[PATCH RFC v9 17/25] arm64: kpkeys: Support KPKEYS_CTX_PGTABLES
Kevin Brodsky <[email protected]>
| Newsgroups | org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-hardening,org.kvack.linux-mm |
|---|---|
| Message-ID | <[email protected]> |
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 284039e9a244..00e7e5956794 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(0, POE_RWX) +#define POR_EL1_INIT (POR_ELx_PERM_PREP(0, 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, enum kpkeys_ctx ctx) { por = por_elx_set_pkey_perms(por, 0, 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