Enable RW access to KPKEYS_PKEY_PGTABLES (used to map page table
pages) if switching to KPKEYS_CTX_PGTABLES, otherwise only grant RO
access.

Signed-off-by: Kevin Brodsky <[email protected]>
---
 arch/arm64/include/asm/kpkeys.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/kpkeys.h b/arch/arm64/include/asm/kpkeys.h
index ea915f78936b..0c155b970582 100644
--- a/arch/arm64/include/asm/kpkeys.h
+++ b/arch/arm64/include/asm/kpkeys.h
@@ -12,7 +12,8 @@
  * Equivalent to por_set_kpkeys_context(0, KPKEYS_CTX_DEFAULT), but can also be
  * used in assembly.
  */
-#define POR_EL1_INIT   POR_ELx_PERM_PREP(KPKEYS_PKEY_DEFAULT, POE_RWX)
+#define POR_EL1_INIT   (POR_ELx_PERM_PREP(KPKEYS_PKEY_DEFAULT, POE_RWX) | \
+                        POR_ELx_PERM_PREP(KPKEYS_PKEY_PGTABLES, POE_R))
 
 #ifndef __ASSEMBLY__
 
@@ -33,6 +34,8 @@ static inline bool arch_supports_kpkeys_early(void)
 static inline u64 por_set_kpkeys_context(u64 por, int ctx)
 {
        por = por_elx_set_pkey_perms(por, KPKEYS_PKEY_DEFAULT, POE_RWX);
+       por = por_elx_set_pkey_perms(por, KPKEYS_PKEY_PGTABLES,
+                                    ctx == KPKEYS_CTX_PGTABLES ? POE_RW : 
POE_R);
 
        return por;
 }

-- 
2.51.2


Reply via email to