From patchwork Tue Feb 25 18:20:05 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13990583 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0A858C021B2 for ; Tue, 25 Feb 2025 19:31:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:Subject:Cc:To:From:Date:Message-ID:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: List-Owner; bh=VXFiOteoRndUMjDIfghZJo/kzGnODUzHU+WRQHnHsyg=; b=vrHul/Qcuu3vXl +XYeArPU6Sz+/VO+PEQN6HpqWVv1yz8YVAtyxYaJ2Bv5fan2y09Ghz85G2Ah2dlg2iA10SA6rJoAV KLOv/9/7n0o/bJIIVCN9Ld76O2hh2Gpa1ESWNiQBLuuNgeunEzbf6cgPCROXhD2RAjoF9BBWffvwN YpF89oMmNKb78vR85YdZvieGSsJX165AXl0TgjbyzGk/InEMEi8S1P+0hC09Fg92lJcGcYcziMBbW TM5mqZzSmAzCM9VRQPooWq9B541QdRsXUxwa6xX5XL+OV3m60trIw2gxsNQqZ1qdQamJpB/s3VUgS tE/5G8AQPwrMJ0EOUJTA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tn0eY-000000019C9-1qdd; Tue, 25 Feb 2025 19:31:38 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tmzXU-00000000tU7-1uXT for linux-arm-kernel@lists.infradead.org; Tue, 25 Feb 2025 18:20:16 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id C3C49612E9; Tue, 25 Feb 2025 18:20:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63DA3C4CEDD; Tue, 25 Feb 2025 18:20:15 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98) (envelope-from ) id 1tmzY6-000000095Xv-1qYA; Tue, 25 Feb 2025 13:20:54 -0500 Message-ID: <20250225182054.290128736@goodmis.org> User-Agent: quilt/0.68 Date: Tue, 25 Feb 2025 13:20:05 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Masahiro Yamada , Catalin Marinas , Will Deacon , Nathan Chancellor , "Arnd Bergmann" , Mark Brown Subject: [PATCH 1/4] ftrace: Test mcount_loc addr before calling ftrace_call_addr() References: <20250225182004.473875894@goodmis.org> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Steven Rostedt The addresses in the mcount_loc can be zeroed and then moved by KASLR making them invalid addresses. ftrace_call_addr() for ARM 64 expects a valid address to kernel text. If the addr read from the mcount_loc section is invalid, it must not call ftrace_call_addr(). Move the addr check before calling ftrace_call_addr() in ftrace_process_locs(). Fixes: ef378c3b8233 ("scripts/sorttable: Zero out weak functions in mcount_loc table") Reported-by: Nathan Chancellor Reported-by: "Arnd Bergmann" Tested-by: Nathan Chancellor Closes: https://lore.kernel.org/all/20250225025631.GA271248@ax162/ Closes: https://lore.kernel.org/all/91523154-072b-437b-bbdc-0b70e9783fd0@app.fastmail.com/ Signed-off-by: Steven Rostedt (Google) --- kernel/trace/ftrace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 27c8def2139d..183f72cf15ed 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7063,7 +7063,9 @@ static int ftrace_process_locs(struct module *mod, pg = start_pg; while (p < end) { unsigned long end_offset; - addr = ftrace_call_adjust(*p++); + + addr = *p++; + /* * Some architecture linkers will pad between * the different mcount_loc sections of different @@ -7075,6 +7077,8 @@ static int ftrace_process_locs(struct module *mod, continue; } + addr = ftrace_call_adjust(addr); + end_offset = (pg->index+1) * sizeof(pg->records[0]); if (end_offset > PAGE_SIZE << pg->order) { /* We should have allocated enough */