diff options
| -rw-r--r-- | Documentation/arm64/pointer-authentication.txt | 5 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/ptrace.h | 13 | ||||
| -rw-r--r-- | arch/arm64/kernel/ptrace.c | 147 | ||||
| -rw-r--r-- | include/uapi/linux/elf.h | 2 |
4 files changed, 167 insertions, 0 deletions
diff --git a/Documentation/arm64/pointer-authentication.txt b/Documentation/arm64/pointer-authentication.txt index a25cd21290e9..5baca42ba146 100644 --- a/Documentation/arm64/pointer-authentication.txt +++ b/Documentation/arm64/pointer-authentication.txt @@ -78,6 +78,11 @@ bits can vary between the two. Note that the masks apply to TTBR0 addresses, and are not valid to apply to TTBR1 addresses (e.g. kernel pointers). +Additionally, when CONFIG_CHECKPOINT_RESTORE is also set, the kernel +will expose the NT_ARM_PACA_KEYS and NT_ARM_PACG_KEYS regsets (struct +user_pac_address_keys and struct user_pac_generic_keys). These can be +used to get and set the keys for a thread. + Virtualization -------------- diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h index 28d77c9ed531..d78623acb649 100644 --- a/arch/arm64/include/uapi/asm/ptrace.h +++ b/arch/arm64/include/uapi/asm/ptrace.h @@ -233,6 +233,19 @@ struct user_pac_mask { __u64 insn_mask; }; +/* pointer authentication keys (NT_ARM_PACA_KEYS, NT_ARM_PACG_KEYS) */ + +struct user_pac_address_keys { + __uint128_t apiakey; + __uint128_t apibkey; + __uint128_t apdakey; + __uint128_t apdbkey; +}; + +struct user_pac_generic_keys { + __uint128_t apgakey; +}; + #endif /* __ASSEMBLY__ */ #endif /* _UAPI__ASM_PTRACE_H */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 9dce33b0e260..a86413be5a2d 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -979,6 +979,131 @@ static int pac_mask_get(struct task_struct *target, return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &uregs, 0, -1); } + +#ifdef CONFIG_CHECKPOINT_RESTORE +static __uint128_t pac_key_to_user(const struct ptrauth_key *key) +{ + return (__uint128_t)key->hi << 64 | key->lo; +} + +static struct ptrauth_key pac_key_from_user(__uint128_t ukey) +{ + struct ptrauth_key key = { + .lo = (unsigned long)ukey, + .hi = (unsigned long)(ukey >> 64), + }; + + return key; +} + +static void pac_address_keys_to_user(struct user_pac_address_keys *ukeys, + const struct ptrauth_keys *keys) +{ + ukeys->apiakey = pac_key_to_user(&keys->apia); + ukeys->apibkey = pac_key_to_user(&keys->apib); + ukeys->apdakey = pac_key_to_user(&keys->apda); + ukeys->apdbkey = pac_key_to_user(&keys->apdb); +} + +static void pac_address_keys_from_user(struct ptrauth_keys *keys, + const struct user_pac_address_keys *ukeys) +{ + keys->apia = pac_key_from_user(ukeys->apiakey); + keys->apib = pac_key_from_user(ukeys->apibkey); + keys->apda = pac_key_from_user(ukeys->apdakey); + keys->apdb = pac_key_from_user(ukeys->apdbkey); +} + +static int pac_address_keys_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + struct ptrauth_keys *keys = &target->thread.keys_user; + struct user_pac_address_keys user_keys; + + if (!system_supports_address_auth()) + return -EINVAL; + + pac_address_keys_to_user(&user_keys, keys); + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &user_keys, 0, -1); +} + +static int pac_address_keys_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + struct ptrauth_keys *keys = &target->thread.keys_user; + struct user_pac_address_keys user_keys; + int ret; + + if (!system_supports_address_auth()) + return -EINVAL; + + pac_address_keys_to_user(&user_keys, keys); + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &user_keys, 0, -1); + if (ret) + return ret; + pac_address_keys_from_user(keys, &user_keys); + + return 0; +} + +static void pac_generic_keys_to_user(struct user_pac_generic_keys *ukeys, + const struct ptrauth_keys *keys) +{ + ukeys->apgakey = pac_key_to_user(&keys->apga); +} + +static void pac_generic_keys_from_user(struct ptrauth_keys *keys, + const struct user_pac_generic_keys *ukeys) +{ + keys->apga = pac_key_from_user(ukeys->apgakey); +} + +static int pac_generic_keys_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + struct ptrauth_keys *keys = &target->thread.keys_user; + struct user_pac_generic_keys user_keys; + + if (!system_supports_generic_auth()) + return -EINVAL; + + pac_generic_keys_to_user(&user_keys, keys); + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &user_keys, 0, -1); +} + +static int pac_generic_keys_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + struct ptrauth_keys *keys = &target->thread.keys_user; + struct user_pac_generic_keys user_keys; + int ret; + + if (!system_supports_generic_auth()) + return -EINVAL; + + pac_generic_keys_to_user(&user_keys, keys); + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &user_keys, 0, -1); + if (ret) + return ret; + pac_generic_keys_from_user(keys, &user_keys); + + return 0; +} +#endif /* CONFIG_CHECKPOINT_RESTORE */ #endif /* CONFIG_ARM64_PTR_AUTH */ enum aarch64_regset { @@ -995,6 +1120,10 @@ enum aarch64_regset { #endif #ifdef CONFIG_ARM64_PTR_AUTH REGSET_PAC_MASK, +#ifdef CONFIG_CHECKPOINT_RESTORE + REGSET_PACA_KEYS, + REGSET_PACG_KEYS, +#endif #endif }; @@ -1074,6 +1203,24 @@ static const struct user_regset aarch64_regsets[] = { .get = pac_mask_get, /* this cannot be set dynamically */ }, +#ifdef CONFIG_CHECKPOINT_RESTORE + [REGSET_PACA_KEYS] = { + .core_note_type = NT_ARM_PACA_KEYS, + .n = sizeof(struct user_pac_address_keys) / sizeof(__uint128_t), + .size = sizeof(__uint128_t), + .align = sizeof(__uint128_t), + .get = pac_address_keys_get, + .set = pac_address_keys_set, + }, + [REGSET_PACG_KEYS] = { + .core_note_type = NT_ARM_PACG_KEYS, + .n = sizeof(struct user_pac_generic_keys) / sizeof(__uint128_t), + .size = sizeof(__uint128_t), + .align = sizeof(__uint128_t), + .get = pac_generic_keys_get, + .set = pac_generic_keys_set, + }, +#endif #endif }; diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index e4d6ddd93567..34c02e4290fe 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -421,6 +421,8 @@ typedef struct elf64_shdr { #define NT_ARM_SYSTEM_CALL 0x404 /* ARM system call number */ #define NT_ARM_SVE 0x405 /* ARM Scalable Vector Extension registers */ #define NT_ARM_PAC_MASK 0x406 /* ARM pointer authentication code masks */ +#define NT_ARM_PACA_KEYS 0x407 /* ARM pointer authentication address keys */ +#define NT_ARM_PACG_KEYS 0x408 /* ARM pointer authentication generic key */ #define NT_ARC_V2 0x600 /* ARCv2 accumulator/extra registers */ #define NT_VMCOREDD 0x700 /* Vmcore Device Dump Note */ #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */ |