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/resctrl/Kconfig | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 drivers/resctrl/Kconfig (limited to 'drivers/resctrl/Kconfig') diff --git a/drivers/resctrl/Kconfig b/drivers/resctrl/Kconfig new file mode 100644 index 000000000..672abea3b --- /dev/null +++ b/drivers/resctrl/Kconfig @@ -0,0 +1,31 @@ +menuconfig ARM64_MPAM_DRIVER + bool "MPAM driver" + depends on ARM64 && ARM64_MPAM + select ACPI_MPAM if ACPI + help + Memory System Resource Partitioning and Monitoring (MPAM) driver for + System IP, e.g. caches and memory controllers. + +if ARM64_MPAM_DRIVER + +config ARM64_MPAM_DRIVER_DEBUG + bool "Enable debug messages from the MPAM driver" + help + Say yes here to enable debug messages from the MPAM driver. + +config MPAM_KUNIT_TEST + bool "KUnit tests for MPAM driver " if !KUNIT_ALL_TESTS + depends on KUNIT=y + default KUNIT_ALL_TESTS + help + Enable this option to run tests in the MPAM driver. + + If unsure, say N. + +endif + +config ARM64_MPAM_RESCTRL_FS + bool + default y if ARM64_MPAM_DRIVER && RESCTRL_FS + select RESCTRL_RMID_DEPENDS_ON_CLOSID + select RESCTRL_ASSIGN_FIXED -- cgit v1.3.1