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| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2019-03-11 09:30:34 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-04-21 15:11:46 +0200 |
| commit | 2679f9bd0abafb3044bcbaac0600b32159ac8bf2 (patch) | |
| tree | 77543dc9837adb96bd9bd4ee3465015a47c08029 /arch/powerpc/platforms | |
| parent | powerpc/8xx: Add Kernel Userspace Execution Prevention (diff) | |
| download | linux-2679f9bd0abafb3044bcbaac0600b32159ac8bf2.tar.xz linux-2679f9bd0abafb3044bcbaac0600b32159ac8bf2.zip | |
powerpc/8xx: Add Kernel Userspace Access Protection
This patch adds Kernel Userspace Access Protection on the 8xx.
When a page is RO or RW, it is set RO or RW for Key 0 and NA
for Key 1.
Up to now, the User group is defined with Key 0 for both User and
Supervisor.
By changing the group to Key 0 for User and Key 1 for Supervisor,
this patch prevents the Kernel from being able to access user data.
At exception entry, the kernel saves SPRN_MD_AP in the regs struct,
and reapply the protection. At exception exit it restores SPRN_MD_AP
with the value saved on exception entry.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Drop allow_read/write_to/from_user() as they're now in kup.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/Kconfig.cputype | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 00fa0d110dcb..ab586963893a 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -35,6 +35,7 @@ config PPC_8xx select FSL_SOC select SYS_SUPPORTS_HUGETLBFS select PPC_HAVE_KUEP + select PPC_HAVE_KUAP config 40x bool "AMCC 40x" |