From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- drivers/video/Kconfig | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 drivers/video/Kconfig (limited to 'drivers/video/Kconfig') diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig new file mode 100644 index 000000000..a7144d275 --- /dev/null +++ b/drivers/video/Kconfig @@ -0,0 +1,95 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Video configuration +# + +menu "Graphics support" + +config APERTURE_HELPERS + bool + help + Support tracking and hand-over of aperture ownership. Required + by graphics drivers for firmware-provided framebuffers. + +config SCREEN_INFO + bool + default n + +config STI_CORE + bool + depends on PARISC + help + STI refers to the HP "Standard Text Interface" which is a set of + BIOS routines contained in a ROM chip in HP PA-RISC based machines. + +config VIDEO + bool + default n + +source "drivers/auxdisplay/Kconfig" + +if HAS_IOMEM + +config HAVE_FB_ATMEL + bool + +source "drivers/char/agp/Kconfig" + +source "drivers/gpu/vga/Kconfig" + +source "drivers/gpu/Kconfig" +source "drivers/gpu/host1x/Kconfig" +source "drivers/gpu/ipu-v3/Kconfig" +source "drivers/gpu/nova-core/Kconfig" + +source "drivers/gpu/drm/Kconfig" + +menu "Frame buffer Devices" +source "drivers/video/fbdev/Kconfig" +endmenu + +source "drivers/video/backlight/Kconfig" + +config VGASTATE + tristate + default n + +config VIDEOMODE_HELPERS + bool + +config HDMI + bool + +endif # HAS_IOMEM + +config FIRMWARE_EDID + bool "Enable firmware EDID" + depends on EFI_GENERIC_STUB || X86 + help + This enables access to the EDID transferred from the firmware. + On EFI systems, the EDID comes from the same device as the + primary GOP. On x86 with BIOS, it comes from the VESA BIOS. + DRM display drivers will be able to export the information + to userspace. + + Also enable this if DDC/I2C transfers do not work for your driver + and if you are using nvidiafb, i810fb or savagefb. + + In general, choosing Y for this option is safe. If you + experience extremely long delays while booting before you get + something on your display, try setting this to N. Matrox cards in + combination with certain motherboards and monitors are known to + suffer from this problem. + +if VT + source "drivers/video/console/Kconfig" +endif + +if FB_CORE || SGI_NEWPORT_CONSOLE + source "drivers/video/logo/Kconfig" + +endif + +source "drivers/gpu/trace/Kconfig" + +endmenu -- cgit v1.3.1