mirror of
https://github.com/torvalds/linux.git
synced 2024-12-30 14:52:05 +00:00
84931327a8
We don't need to get at the per-thread keys from assembly at all, so they can live alongside the rest of the per-thread register state in thread_struct instead of thread_info. This will also allow straighforward whitelisting of the keys for hardened usercopy should we expose them via a ptrace request later on. Signed-off-by: Will Deacon <will.deacon@arm.com>
48 lines
1.3 KiB
C
48 lines
1.3 KiB
C
// 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;
|
|
}
|