From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() 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 Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- drivers/video/fbdev/stifb.c | 1531 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1531 insertions(+) create mode 100644 drivers/video/fbdev/stifb.c (limited to 'drivers/video/fbdev/stifb.c') diff --git a/drivers/video/fbdev/stifb.c b/drivers/video/fbdev/stifb.c new file mode 100644 index 000000000..8e5bac275 --- /dev/null +++ b/drivers/video/fbdev/stifb.c @@ -0,0 +1,1531 @@ +/* + * linux/drivers/video/stifb.c - + * Low level Frame buffer driver for HP workstations with + * STI (standard text interface) video firmware. + * + * Copyright (C) 2001-2006 Helge Deller + * Portions Copyright (C) 2001 Thomas Bogendoerfer + * + * Based on: + * - linux/drivers/video/artistfb.c -- Artist frame buffer driver + * Copyright (C) 2000 Philipp Rumpf + * - based on skeletonfb, which was + * Created 28 Dec 1997 by Geert Uytterhoeven + * - HP Xhp cfb-based X11 window driver for XFree86 + * (c)Copyright 1992 Hewlett-Packard Co. + * + * + * The following graphics display devices (NGLE family) are supported by this driver: + * + * HPA4070A known as "HCRX", a 1280x1024 color device with 8 planes + * HPA4071A known as "HCRX24", a 1280x1024 color device with 24 planes, + * optionally available with a hardware accelerator as HPA4071A_Z + * HPA1659A known as "CRX", a 1280x1024 color device with 8 planes + * HPA1439A known as "CRX24", a 1280x1024 color device with 24 planes, + * optionally available with a hardware accelerator. + * HPA1924A known as "GRX", a 1280x1024 grayscale device with 8 planes + * HPA2269A known as "Dual CRX", a 1280x1024 color device with 8 planes, + * implements support for two displays on a single graphics card. + * HP710C internal graphics support optionally available on the HP9000s710 SPU, + * supports 1280x1024 color displays with 8 planes. + * HP710G same as HP710C, 1280x1024 grayscale only + * HP710L same as HP710C, 1024x768 color only + * HP712 internal graphics support on HP9000s712 SPU, supports 640x480, + * 1024x768 or 1280x1024 color displays on 8 planes (Artist) + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +/* TODO: + * - 1bpp mode is completely untested + * - add support for h/w acceleration + * - add hardware cursor + * - automatically disable double buffering (e.g. on RDI precisionbook laptop) + */ + + +/* on supported graphic devices you may: + * #define FALLBACK_TO_1BPP to fall back to 1 bpp, or + * #undef FALLBACK_TO_1BPP to reject support for unsupported cards */ +#undef FALLBACK_TO_1BPP + +#undef DEBUG_STIFB_REGS /* debug sti register accesses */ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include /* for HP-UX compatibility */ +#include + +#include