From nobody Sat Jul 25 00:03:08 2026 Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) (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 A379C282F18; Wed, 22 Jul 2026 01:11:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.16 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784682695; cv=none; b=TOMCXcSPImcR2stO23ZDaf8jc4FUbyz6MTgkE7Z80J81H2JFR5KbLrIAfzAnq8Yo/hWix5gvohaWL/+mDByl8sHnafF65tq5xK8WjznsWnYEQWpksT3lDqvGk1wsHz2slrFfKIS0gLvlgULl3JDIdxBU8jUd3P470+zs8qz9h40= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784682695; c=relaxed/simple; bh=S0IC7Lhl0SxfXzJCkSeuB4x1sy5XgyUtsk1ascIIJFc=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=CUI1/y803wQjSyZEYIdZFm19rm0jKo9DrkxSQvsnBpM8vkp3xDRE5RBaH+vKhF/8NH53gEkHqpcVdLJ7lIEF6tNDuk1bYApHyoL8FmbsKBcs6bwbGhZR2eQO90Kqe9paH5evb4W9UkdsWaDmD12CeDNXQKuMFguywxgFNBePf0M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf14.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 66FF0C0152; Wed, 22 Jul 2026 01:11:30 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf14.hostedemail.com (Postfix) with ESMTPA id DE80233; Wed, 22 Jul 2026 01:11:28 +0000 (UTC) Date: Tue, 21 Jul 2026 21:11:43 -0400 From: Steven Rostedt To: LKML , Linux Trace Kernel Cc: Masami Hiramatsu , Mathieu Desnoyers Subject: [PATCH] tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev Message-ID: <20260721211143.36dbd559@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Stat-Signature: jhz8iig39uo4uiajjz8mx8th4ni8r5ot X-Rspamd-Server: rspamout06 X-Rspamd-Queue-Id: DE80233 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18MD1yTveXFTETYCXfp2FVSeraat7QQjfc= X-HE-Tag: 1784682688-914176 X-HE-Meta: U2FsdGVkX1+Ybu8zFG8uSidq8BZXboN8tGTrSqfquer35bJxb6Qz2qy1aOhoKwHa2pFXJ676YFBL6pSTznUd5ViKuc+YHh25/P5I5yW2FcmnIdjrE8UICj8dtZG9LrsJ3ntTlyKUcbwMc+fGmcLxQEmmEHY7pvi1UYwWobX2Q/GRUvxcxmBWheGdIHiwxjFFtWctG7CWqKjIuqT0SIVSPUQFze5CzuW8071/8RzQlz6eIX4IjlOjcm17eZ1I9Rs7JDnoCmsMvOvJcJpF2Ywu6II1TOC9PehtZwK7qGu8ENcZXFI/gVo3KS8tP7zCIRhUtmliZs4Tf71pEkG5/5W4hA2/yHKHNrCMdFOUMe4otFSU7AHidU64Rza4O/40AyHCa9f2xQCm3uHVk9LROmNcXcvPsU5z0IHuGVHIXSSKdcGZ5PqbBfRAU0rphCrc3iFp/t+DQN/4U5B6//sh6LaBDki7uU1v72LL+pG8toQ82Vk= Content-Type: text/plain; charset="utf-8" From: Steven Rostedt If the mmio_pipe_open() fails to find a PCI device, the hiter->dev will be assigned to NULL. The mmiotrace read() function dereferences the hiter->dev if hiter exists. Change the test of the read to not only check hiter being NULL, but also the hiter->dev before dereferencing it. Cc: stable@vger.kernel.org Fixes: f984b51e0779 ("ftrace: add mmiotrace plugin") Reported-by: Sashiko Link: https://sashiko.dev/#/patchset/20260715143604.14481-1-gaikwad.dcg%40g= mail.com Signed-off-by: Steven Rostedt --- kernel/trace/trace_mmiotrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 20812e7f911f..b88b8d9923ad 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -145,7 +145,7 @@ static ssize_t mmio_read(struct trace_iterator *iter, s= truct file *filp, goto print_out; } =20 - if (!hiter) + if (!hiter || !hiter->dev) return 0; =20 mmio_print_pcidev(s, hiter->dev); --=20 2.53.0