#include <asm/book3s/64/hash-pkey.h>
+extern u64 __ro_after_init default_uamor;
+
static inline u64 vmflag_to_pte_pkey_bits(u64 vm_flags)
{
if (!mmu_has_feature(MMU_FTR_PKEY))
#ifdef CONFIG_PPC_MEM_KEYS
unsigned long amr;
unsigned long iamr;
- unsigned long uamor;
#endif
#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
void* kvm_shadow_vcpu; /* KVM internal data */
static int pkey_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
{
+ int ret;
+
BUILD_BUG_ON(TSO(amr) + sizeof(unsigned long) != TSO(iamr));
- BUILD_BUG_ON(TSO(iamr) + sizeof(unsigned long) != TSO(uamor));
if (!arch_pkeys_enabled())
return -ENODEV;
- return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr,
- 0, ELF_NPKEY * sizeof(unsigned long));
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr,
+ 0, 2 * sizeof(unsigned long));
+ if (ret)
+ return ret;
+
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &default_uamor,
+ 2 * sizeof(unsigned long), 3 * sizeof(unsigned long));
+ return ret;
}
static int pkey_set(struct task_struct *target, const struct user_regset *regset,
if (ret)
return ret;
- /* UAMOR determines which bits of the AMR can be set from userspace. */
- target->thread.amr = (new_amr & target->thread.uamor) |
- (target->thread.amr & ~target->thread.uamor);
+ /*
+ * UAMOR determines which bits of the AMR can be set from userspace.
+ * UAMOR value 0b11 indicates that the AMR value can be modified
+ * from userspace. If the kernel is using a specific key, we avoid
+ * userspace modifying the AMR value for that key by masking them
+ * via UAMOR 0b00.
+ *
+ * Pick the AMR values for the keys that kernel is using. This
+ * will be indicated by the ~default_uamor bits.
+ */
+ target->thread.amr = (new_amr & default_uamor) | (target->thread.amr & ~default_uamor);
return 0;
}
#include <asm/asm-prototypes.h>
#include <asm/cpu_has_feature.h>
#include <asm/ftrace.h>
+#include <asm/kup.h>
#ifdef DEBUG
#include <asm/udbg.h>
if (cpu_has_feature(CPU_FTR_ARCH_206)
&& cpu_has_feature(CPU_FTR_HVMODE))
tlbiel_all();
+
+#ifdef CONFIG_PPC_MEM_KEYS
+ mtspr(SPRN_UAMOR, default_uamor);
+#endif
}
#endif /* CONFIG_SMP */
*/
static u64 default_amr = ~0x0UL;
static u64 default_iamr = 0x5555555555555555UL;
-
-/* Allow all keys to be modified by default */
-static u64 default_uamor = ~0x0UL;
+u64 default_uamor __ro_after_init;
/*
* Key used to implement PROT_EXEC mmap. Denies READ/WRITE
* We pick key 2 because 0 is special key and 1 is reserved as per ISA.
/* scan the device tree for pkey feature */
pkeys_total = scan_pkey_feature();
- if (!pkeys_total) {
- /* No support for pkey. Mark it disabled */
- return;
- }
+ if (!pkeys_total)
+ goto out;
+
+ /* Allow all keys to be modified by default */
+ default_uamor = ~0x0UL;
cur_cpu_spec->mmu_features |= MMU_FTR_PKEY;
initial_allocation_mask |= reserved_allocation_mask;
pr_info("Enabling pkeys with max key count %d\n", num_pkey);
+out:
+ /*
+ * Setup uamor on boot cpu
+ */
+ mtspr(SPRN_UAMOR, default_uamor);
+
return;
}
return mfspr(SPRN_UAMOR);
}
-static inline void write_uamor(u64 value)
-{
- mtspr(SPRN_UAMOR, value);
-}
-
static bool is_pkey_enabled(int pkey)
{
u64 uamor = read_uamor();
*/
thread->amr = read_amr();
thread->iamr = read_iamr();
- thread->uamor = read_uamor();
}
void thread_pkey_regs_restore(struct thread_struct *new_thread,
write_amr(new_thread->amr);
if (old_thread->iamr != new_thread->iamr)
write_iamr(new_thread->iamr);
- if (old_thread->uamor != new_thread->uamor)
- write_uamor(new_thread->uamor);
}
void thread_pkey_regs_init(struct thread_struct *thread)
thread->amr = default_amr;
thread->iamr = default_iamr;
- thread->uamor = default_uamor;
write_amr(default_amr);
write_iamr(default_iamr);
- write_uamor(default_uamor);
}
int execute_only_pkey(struct mm_struct *mm)
/* Make sure userspace can't change the AMR */
mtspr(SPRN_UAMOR, 0);
+
+ /*
+ * Set the default kernel AMR values on all cpus.
+ */
mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
isync();
}