diff options
Diffstat (limited to 'arch/arm64/kernel/pointer_auth.c')
-rw-r--r-- | arch/arm64/kernel/pointer_auth.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/arm64/kernel/pointer_auth.c b/arch/arm64/kernel/pointer_auth.c new file mode 100644 index 000000000..adb955fd9 --- /dev/null +++ b/arch/arm64/kernel/pointer_auth.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/compat.h> +#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 (is_compat_thread(task_thread_info(tsk))) + 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; +} |