unsigned int trace_ctx; + if (!tr) + return; + + buffer = tr->array_buffer.buffer; trace_ctx = tracing_gen_ctx_flags(0); event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP, sizeof(*entry), trace_ctx); -- 2.53.0