linux/arch
Benjamin Gray bbd99922d0 powerpc/dexcr: Reset DEXCR value across exec
Inheriting the DEXCR across exec can have security and usability
concerns. If a program is compiled with hash instructions it generally
expects to run with NPHIE enabled. But if the parent process disables
NPHIE then if it's not careful it will be disabled for any children too
and the protection offered by hash checks is basically worthless.

This patch introduces a per-process reset value that new execs in a
particular process tree are initialized with. This enables fine grained
control over what DEXCR value child processes run with by default.
For example, containers running legacy binaries that expect hash
instructions to act as NOPs could configure the reset value of the
container root to control the default reset value for all members of
the container.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
[mpe: Add missing SPDX tag on dexcr.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240417112325.728010-4-bgray@linux.ibm.com
2024-05-03 20:46:51 +10:00
..
alpha Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
arc - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
arm ARM: prctl: reject PR_SET_MDWE on pre-ARMv6 2024-03-26 11:07:22 -07:00
arm64 Including fixes from bpf, WiFi and netfilter. 2024-03-28 13:09:37 -07:00
csky - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
hexagon hexagon: vmlinux.lds.S: handle attributes section 2024-03-26 11:07:23 -07:00
loongarch LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
m68k TTY/Serial driver update for 6.9-rc1 2024-03-21 12:44:10 -07:00
microblaze arch: define CONFIG_PAGE_SIZE_*KB on all architectures 2024-03-06 19:29:09 +01:00
mips MIPS: move unselectable FIT_IMAGE_FDT_EPM5 out of the "System type" choice 2024-03-27 01:58:34 +09:00
nios2 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
openrisc OpenRISC updates for 6.9 2024-03-14 15:53:10 -07:00
parisc prctl: generalize PR_SET_MDWE support check to be per-arch 2024-03-26 11:07:22 -07:00
powerpc powerpc/dexcr: Reset DEXCR value across exec 2024-05-03 20:46:51 +10:00
riscv Including fixes from bpf, WiFi and netfilter. 2024-03-28 13:09:37 -07:00
s390 bpf-for-netdev 2024-03-26 12:55:18 +01:00
sh sh updates for v6.9 2024-03-21 10:13:47 -07:00
sparc This includes the following changes related to sparc for v6.9: 2024-03-15 12:47:21 -07:00
um Devicetree updates for v6.9: 2024-03-15 12:37:59 -07:00
x86 - Define the correct set of default hw events on AMD Zen4 2024-03-31 10:43:11 -07:00
xtensa - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
.gitignore
Kconfig hardening fixes for v6.9-rc1 2024-03-23 08:43:21 -07:00