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 73A4E4749FC; Fri, 24 Jul 2026 23:18:30 +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=1784935111; cv=none; b=SacgQbVAuxXvnse224KfQG7gjNitSblhk030lsAbkZYHmkJcWBGvWLqLhLQawBulHafSiF7p/SHoxGG7Tca882L/KY96/yHsc6toRC+3s2okaLCHxn2G5FjosBnanL/6GYyYgExU7ZOAtBfKNw7CPD4IuXGWPvEa2qENiMK2UIs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784935111; c=relaxed/simple; bh=5vXE0PhSNG6DD41aTyCfzaKSlB/mB2jHbx/Ufjc5BNY=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=rIhDm5CW97qGva+futo1ePbVac2x/o6FUWiRN+N4J483DjmiE4jJa8kVYYHbrSocWlB0vrahaN/O6uADH7qMu+33kHpjiYKN7bdSI+BUpOW8NmpNHk7LC6YGOpJ6PWP0l/A+T6iKxK+1B91Y2sm7zcQL2m5GctsAEqCvXO8wO1Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EVdIC0BA; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EVdIC0BA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 588801F00A3E; Fri, 24 Jul 2026 23:18:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784935110; bh=FhZ/5Pv9AeXrXf4KLh5hTBTtjmg9+0RNyc9HRq1oARg=; h=Date:From:To:Cc:Subject:References; b=EVdIC0BATVMJcZMc0OsA7IS2T6mvDAmoDitSiWrcgPOGpyM+rLXbJTc415z/K4FFU sdMGe7vWldFAY8OeXV6VJJtxcNauUK/PIdT766FKchcnD94I+vjRbG1oFwS/0xx0FS ZgkLZ5SB+6/Om9gSD7wSIQBCisNaeUnA4DLEShwNqidx4Z82t6EIBvBTeoQQ/AwN5x w6Ak1mBvnXCquoh55FpXlBNjgE2ggOaGOlxSdUrCDnM3DQjlFR5o0K7Vo0xJGSIih+ x9g+zq3r5gb7KW2vJb3HGFrBuYo5Nu9hkWoRq/D8h5+yWwXw6LPHPx7h5TBfMMlZg8 ZF0nlToBj82bw== Received: from rostedt by gandalf with local (Exim 4.99.4) (envelope-from ) id 1wnPAO-000000046sy-0yEk; Fri, 24 Jul 2026 19:18:56 -0400 Message-ID: <20260724231856.091344694@kernel.org> User-Agent: quilt/0.69 Date: Fri, 24 Jul 2026 19:18:44 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , stable@vger.kernel.org, Sashiko Subject: [for-linus][PATCH 4/9] tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev References: <20260724231840.483353969@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 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 --- 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, struct file *filp, goto print_out; } - if (!hiter) + if (!hiter || !hiter->dev) return 0; mmio_print_pcidev(s, hiter->dev); -- 2.53.0