From patchwork Tue Aug 15 13:15:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 714190 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 03926C07E8A for ; Tue, 15 Aug 2023 13:16:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237418AbjHONQ1 (ORCPT ); Tue, 15 Aug 2023 09:16:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59330 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237412AbjHONQJ (ORCPT ); Tue, 15 Aug 2023 09:16:09 -0400 Received: from relmlie5.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 796001987; Tue, 15 Aug 2023 06:16:08 -0700 (PDT) X-IronPort-AV: E=Sophos;i="6.01,174,1684767600"; d="scan'208";a="173003478" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 15 Aug 2023 22:16:07 +0900 Received: from localhost.localdomain (unknown [10.226.92.136]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 2BAD740029AC; Tue, 15 Aug 2023 22:16:04 +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, Chris Paterson Subject: [PATCH v3 1/3] pinctrl: renesas: rzg2l: Fix NULL pointer dereference in rzg2l_dt_subnode_to_map() Date: Tue, 15 Aug 2023 14:15:56 +0100 Message-Id: <20230815131558.33787-2-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 pinctrl group and function creation/remove calls in rzg2l_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 rzg2l_dt_subnode_to_map+0x314/0x44c rzg2l_dt_node_to_map+0x164/0x194 pinctrl_dt_to_map+0x218/0x37c create_pinctrl+0x70/0x3d8 While at it, add comments for bitmap_lock and lock. Fixes: c4c4637eb57f ("pinctrl: renesas: Add RZ/G2L pin and gpio controller driver") Cc: stable@kernel.org Tested-by: Chris Paterson Signed-off-by: Biju Das Reviewed-by: Geert Uytterhoeven --- v2->v3: * Added comment for bitmap_lock and 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-rzg2l.c | 58 ++++++++++++++----------- 1 file changed, 33 insertions(+), 25 deletions(-) diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c index 4f34f8f24bde..571a32d2f697 100644 --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -149,10 +150,11 @@ struct rzg2l_pinctrl { struct gpio_chip gpio_chip; struct pinctrl_gpio_range gpio_range; DECLARE_BITMAP(tint_slot, RZG2L_TINT_MAX_INTERRUPT); - spinlock_t bitmap_lock; + spinlock_t bitmap_lock; /* protect tint_slot bitmap */ unsigned int hwirq[RZG2L_TINT_MAX_INTERRUPT]; - spinlock_t lock; + spinlock_t lock; /* lock read/write registers */ + struct mutex mutex; /* serialize adding groups and functions */ }; static const unsigned int iolh_groupa_mA[] = { 2, 4, 8, 12 }; @@ -309,28 +311,6 @@ static int rzg2l_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 = rzg2l_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); @@ -362,11 +342,34 @@ static int rzg2l_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 = rzg2l_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; } /* @@ -380,6 +383,8 @@ static int rzg2l_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; @@ -391,6 +396,8 @@ static int rzg2l_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); @@ -1503,6 +1510,7 @@ static int rzg2l_pinctrl_probe(struct platform_device *pdev) spin_lock_init(&pctrl->lock); spin_lock_init(&pctrl->bitmap_lock); + mutex_init(&pctrl->mutex); platform_set_drvdata(pdev, pctrl);