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 6DABB2E8DEC; Mon, 17 Aug 2026 15:13:08 +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=1786979589; cv=none; b=qj6y66QToC4+8dkCa8YdeGSxDtRcphQliaoDfvECF8bf1aRomAXedpcwIRRZQb4EwH4XHoDg9a0uGxfTSFIr4120DX1IAnmzLeH6++Zsdag6GufKSs34FVPArIyDJCP3oo45ZBO3QNHrK/5QkloCSohy70czp/GXEg16lPImliU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786979589; c=relaxed/simple; bh=LJ7O/z6TyAo1CVI6FuXqI5UfNq7Y8XWhqHzcaNvD6VQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uwzWX1L2VZpYxIdiXd5GVKSxZEbipm3hA3o0gNJydDqTUPZEDyKtE2rTd2hOg9o/X6fNsVjEyajesxf/mlqyYOaIx60QSOXORNxxDWpwv00a+A78t86PJE+zO31NCar81sPZ0P2yPbBI+5nQ3+nHhndZylcc8pWa2S0W9eD5qYA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OoihXDKI; 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="OoihXDKI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C52071F000E9; Mon, 17 Aug 2026 15:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786979588; bh=8lpbOj+7Zf+7GhYrFv25NMciys19MbQh/LVoQj0KOTE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OoihXDKIpio3d3oaW2zcfrNiDfg6nPWGOZYsTrGrp5wxXtHMUZeVS5ecqoEM/1jA2 r9iZOMSiIx27PMz+r8vHLr6KevBeXOtMDjPUHvtvfWAsR8lb1TGdRJ6a6CO1jh1o3C rwXzWeRtrqcppHcZm8QYOcYPesL0Dpqi8LclOVT8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sashiko , Steven Rostedt Subject: [PATCH 6.1 238/609] tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev Date: Mon, 17 Aug 2026 15:28:54 +0200 Message-ID: <20260817132552.040590446@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132543.039278408@linuxfoundation.org> References: <20260817132543.039278408@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt commit 144f29e85702234b23d2a62abf723e6a17eb5427 upstream. 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 Link: https://patch.msgid.link/20260721211143.36dbd559@gandalf.local.home Fixes: f984b51e0779 ("ftrace: add mmiotrace plugin") Reported-by: Sashiko Link: https://sashiko.dev/#/patchset/20260715143604.14481-1-gaikwad.dcg%40gmail.com Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_mmiotrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -146,7 +146,7 @@ static ssize_t mmio_read(struct trace_it goto print_out; } - if (!hiter) + if (!hiter || !hiter->dev) return 0; mmio_print_pcidev(s, hiter->dev);