Merge tag 'vfio-v4.21-rc1' of git://github.com/awilliam/linux-vfio

[sfrench/cifs-2.6.git] / arch / arm64 / kernel / ptrace.c

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 1710a2d0166942ae6b1aca9db8ee6dca6d976676..9dce33b0e26042b4d70e8a1ae35c0b1f39195e05 100644 (file)
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -46,6 +46,7 @@
 #include <asm/debug-monitors.h>
 #include <asm/fpsimd.h>
 #include <asm/pgtable.h>
+#include <asm/pointer_auth.h>
 #include <asm/stacktrace.h>
 #include <asm/syscall.h>
 #include <asm/traps.h>
@@ -956,6 +957,30 @@ out:
 
 #endif /* CONFIG_ARM64_SVE */
 
+#ifdef CONFIG_ARM64_PTR_AUTH
+static int pac_mask_get(struct task_struct *target,
+                       const struct user_regset *regset,
+                       unsigned int pos, unsigned int count,
+                       void *kbuf, void __user *ubuf)
+{
+       /*
+        * The PAC bits can differ across data and instruction pointers
+        * depending on TCR_EL1.TBID*, which we may make use of in future, so
+        * we expose separate masks.
+        */
+       unsigned long mask = ptrauth_user_pac_mask();
+       struct user_pac_mask uregs = {
+               .data_mask = mask,
+               .insn_mask = mask,
+       };
+
+       if (!system_supports_address_auth())
+               return -EINVAL;
+
+       return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &uregs, 0, -1);
+}
+#endif /* CONFIG_ARM64_PTR_AUTH */
+
 enum aarch64_regset {
        REGSET_GPR,
        REGSET_FPR,
@@ -968,6 +993,9 @@ enum aarch64_regset {
 #ifdef CONFIG_ARM64_SVE
        REGSET_SVE,
 #endif
+#ifdef CONFIG_ARM64_PTR_AUTH
+       REGSET_PAC_MASK,
+#endif
 };
 
 static const struct user_regset aarch64_regsets[] = {
@@ -1037,6 +1065,16 @@ static const struct user_regset aarch64_regsets[] = {
                .get_size = sve_get_size,
        },
 #endif
+#ifdef CONFIG_ARM64_PTR_AUTH
+       [REGSET_PAC_MASK] = {
+               .core_note_type = NT_ARM_PAC_MASK,
+               .n = sizeof(struct user_pac_mask) / sizeof(u64),
+               .size = sizeof(u64),
+               .align = sizeof(u64),
+               .get = pac_mask_get,
+               /* this cannot be set dynamically */
+       },
+#endif
 };
 
 static const struct user_regset_view user_aarch64_view = {