diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c | 57 |
1 files changed, 28 insertions, 29 deletions
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c b/tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c index bdbbbe8431e0..bc454f899124 100644 --- a/tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c +++ b/tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c @@ -44,7 +44,7 @@ struct shared_info { unsigned long amr2; /* AMR value that ptrace should refuse to write to the child. */ - unsigned long amr3; + unsigned long invalid_amr; /* IAMR value the parent expects to read from the child. */ unsigned long expected_iamr; @@ -57,8 +57,8 @@ struct shared_info { * (even though they're valid ones) because userspace doesn't have * access to those registers. */ - unsigned long new_iamr; - unsigned long new_uamor; + unsigned long invalid_iamr; + unsigned long invalid_uamor; }; static int sys_pkey_alloc(unsigned long flags, unsigned long init_access_rights) @@ -66,11 +66,6 @@ static int sys_pkey_alloc(unsigned long flags, unsigned long init_access_rights) return syscall(__NR_pkey_alloc, flags, init_access_rights); } -static int sys_pkey_free(int pkey) -{ - return syscall(__NR_pkey_free, pkey); -} - static int child(struct shared_info *info) { unsigned long reg; @@ -100,33 +95,37 @@ static int child(struct shared_info *info) info->amr1 |= 3ul << pkeyshift(pkey1); info->amr2 |= 3ul << pkeyshift(pkey2); - info->amr3 |= info->amr2 | 3ul << pkeyshift(pkey3); + /* + * 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)); - info->expected_iamr &= ~(1ul << pkeyshift(pkey2) | 1ul << pkeyshift(pkey3)); - - info->expected_uamor |= 3ul << pkeyshift(pkey1) | - 3ul << pkeyshift(pkey2); - info->new_iamr |= 1ul << pkeyshift(pkey1) | 1ul << pkeyshift(pkey2); - info->new_uamor |= 3ul << 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)); /* - * We won't use pkey3. We just want a plausible but invalid key to test - * whether ptrace will let us write to AMR bits we are not supposed to. - * - * This also tests whether the kernel restores the UAMOR permissions - * after a key is freed. + * Create an IAMR value different from expected value. + * Kernel will reject an IAMR and UAMOR change. */ - sys_pkey_free(pkey3); + 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); - mtspr(SPRN_AMR, info->amr1); + set_amr(info->amr1); /* Wait for parent to read our AMR value and write a new one. */ ret = prod_parent(&info->child_sync); @@ -196,9 +195,9 @@ static int parent(struct shared_info *info, pid_t pid) PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync); PARENT_FAIL_IF(ret, &info->child_sync); - info->amr1 = info->amr2 = info->amr3 = regs[0]; - info->expected_iamr = info->new_iamr = regs[1]; - info->expected_uamor = info->new_uamor = regs[2]; + 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); @@ -234,10 +233,10 @@ static int parent(struct shared_info *info, pid_t pid) return ret; /* Write invalid AMR value in child. */ - ret = ptrace_write_regs(pid, NT_PPC_PKEY, &info->amr3, 1); + 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->amr3); + 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); @@ -249,7 +248,7 @@ static int parent(struct shared_info *info, pid_t pid) /* Try to write to IAMR. */ regs[0] = info->amr1; - regs[1] = info->new_iamr; + regs[1] = info->invalid_iamr; ret = ptrace_write_regs(pid, NT_PPC_PKEY, regs, 2); PARENT_FAIL_IF(!ret, &info->child_sync); @@ -257,7 +256,7 @@ static int parent(struct shared_info *info, pid_t pid) ptrace_write_running, regs[0], regs[1]); /* Try to write to IAMR and UAMOR. */ - regs[2] = info->new_uamor; + regs[2] = info->invalid_uamor; ret = ptrace_write_regs(pid, NT_PPC_PKEY, regs, 3); PARENT_FAIL_IF(!ret, &info->child_sync); |