// 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 *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(keys); ptrauth_keys_switch(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)); ptrauth_keys_switch(keys); return 0; }