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 --- security/integrity/Makefile | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 security/integrity/Makefile (limited to 'security/integrity/Makefile') diff --git a/security/integrity/Makefile b/security/integrity/Makefile new file mode 100644 index 000000000..45dfdedbd --- /dev/null +++ b/security/integrity/Makefile @@ -0,0 +1,24 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for caching inode integrity data (iint) +# + +obj-$(CONFIG_INTEGRITY) += integrity.o + +integrity-y := iint.o +integrity-$(CONFIG_INTEGRITY_AUDIT) += integrity_audit.o +integrity-$(CONFIG_INTEGRITY_SIGNATURE) += digsig.o +integrity-$(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) += digsig_asymmetric.o +integrity-$(CONFIG_INTEGRITY_PLATFORM_KEYRING) += platform_certs/platform_keyring.o +integrity-$(CONFIG_INTEGRITY_MACHINE_KEYRING) += platform_certs/machine_keyring.o +integrity-$(CONFIG_LOAD_UEFI_KEYS) += platform_certs/efi_parser.o \ + platform_certs/load_uefi.o \ + platform_certs/keyring_handler.o +integrity-$(CONFIG_LOAD_IPL_KEYS) += platform_certs/load_ipl_s390.o +integrity-$(CONFIG_LOAD_PPC_KEYS) += platform_certs/efi_parser.o \ + platform_certs/load_powerpc.o \ + platform_certs/keyring_handler.o +integrity-$(CONFIG_EFI) += efi_secureboot.o +# The relative order of the 'ima' and 'evm' LSMs depends on the order below. +obj-$(CONFIG_IMA) += ima/ +obj-$(CONFIG_EVM) += evm/ -- cgit v1.3.1