From nobody Tue Dec 2 02:33:07 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 EE5F73702F4 for ; Tue, 18 Nov 2025 21:21:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763500887; cv=none; b=B/rx7wNV7BQLJTinfqj0rvzM3tiC1JrTzcaSIs3LNSCCGP5XzfvvgK3wa+fcpQ2kk4mE/mnqoThwSV58gKkv62t6ogIyK8D9DBOSd2n/HXyhR6FJOxOXtxfuOfGpk8kM9xnkza9ZqWqT8nkLJLo7PsYfCgpEEeaWwTmXd8YBhEM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763500887; c=relaxed/simple; bh=R+Iz4uKsSqDDLX8bIJmIsKBIRdHvXEVm7lAEyY21kRw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DOL7gcGnLNBBKbclscbV5F7LVRbyXrrwx4k5Zrwx741gROu0lBgVt+f4o4u68YGj9DZgnoorPm48w/9oPaUzcBEzk0ot7mIOtjM05Kr0mUMIslA/QuTBbOjNniA4Yq6Jh+yAR/WbVisbc2GozQxLxTHBfZZ6t4KbjtfURrJC1n0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=IT1KgqF0; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="IT1KgqF0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1763500883; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wRh+YFtUXZHccU89UWSvkWRaWI80gowASgRgcTaihiw=; b=IT1KgqF07ct6eJcWweAYlKLqK2eIjSJ9nqq/b8QQ07ghjdO5XD7peZgTIU8r8JDTSAXA4F EMSep9EHHdCfHEQeo92dq5CkrzgW8/j5OdkoyIMeOAbt6DcHR8mU7lypw2CoFp7tPhkEK7 ecmyOFqUaWVjBwzYjf2eFiB3PO4QYJA= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-344--m8cPmM-Px2uCxv4w8oLvA-1; Tue, 18 Nov 2025 16:21:22 -0500 X-MC-Unique: -m8cPmM-Px2uCxv4w8oLvA-1 X-Mimecast-MFC-AGG-ID: -m8cPmM-Px2uCxv4w8oLvA_1763500881 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 79356180035F; Tue, 18 Nov 2025 21:21:21 +0000 (UTC) Received: from darcari-thinkpadt14sgen1.bos.com (unknown [10.22.64.106]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 42A151800451; Tue, 18 Nov 2025 21:21:20 +0000 (UTC) From: David Arcari To: alexander.shishkin@linux.intel.com Cc: linux-kernel@vger.kernel.org, jerry.hoemann@hpe.com, David Arcari Subject: [PATCH v2] intel_th: core: fix null pointer dereference in intel_th_irq Date: Tue, 18 Nov 2025 16:21:06 -0500 Message-ID: <20251118212106.541728-1-darcari@redhat.com> In-Reply-To: <20250825174554.925679-1-darcari@redhat.com> References: <20250825174554.925679-1-darcari@redhat.com> 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-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Content-Type: text/plain; charset="utf-8" In certain cases intel_th_irq can reference a null entry in the th->thdev array. This results in the splat shown below. The problem is that intel_th_output_enable() can modify the thdev[] array at the same time intel_th_irq is referencing the same array. This can be fixed by disabling interrupts during the call to intel_th_output_enable(). BUG: kernel NULL pointer dereference, address: 0000000000000304 Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:intel_th_irq+0x26/0x70 [intel_th] Call Trace: ? show_trace_log_lvl+0x1b0/0x2f0 ? show_trace_log_lvl+0x1b0/0x2f0 ? __handle_irq_event_percpu+0x4a/0x180 ? __die_body.cold+0x8/0x12 ? page_fault_oops+0x148/0x160 ? exc_page_fault+0x73/0x160 ? asm_exc_page_fault+0x26/0x30 ? intel_th_irq+0x26/0x70 [intel_th] __handle_irq_event_percpu+0x4a/0x180 handle_irq_event+0x38/0x80 handle_fasteoi_irq+0x78/0x200 __common_interrupt+0x3e/0x90 common_interrupt+0x80/0xa0 Fixes: a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") Cc: Alexander Shishkin Cc: linux-kernel@vger.kernel.org Cc: Jerry Hoemann Signed-off-by: David Arcari --- v2: switched to use scoped based lock guard functionality drivers/hwtracing/intel_th/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th= /core.c index 47d9e6c3bac0..7b7dcc651efe 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -717,6 +717,8 @@ int intel_th_output_enable(struct intel_th *th, unsigne= d int otype) struct intel_th_device *thdev; int src =3D 0, dst =3D 0; =20 + guard(disable_irq)(&th->irq); + for (src =3D 0, dst =3D 0; dst <=3D th->num_thdevs; src++, dst++) { for (; src < ARRAY_SIZE(intel_th_subdevices); src++) { if (intel_th_subdevices[src].type !=3D INTEL_TH_OUTPUT) --=20 2.51.0