| // SPDX-License-Identifier: GPL-2.0 |
| |
| #include <linux/errno.h> |
| #include <linux/prctl.h> |
| #include <linux/random.h> |
| #include <linux/sched.h> |
| #include <asm/cpufeature.h> |
| #include <asm/pointer_auth.h> |
| |
| int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg) |
| { |
| struct ptrauth_keys_user *keys = &tsk->thread.keys_user; |
| unsigned long addr_key_mask = PR_PAC_APIAKEY | PR_PAC_APIBKEY | |
| PR_PAC_APDAKEY | PR_PAC_APDBKEY; |
| unsigned long key_mask = addr_key_mask | PR_PAC_APGAKEY; |
| |
| if (!system_supports_address_auth() && !system_supports_generic_auth()) |
| return -EINVAL; |
| |
| if (!arg) { |
| ptrauth_keys_init_user(keys); |
| return 0; |
| } |
| |
| if (arg & ~key_mask) |
| return -EINVAL; |
| |
| if (((arg & addr_key_mask) && !system_supports_address_auth()) || |
| ((arg & PR_PAC_APGAKEY) && !system_supports_generic_auth())) |
| return -EINVAL; |
| |
| if (arg & PR_PAC_APIAKEY) |
| get_random_bytes(&keys->apia, sizeof(keys->apia)); |
| if (arg & PR_PAC_APIBKEY) |
| get_random_bytes(&keys->apib, sizeof(keys->apib)); |
| if (arg & PR_PAC_APDAKEY) |
| get_random_bytes(&keys->apda, sizeof(keys->apda)); |
| if (arg & PR_PAC_APDBKEY) |
| get_random_bytes(&keys->apdb, sizeof(keys->apdb)); |
| if (arg & PR_PAC_APGAKEY) |
| get_random_bytes(&keys->apga, sizeof(keys->apga)); |
| |
| return 0; |
| } |
