From patchwork Tue Aug 15 13:15:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 713920 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0738C04FE0 for ; Tue, 15 Aug 2023 13:16:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237412AbjHONQ2 (ORCPT ); Tue, 15 Aug 2023 09:16:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237413AbjHONQM (ORCPT ); Tue, 15 Aug 2023 09:16:12 -0400 Received: from relmlie5.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8EDAE1987; Tue, 15 Aug 2023 06:16:11 -0700 (PDT) X-IronPort-AV: E=Sophos;i="6.01,174,1684767600"; d="scan'208";a="173003484" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 15 Aug 2023 22:16:11 +0900 Received: from localhost.localdomain (unknown [10.226.92.136]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 845804002979; Tue, 15 Aug 2023 22:16:08 +0900 (JST) From: Biju Das To: Linus Walleij Cc: Biju Das , Geert Uytterhoeven , Lad Prabhakar , Fabrizio Castro , linux-renesas-soc@vger.kernel.org, linux-gpio@vger.kernel.org, stable@kernel.org Subject: [PATCH v3 2/3] pinctrl: renesas: rzv2m: Fix NULL pointer dereference in rzv2m_dt_subnode_to_map() Date: Tue, 15 Aug 2023 14:15:57 +0100 Message-Id: <20230815131558.33787-3-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230815131558.33787-1-biju.das.jz@bp.renesas.com> References: <20230815131558.33787-1-biju.das.jz@bp.renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Fix the below random NULL pointer crash during boot by serializing groups and functions creation in rzv2m_dt_subnode_to_map() with mutex lock. Crash logs: pc : __pi_strcmp+0x20/0x140 lr : pinmux_func_name_to_selector+0x68/0xa4 Call trace: __pi_strcmp+0x20/0x140 pinmux_generic_add_function+0x34/0xcc rzv2m_dt_subnode_to_map+0x2e4/0x418 rzv2m_dt_node_to_map+0x15c/0x18c pinctrl_dt_to_map+0x218/0x37c create_pinctrl+0x70/0x3d8 While at it, add comment for lock. Fixes: 92a9b8252576 ("pinctrl: renesas: Add RZ/V2M pin and gpio controller driver") Cc: stable@kernel.org Signed-off-by: Biju Das Reviewed-by: Geert Uytterhoeven --- v2->v3: * Added comment for lock. * Moved map allocation down to reduce lock section. * Added locks for maps and pinctrl group and function creation/remove calls * Added unlock_and_done label for lock error path. v1->v2: * Updated crash logs as per submitting patches doc. --- drivers/pinctrl/renesas/pinctrl-rzv2m.c | 56 ++++++++++++++----------- 1 file changed, 32 insertions(+), 24 deletions(-) diff --git a/drivers/pinctrl/renesas/pinctrl-rzv2m.c b/drivers/pinctrl/renesas/pinctrl-rzv2m.c index c73784b8b4ba..19586a0861a4 100644 --- a/drivers/pinctrl/renesas/pinctrl-rzv2m.c +++ b/drivers/pinctrl/renesas/pinctrl-rzv2m.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -123,7 +124,8 @@ struct rzv2m_pinctrl { struct gpio_chip gpio_chip; struct pinctrl_gpio_range gpio_range; - spinlock_t lock; + spinlock_t lock; /* lock read/write registers */ + struct mutex mutex; /* serialize adding groups and functions */ }; static const unsigned int drv_1_8V_group2_uA[] = { 1800, 3800, 7800, 11000 }; @@ -269,28 +271,6 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev, if (num_pins) nmaps += num_pins; - maps = krealloc_array(maps, nmaps, sizeof(*maps), GFP_KERNEL); - if (!maps) { - ret = -ENOMEM; - goto done; - } - - *map = maps; - *num_maps = nmaps; - if (num_pins) { - of_property_for_each_string(np, "pins", prop, pin) { - ret = rzv2m_map_add_config(&maps[idx], pin, - PIN_MAP_TYPE_CONFIGS_PIN, - configs, num_configs); - if (ret < 0) - goto done; - - idx++; - } - ret = 0; - goto done; - } - pins = devm_kcalloc(pctrl->dev, num_pinmux, sizeof(*pins), GFP_KERNEL); psel_val = devm_kcalloc(pctrl->dev, num_pinmux, sizeof(*psel_val), GFP_KERNEL); @@ -322,11 +302,34 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev, name = np->name; } + mutex_lock(&pctrl->mutex); + maps = krealloc_array(maps, nmaps, sizeof(*maps), GFP_KERNEL); + if (!maps) { + ret = -ENOMEM; + goto unlock_and_done; + } + + *map = maps; + *num_maps = nmaps; + if (num_pins) { + of_property_for_each_string(np, "pins", prop, pin) { + ret = rzv2m_map_add_config(&maps[idx], pin, + PIN_MAP_TYPE_CONFIGS_PIN, + configs, num_configs); + if (ret < 0) + goto unlock_and_done; + + idx++; + } + ret = 0; + goto unlock_and_done; + } + /* Register a single pin group listing all the pins we read from DT */ gsel = pinctrl_generic_add_group(pctldev, name, pins, num_pinmux, NULL); if (gsel < 0) { ret = gsel; - goto done; + goto unlock_and_done; } /* @@ -340,6 +343,8 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev, goto remove_group; } + mutex_unlock(&pctrl->mutex); + maps[idx].type = PIN_MAP_TYPE_MUX_GROUP; maps[idx].data.mux.group = name; maps[idx].data.mux.function = name; @@ -351,6 +356,8 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev, remove_group: pinctrl_generic_remove_group(pctldev, gsel); +unlock_and_done: + mutex_unlock(&pctrl->mutex); done: *index = idx; kfree(configs); @@ -1065,6 +1072,7 @@ static int rzv2m_pinctrl_probe(struct platform_device *pdev) "failed to enable GPIO clk\n"); spin_lock_init(&pctrl->lock); + mutex_init(&pctrl->mutex); platform_set_drvdata(pdev, pctrl);