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 093A2422554; Thu, 16 Jul 2026 13:36:21 +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=1784208983; cv=none; b=nSUFMKhLJVAeanzam9lK34eAiTfDtxE+dmQNaKkDHlVvR1NPnyRM3gnfu5q/lIcsydz16KlCMXPL6IgqGo47uIwVmZiV18nP2Ipk1t9RpUZvT2+6k+Sn/WUF54+b/ZmQnEWbpvJBYMhgjYJnuCeEcQftjoSj70Q0RW6SWFdAmDw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784208983; c=relaxed/simple; bh=Ld1/SBefUAGbH+rdU0vmWWhp1FoPAyvav7Xbl9IC7WA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XGQKH/a+b+k8K8i8DZfKzEd+7f+3KtK8HvGty+K1KDm9ZT6l8A8N/hLwaVihRH63Oc6rck9jAdIAn5znTn1CVxLA7LYv72uCClPgu/0QZgQGU1bCZHxuAII3IarIEDMRa5+wBZIsriQ7/UsnEP6s9q9qa5ljITN6X7o6FK/EDjQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=S6haeY2A; 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="S6haeY2A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31F181F000E9; Thu, 16 Jul 2026 13:36:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784208981; bh=aktzgeKuFR3GOTdThBL+qs/pSatd+oFyZQZ6TTd2GzA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=S6haeY2AEfvMEcv2Xh3DSYCYi7dDy31bjp+ESGB11Tt7gEBMz0ieYjeJ/Ew6XRIOC rmRXHP2+dnud84lc4O3qtcOn7bD/ybMV08E3zzkrfB7Cfd78saeJ+AFcfxGhHTYnQv rLuWNCAUqwAIMDBHIFNR0oikhbE7QZcDKWonpBE4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Rafael J. Wysocki" , Dave Jiang Subject: [PATCH 7.1 013/518] ACPI: NFIT: core: Fix acpi_nfit_init() error cleanup Date: Thu, 16 Jul 2026 15:24:41 +0200 Message-ID: <20260716133048.065318297@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260716133047.772246337@linuxfoundation.org> References: <20260716133047.772246337@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 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rafael J. Wysocki commit 38bf27511ef41bffebd157ec3eba41fc89ba59cd upstream. If acpi_nfit_init() fails after adding the acpi_desc object to the acpi_descs list, that object is never removed from that list because the acpi_nfit_shutdown() devm action is not added for the NFIT device in that case. Next, the acpi_nfit_init() failure causes acpi_nfit_probe() to fail, the acpi_desc object is freed, and a dangling pointer is left behind in the acpi_descs. Any subsequent ACPI Machine Check Exception will trigger nfit_handle_mce() which iterates over acpi_descs and so a use-after-free will occur. Moreover, if acpi_nfit_probe() returns 0 after installing a notify handler for the NFIT device and without allocating the acpi_desc object and setting the NFIT device's driver data pointer, the acpi_desc object will be allocated by acpi_nfit_update_notify() and acpi_nfit_init() will be called to initialize it. Regardless of whether or not acpi_nfit_init() fails in that case, the acpi_nfit_shutdown() devm action is not added for the NFIT device and acpi_desc is never removed from the acpi_descs list. If the acpi_desc object is freed subsequently on driver removal, any subsequent ACPI MCE will lead to a use-after-free like in the previous case. To address the first issue mentioned above, make acpi_nfit_probe() call acpi_nfit_shutdown() directly on acpi_nfit_init() failures and to address the other one, add a remove callback to the driver and make it call acpi_nfit_shutdown(). Also, since it is now possible to pass NULL to acpi_nfit_shutdown() or the acpi_desc object passed to it may not have been initialized, add checks against NULL for acpi_desc and its nvdimm_bus field to that function and make acpi_nfit_unregister() clear the latter after unregistering the NVDIMM bus. Fixes: a61fe6f7902e ("nfit, tools/testing/nvdimm: unify common init for acpi_nfit_desc") Fixes: fbabd829fe76 ("acpi, nfit: fix module unload vs workqueue shutdown race") Signed-off-by: Rafael J. Wysocki Cc: All applicable Reviewed-by: Dave Jiang Link: https://patch.msgid.link/1963615.tdWV9SEqCh@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/nfit/core.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -3069,6 +3069,8 @@ static void acpi_nfit_unregister(void *d struct acpi_nfit_desc *acpi_desc = data; nvdimm_bus_unregister(acpi_desc->nvdimm_bus); + /* The nvdimm_bus object may have been freed, so clear the pointer. */ + acpi_desc->nvdimm_bus = NULL; } int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, void *data, acpi_size sz) @@ -3309,7 +3311,10 @@ static void acpi_nfit_remove_notify_hand void acpi_nfit_shutdown(void *data) { struct acpi_nfit_desc *acpi_desc = data; - struct device *bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus); + struct device *bus_dev; + + if (!acpi_desc || !acpi_desc->nvdimm_bus) + return; /* * Destruct under acpi_desc_lock so that nfit_handle_mce does not @@ -3324,6 +3329,7 @@ void acpi_nfit_shutdown(void *data) mutex_unlock(&acpi_desc->init_mutex); cancel_delayed_work_sync(&acpi_desc->dwork); + bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus); /* * Bounce the nvdimm bus lock to make sure any in-flight * acpi_nfit_ars_rescan() submissions have had a chance to @@ -3406,9 +3412,14 @@ static int acpi_nfit_probe(struct platfo sz - sizeof(struct acpi_table_nfit)); if (rc) - return rc; + acpi_nfit_shutdown(acpi_desc); - return devm_add_action_or_reset(dev, acpi_nfit_shutdown, acpi_desc); + return rc; +} + +static void acpi_nfit_remove(struct platform_device *pdev) +{ + acpi_nfit_shutdown(platform_get_drvdata(pdev)); } static void acpi_nfit_update_notify(struct device *dev, acpi_handle handle) @@ -3492,6 +3503,7 @@ MODULE_DEVICE_TABLE(acpi, acpi_nfit_ids) static struct platform_driver acpi_nfit_driver = { .probe = acpi_nfit_probe, + .remove = acpi_nfit_remove, .driver = { .name = "acpi-nfit", .acpi_match_table = acpi_nfit_ids,