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/gpu/host1x/Kconfig | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 drivers/gpu/host1x/Kconfig (limited to 'drivers/gpu/host1x/Kconfig') diff --git a/drivers/gpu/host1x/Kconfig b/drivers/gpu/host1x/Kconfig new file mode 100644 index 000000000..e6c78ae20 --- /dev/null +++ b/drivers/gpu/host1x/Kconfig @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: GPL-2.0-only + +config TEGRA_HOST1X_CONTEXT_BUS + bool + +config TEGRA_HOST1X + tristate "NVIDIA Tegra host1x driver" + depends on ARCH_TEGRA || COMPILE_TEST + select DMA_SHARED_BUFFER + select TEGRA_HOST1X_CONTEXT_BUS + select IOMMU_IOVA + help + Driver for the NVIDIA Tegra host1x hardware. + + The Tegra host1x module is the DMA engine for register access to + Tegra's graphics- and multimedia-related modules. The modules served + by host1x are referred to as clients. host1x includes some other + functionality, such as synchronization. + +if TEGRA_HOST1X + +config TEGRA_HOST1X_FIREWALL + bool "Enable HOST1X security firewall" + default y + help + Say yes if kernel should protect command streams from tampering. + + If unsure, choose Y. + +endif -- cgit v1.3.1