From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Kozlowski Subject: [RFC 3/4] clk: samsung: exynos5: Fix kfree() of const memory on setting driver_override Date: Mon, 18 Feb 2019 11:15:59 +0100 Message-ID: <1550484960-2392-4-git-send-email-krzk@kernel.org> References: <1550484960-2392-1-git-send-email-krzk@kernel.org> Return-path: In-Reply-To: <1550484960-2392-1-git-send-email-krzk@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Russell King , Mark Brown , linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, Greg Kroah-Hartman , "Rafael J. Wysocki" , Sylwester Nawrocki , Tomasz Figa , Chanwoo Choi , Michael Turquette , Stephen Boyd , Kukjin Kim , Krzysztof Kozlowski , Andy Gross , David Brown , Srinivas Kandagatla , linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, alsa-devel@alsa-project List-Id: alsa-devel@alsa-project.org Platform driver driver_override field should not be initialized from const memory because the core later kfree() it. If driver_override is manually set later through sysfs, kfree() of old value leads to: $ echo "new_value" > /sys/bus/platform/drivers/.../driver_override kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [] (platform_set_driver_override+0x84/0xac) (platform_set_driver_override) from [] (driver_override_store+0x20/0x34) (driver_override_store) from [] (kernfs_fop_write+0x100/0x1dc) (kernfs_fop_write) from [] (__vfs_write+0x2c/0x17c) (__vfs_write) from [] (vfs_write+0xa4/0x188) (vfs_write) from [] (ksys_write+0x4c/0xac) (ksys_write) from [] (ret_fast_syscall+0x0/0x28) Signed-off-by: Krzysztof Kozlowski --- drivers/clk/samsung/clk-exynos5-subcmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/clk/samsung/clk-exynos5-subcmu.c b/drivers/clk/samsung/clk-exynos5-subcmu.c index d07ef26bd052..880d92ad20e8 100644 --- a/drivers/clk/samsung/clk-exynos5-subcmu.c +++ b/drivers/clk/samsung/clk-exynos5-subcmu.c @@ -143,7 +143,7 @@ static int __init exynos5_clk_register_subcmu(struct device *parent, return -ENOMEM; pdev->dev.parent = parent; - pdev->driver_override = "exynos5-subcmu"; + platform_set_driver_override(pdev, "exynos5-subcmu"); platform_set_drvdata(pdev, (void *)info); of_genpd_add_device(&genpdspec, &pdev->dev); ret = platform_device_add(pdev); -- 2.7.4