dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted

When dma_device_put() drops the last reference on chan->device->ref,
dma_device_release() runs and may free the dma_device along with its
channels.

dma_chan_put() then still reads chan->device->owner via
dma_chan_to_owner() for the trailing module_put(). KASAN catches it:

	slab-use-after-free in dma_chan_put+0x3e6/0x4c0
	Read of size 8 by task insmod/6319
	Freed by task 6319:
	  kfree+0x225/0x470
	  dma_chan_put+0x395/0x4c0
	  dmaengine_put+0xf8/0x160

Cache the module owner in dma_chan_put() before the put so the trailing
module_put() does not need chan->device.

Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct")
Suggested-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
new file mode 100644
index 000000000..34469711c
--- /dev/null
+++ b/drivers/video/backlight/Makefile
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: GPL-2.0
+# Backlight & LCD drivers
+
+obj-$(CONFIG_LCD_AMS369FG06)		+= ams369fg06.o
+obj-$(CONFIG_LCD_CLASS_DEVICE)		+= lcd.o
+obj-$(CONFIG_LCD_CORGI)			+= corgi_lcd.o
+obj-$(CONFIG_LCD_HP700)			+= jornada720_lcd.o
+obj-$(CONFIG_LCD_HX8357)		+= hx8357.o
+obj-$(CONFIG_LCD_ILI922X)		+= ili922x.o
+obj-$(CONFIG_LCD_ILI9320)		+= ili9320.o
+obj-$(CONFIG_LCD_L4F00242T03)		+= l4f00242t03.o
+obj-$(CONFIG_LCD_LMS283GF05)		+= lms283gf05.o
+obj-$(CONFIG_LCD_LMS501KF03)		+= lms501kf03.o
+obj-$(CONFIG_LCD_LTV350QV)		+= ltv350qv.o
+obj-$(CONFIG_LCD_OTM3225A)		+= otm3225a.o
+obj-$(CONFIG_LCD_PLATFORM)		+= platform_lcd.o
+obj-$(CONFIG_LCD_TDO24M)		+= tdo24m.o
+obj-$(CONFIG_LCD_VGG2432A4)		+= vgg2432a4.o
+
+obj-$(CONFIG_BACKLIGHT_88PM860X)	+= 88pm860x_bl.o
+obj-$(CONFIG_BACKLIGHT_AAT2870)		+= aat2870_bl.o
+obj-$(CONFIG_BACKLIGHT_ADP5520)		+= adp5520_bl.o
+obj-$(CONFIG_BACKLIGHT_ADP8860)		+= adp8860_bl.o
+obj-$(CONFIG_BACKLIGHT_ADP8870)		+= adp8870_bl.o
+obj-$(CONFIG_BACKLIGHT_APPLE)		+= apple_bl.o
+obj-$(CONFIG_BACKLIGHT_APPLE_DWI)	+= apple_dwi_bl.o
+obj-$(CONFIG_BACKLIGHT_AS3711)		+= as3711_bl.o
+obj-$(CONFIG_BACKLIGHT_AW99706)		+= aw99706.o
+obj-$(CONFIG_BACKLIGHT_BD6107)		+= bd6107.o
+obj-$(CONFIG_BACKLIGHT_CGBC)		+= cgbc_bl.o
+obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE)	+= backlight.o
+obj-$(CONFIG_BACKLIGHT_DA903X)		+= da903x_bl.o
+obj-$(CONFIG_BACKLIGHT_DA9052)		+= da9052_bl.o
+obj-$(CONFIG_BACKLIGHT_EP93XX)		+= ep93xx_bl.o
+obj-$(CONFIG_BACKLIGHT_GPIO)		+= gpio_backlight.o
+obj-$(CONFIG_BACKLIGHT_HP680)		+= hp680_bl.o
+obj-$(CONFIG_BACKLIGHT_HP700)		+= jornada720_bl.o
+obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO)	+= ipaq_micro_bl.o
+obj-$(CONFIG_BACKLIGHT_KTD253)		+= ktd253-backlight.o
+obj-$(CONFIG_BACKLIGHT_KTD2801)		+= ktd2801-backlight.o
+obj-$(CONFIG_BACKLIGHT_KTZ8866)		+= ktz8866.o
+obj-$(CONFIG_BACKLIGHT_LM3509)		+= lm3509_bl.o
+obj-$(CONFIG_BACKLIGHT_LM3533)		+= lm3533_bl.o
+obj-$(CONFIG_BACKLIGHT_LM3630A)		+= lm3630a_bl.o
+obj-$(CONFIG_BACKLIGHT_LM3639)		+= lm3639_bl.o
+obj-$(CONFIG_BACKLIGHT_LOCOMO)		+= locomolcd.o
+obj-$(CONFIG_BACKLIGHT_LP855X)		+= lp855x_bl.o
+obj-$(CONFIG_BACKLIGHT_LP8788)		+= lp8788_bl.o
+obj-$(CONFIG_BACKLIGHT_LV5207LP)	+= lv5207lp.o
+obj-$(CONFIG_BACKLIGHT_MAX25014)	+= max25014.o
+obj-$(CONFIG_BACKLIGHT_MAX8925)		+= max8925_bl.o
+obj-$(CONFIG_BACKLIGHT_MP3309C)		+= mp3309c.o
+obj-$(CONFIG_BACKLIGHT_MT6370)		+= mt6370-backlight.o
+obj-$(CONFIG_BACKLIGHT_OMAP1)		+= omap1_bl.o
+obj-$(CONFIG_BACKLIGHT_PANDORA)		+= pandora_bl.o
+obj-$(CONFIG_BACKLIGHT_PWM)		+= pwm_bl.o
+obj-$(CONFIG_BACKLIGHT_QCOM_WLED)	+= qcom-wled.o
+obj-$(CONFIG_BACKLIGHT_RT4831)		+= rt4831-backlight.o
+obj-$(CONFIG_BACKLIGHT_SAHARA)		+= kb3886_bl.o
+obj-$(CONFIG_BACKLIGHT_SY7758)		+= sy7758.o
+obj-$(CONFIG_BACKLIGHT_SKY81452)	+= sky81452-backlight.o
+obj-$(CONFIG_BACKLIGHT_TPS65217)	+= tps65217_bl.o
+obj-$(CONFIG_BACKLIGHT_WM831X)		+= wm831x_bl.o
+obj-$(CONFIG_BACKLIGHT_ARCXCNN) 	+= arcxcnn_bl.o
+obj-$(CONFIG_BACKLIGHT_RAVE_SP)		+= rave-sp-backlight.o
+obj-$(CONFIG_BACKLIGHT_LED)		+= led_bl.o