331 lines
8.6 KiB
C
331 lines
8.6 KiB
C
|
// SPDX-License-Identifier: GPL-2.0+
|
||
|
|
/*
|
||
|
|
* Ptrace test for Memory Protection Key registers
|
||
|
|
*
|
||
|
|
* Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
|
||
|
|
* Copyright (C) 2018 IBM Corporation.
|
||
|
|
*/
|
||
|
|
#include "ptrace.h"
|
||
|
|
#include "child.h"
|
||
|
|
|
||
|
|
#ifndef __NR_pkey_alloc
|
||
|
|
#define __NR_pkey_alloc 384
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef __NR_pkey_free
|
||
|
|
#define __NR_pkey_free 385
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef NT_PPC_PKEY
|
||
|
|
#define NT_PPC_PKEY 0x110
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef PKEY_DISABLE_EXECUTE
|
||
|
|
#define PKEY_DISABLE_EXECUTE 0x4
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define AMR_BITS_PER_PKEY 2
|
||
|
|
#define PKEY_REG_BITS (sizeof(u64) * 8)
|
||
|
|
#define pkeyshift(pkey) (PKEY_REG_BITS - ((pkey + 1) * AMR_BITS_PER_PKEY))
|
||
|
|
|
||
|
|
static const char user_read[] = "[User Read (Running)]";
|
||
|
|
static const char user_write[] = "[User Write (Running)]";
|
||
|
|
static const char ptrace_read_running[] = "[Ptrace Read (Running)]";
|
||
|
|
static const char ptrace_write_running[] = "[Ptrace Write (Running)]";
|
||
|
|
|
||
|
|
/* Information shared between the parent and the child. */
|
||
|
|
struct shared_info {
|
||
|
|
struct child_sync child_sync;
|
||
|
|
|
||
|
|
/* AMR value the parent expects to read from the child. */
|
||
|
|
unsigned long amr1;
|
||
|
|
|
||
|
|
/* AMR value the parent is expected to write to the child. */
|
||
|
|
unsigned long amr2;
|
||
|
|
|
||
|
|
/* AMR value that ptrace should refuse to write to the child. */
|
||
|
|
unsigned long invalid_amr;
|
||
|
|
|
||
|
|
/* IAMR value the parent expects to read from the child. */
|
||
|
|
unsigned long expected_iamr;
|
||
|
|
|
||
|
|
/* UAMOR value the parent expects to read from the child. */
|
||
|
|
unsigned long expected_uamor;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* IAMR and UAMOR values that ptrace should refuse to write to the child
|
||
|
|
* (even though they're valid ones) because userspace doesn't have
|
||
|
|
* access to those registers.
|
||
|
|
*/
|
||
|
|
unsigned long invalid_iamr;
|
||
|
|
unsigned long invalid_uamor;
|
||
|
|
};
|
||
|
|
|
||
|
|
static int sys_pkey_alloc(unsigned long flags, unsigned long init_access_rights)
|
||
|
|
{
|
||
|
|
return syscall(__NR_pkey_alloc, flags, init_access_rights);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int child(struct shared_info *info)
|
||
|
|
{
|
||
|
|
unsigned long reg;
|
||
|
|
bool disable_execute = true;
|
||
|
|
int pkey1, pkey2, pkey3;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
/* Wait until parent fills out the initial register values. */
|
||
|
|
ret = wait_parent(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Get some pkeys so that we can change their bits in the AMR. */
|
||
|
|
pkey1 = sys_pkey_alloc(0, PKEY_DISABLE_EXECUTE);
|
||
|
|
if (pkey1 < 0) {
|
||
|
|
pkey1 = sys_pkey_alloc(0, 0);
|
||
|
|
CHILD_FAIL_IF(pkey1 < 0, &info->child_sync);
|
||
|
|
|
||
|
|
disable_execute = false;
|
||
|
|
}
|
||
|
|
|
||
|
|
pkey2 = sys_pkey_alloc(0, 0);
|
||
|
|
CHILD_FAIL_IF(pkey2 < 0, &info->child_sync);
|
||
|
|
|
||
|
|
pkey3 = sys_pkey_alloc(0, 0);
|
||
|
|
CHILD_FAIL_IF(pkey3 < 0, &info->child_sync);
|
||
|
|
|
||
|
|
info->amr1 |= 3ul << pkeyshift(pkey1);
|
||
|
|
info->amr2 |= 3ul << pkeyshift(pkey2);
|
||
|
|
/*
|
||
|
|
* invalid amr value where we try to force write
|
||
|
|
* things which are deined by a uamor setting.
|
||
|
|
*/
|
||
|
|
info->invalid_amr = info->amr2 | (~0x0UL & ~info->expected_uamor);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* if PKEY_DISABLE_EXECUTE succeeded we should update the expected_iamr
|
||
|
|
*/
|
||
|
|
if (disable_execute)
|
||
|
|
info->expected_iamr |= 1ul << pkeyshift(pkey1);
|
||
|
|
else
|
||
|
|
info->expected_iamr &= ~(1ul << pkeyshift(pkey1));
|
||
|
|
|
||
|
|
/*
|
||
|
|
* We allocated pkey2 and pkey 3 above. Clear the IAMR bits.
|
||
|
|
*/
|
||
|
|
info->expected_iamr &= ~(1ul << pkeyshift(pkey2));
|
||
|
|
info->expected_iamr &= ~(1ul << pkeyshift(pkey3));
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Create an IAMR value different from expected value.
|
||
|
|
* Kernel will reject an IAMR and UAMOR change.
|
||
|
|
*/
|
||
|
|
info->invalid_iamr = info->expected_iamr | (1ul << pkeyshift(pkey1) | 1ul << pkeyshift(pkey2));
|
||
|
|
info->invalid_uamor = info->expected_uamor & ~(0x3ul << pkeyshift(pkey1));
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx pkey1: %d pkey2: %d pkey3: %d\n",
|
||
|
|
user_write, info->amr1, pkey1, pkey2, pkey3);
|
||
|
|
|
||
|
|
set_amr(info->amr1);
|
||
|
|
|
||
|
|
/* Wait for parent to read our AMR value and write a new one. */
|
||
|
|
ret = prod_parent(&info->child_sync);
|
||
|
|
CHILD_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_parent(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
reg = mfspr(SPRN_AMR);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx\n", user_read, reg);
|
||
|
|
|
||
|
|
CHILD_FAIL_IF(reg != info->amr2, &info->child_sync);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Wait for parent to try to write an invalid AMR value.
|
||
|
|
*/
|
||
|
|
ret = prod_parent(&info->child_sync);
|
||
|
|
CHILD_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_parent(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
reg = mfspr(SPRN_AMR);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx\n", user_read, reg);
|
||
|
|
|
||
|
|
CHILD_FAIL_IF(reg != info->amr2, &info->child_sync);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Wait for parent to try to write an IAMR and a UAMOR value. We can't
|
||
|
|
* verify them, but we can verify that the AMR didn't change.
|
||
|
|
*/
|
||
|
|
ret = prod_parent(&info->child_sync);
|
||
|
|
CHILD_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_parent(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
reg = mfspr(SPRN_AMR);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx\n", user_read, reg);
|
||
|
|
|
||
|
|
CHILD_FAIL_IF(reg != info->amr2, &info->child_sync);
|
||
|
|
|
||
|
|
/* Now let parent now that we are finished. */
|
||
|
|
|
||
|
|
ret = prod_parent(&info->child_sync);
|
||
|
|
CHILD_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
return TEST_PASS;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int parent(struct shared_info *info, pid_t pid)
|
||
|
|
{
|
||
|
|
unsigned long regs[3];
|
||
|
|
int ret, status;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Get the initial values for AMR, IAMR and UAMOR and communicate them
|
||
|
|
* to the child.
|
||
|
|
*/
|
||
|
|
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
|
||
|
|
PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
info->amr1 = info->amr2 = regs[0];
|
||
|
|
info->expected_iamr = regs[1];
|
||
|
|
info->expected_uamor = regs[2];
|
||
|
|
|
||
|
|
/* Wake up child so that it can set itself up. */
|
||
|
|
ret = prod_child(&info->child_sync);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_child(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Verify that we can read the pkey registers from the child. */
|
||
|
|
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx IAMR: %016lx UAMOR: %016lx\n",
|
||
|
|
ptrace_read_running, regs[0], regs[1], regs[2]);
|
||
|
|
|
||
|
|
PARENT_FAIL_IF(regs[0] != info->amr1, &info->child_sync);
|
||
|
|
PARENT_FAIL_IF(regs[1] != info->expected_iamr, &info->child_sync);
|
||
|
|
PARENT_FAIL_IF(regs[2] != info->expected_uamor, &info->child_sync);
|
||
|
|
|
||
|
|
/* Write valid AMR value in child. */
|
||
|
|
ret = ptrace_write_regs(pid, NT_PPC_PKEY, &info->amr2, 1);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx\n", ptrace_write_running, info->amr2);
|
||
|
|
|
||
|
|
/* Wake up child so that it can verify it changed. */
|
||
|
|
ret = prod_child(&info->child_sync);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_child(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Write invalid AMR value in child. */
|
||
|
|
ret = ptrace_write_regs(pid, NT_PPC_PKEY, &info->invalid_amr, 1);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx\n", ptrace_write_running, info->invalid_amr);
|
||
|
|
|
||
|
|
/* Wake up child so that it can verify it didn't change. */
|
||
|
|
ret = prod_child(&info->child_sync);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait_child(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Try to write to IAMR. */
|
||
|
|
regs[0] = info->amr1;
|
||
|
|
regs[1] = info->invalid_iamr;
|
||
|
|
ret = ptrace_write_regs(pid, NT_PPC_PKEY, regs, 2);
|
||
|
|
PARENT_FAIL_IF(!ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx IAMR: %016lx\n",
|
||
|
|
ptrace_write_running, regs[0], regs[1]);
|
||
|
|
|
||
|
|
/* Try to write to IAMR and UAMOR. */
|
||
|
|
regs[2] = info->invalid_uamor;
|
||
|
|
ret = ptrace_write_regs(pid, NT_PPC_PKEY, regs, 3);
|
||
|
|
PARENT_FAIL_IF(!ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx IAMR: %016lx UAMOR: %016lx\n",
|
||
|
|
ptrace_write_running, regs[0], regs[1], regs[2]);
|
||
|
|
|
||
|
|
/* Verify that all registers still have their expected values. */
|
||
|
|
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
printf("%-30s AMR: %016lx IAMR: %016lx UAMOR: %016lx\n",
|
||
|
|
ptrace_read_running, regs[0], regs[1], regs[2]);
|
||
|
|
|
||
|
|
PARENT_FAIL_IF(regs[0] != info->amr2, &info->child_sync);
|
||
|
|
PARENT_FAIL_IF(regs[1] != info->expected_iamr, &info->child_sync);
|
||
|
|
PARENT_FAIL_IF(regs[2] != info->expected_uamor, &info->child_sync);
|
||
|
|
|
||
|
|
/* Wake up child so that it can verify AMR didn't change and wrap up. */
|
||
|
|
ret = prod_child(&info->child_sync);
|
||
|
|
PARENT_FAIL_IF(ret, &info->child_sync);
|
||
|
|
|
||
|
|
ret = wait(&status);
|
||
|
|
if (ret != pid) {
|
||
|
|
printf("Child's exit status not captured\n");
|
||
|
|
ret = TEST_PASS;
|
||
|
|
} else if (!WIFEXITED(status)) {
|
||
|
|
printf("Child exited abnormally\n");
|
||
|
|
ret = TEST_FAIL;
|
||
|
|
} else
|
||
|
|
ret = WEXITSTATUS(status) ? TEST_FAIL : TEST_PASS;
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ptrace_pkey(void)
|
||
|
|
{
|
||
|
|
struct shared_info *info;
|
||
|
|
int shm_id;
|
||
|
|
int ret;
|
||
|
|
pid_t pid;
|
||
|
|
|
||
|
|
shm_id = shmget(IPC_PRIVATE, sizeof(*info), 0777 | IPC_CREAT);
|
||
|
|
info = shmat(shm_id, NULL, 0);
|
||
|
|
|
||
|
|
ret = init_child_sync(&info->child_sync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
pid = fork();
|
||
|
|
if (pid < 0) {
|
||
|
|
perror("fork() failed");
|
||
|
|
ret = TEST_FAIL;
|
||
|
|
} else if (pid == 0)
|
||
|
|
ret = child(info);
|
||
|
|
else
|
||
|
|
ret = parent(info, pid);
|
||
|
|
|
||
|
|
shmdt(info);
|
||
|
|
|
||
|
|
if (pid) {
|
||
|
|
destroy_child_sync(&info->child_sync);
|
||
|
|
shmctl(shm_id, IPC_RMID, NULL);
|
||
|
|
}
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
int main(int argc, char *argv[])
|
||
|
|
{
|
||
|
|
return test_harness(ptrace_pkey, "ptrace_pkey");
|
||
|
|
}
|