[src/trunk]: src/tests/lib/libc/sys Add new ATF tests in t_ptrace_wait*

[kamil <kamil%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/06515757e07a
branches:  trunk
changeset: 848232:06515757e07a
user:      kamil <kamil%NetBSD.org@localhost>
date:      Tue Jan 21 16:46:07 2020 +0000

description:
Add new ATF tests in t_ptrace_wait*

New tests:
 - access_regs_set_unaligned_pc_0x1
 - access_regs_set_unaligned_pc_0x3
 - access_regs_set_unaligned_pc_0x7

The purpose of these tests is check whether unaligned PC can panic the
kernel. If there is a panic it is fine to return EINVAL on PT_SETREGS.
New tests check respectively pc |= 0x1, pc |= 0x3 and pc |= 0x7.

Inspired by https://marc.info/?l=openbsd-bugs&m=107558043319084&w=2

While there fix access_regs6 to really test PT_SETREGS.

diffstat:

 tests/lib/libc/sys/t_ptrace_wait.c |  60 +++++++++++++++++++++++++++++++------
 1 files changed, 49 insertions(+), 11 deletions(-)

diffs (111 lines):

diff -r 2d9d746748ce -r 06515757e07a tests/lib/libc/sys/t_ptrace_wait.c
--- a/tests/lib/libc/sys/t_ptrace_wait.c        Tue Jan 21 16:27:53 2020 +0000
+++ b/tests/lib/libc/sys/t_ptrace_wait.c        Tue Jan 21 16:46:07 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_ptrace_wait.c,v 1.146 2020/01/08 17:22:40 mgorny Exp $       */
+/*     $NetBSD: t_ptrace_wait.c,v 1.147 2020/01/21 16:46:07 kamil Exp $        */
 
 /*-
  * Copyright (c) 2016, 2017, 2018, 2019 The NetBSD Foundation, Inc.
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: t_ptrace_wait.c,v 1.146 2020/01/08 17:22:40 mgorny Exp $");
+__RCSID("$NetBSD: t_ptrace_wait.c,v 1.147 2020/01/21 16:46:07 kamil Exp $");
 
 #define __LEGACY_PT_LWPINFO
 
@@ -4439,9 +4439,22 @@
                } else if (strcmp(aux, "pc") == 0) {
                        rgstr = PTRACE_REG_PC(&gpr);
                        DPRINTF("Retrieved %" PRIxREGISTER "\n", rgstr);
-               } else if (strcmp(aux, "set_pc") == 0) {
+               } else if (strstr(aux, "set_pc") != NULL) {
                        rgstr = PTRACE_REG_PC(&gpr);
+                       DPRINTF("Retrieved PC %" PRIxREGISTER "\n", rgstr);
+                       if (strstr(aux, "0x1") != NULL) {
+                               rgstr |= 0x1;
+                       } else if (strstr(aux, "0x3") != NULL) {
+                               rgstr |= 0x3;
+                       } else if (strstr(aux, "0x7") != NULL) {
+                               rgstr |= 0x7;
+                       }
+                       DPRINTF("Set PC %" PRIxREGISTER "\n", rgstr);
                        PTRACE_REG_SET_PC(&gpr, rgstr);
+                       if (strcmp(aux, "set_pc") != 0) {
+                               /* This call can fail with EINVAL or similar. */
+                               ptrace(PT_SETREGS, child, &gpr, 0);
+                       }
                } else if (strcmp(aux, "sp") == 0) {
                        rgstr = PTRACE_REG_SP(&gpr);
                        DPRINTF("Retrieved %" PRIxREGISTER "\n", rgstr);
@@ -4451,7 +4464,7 @@
                } else if (strcmp(aux, "setregs") == 0) {
                        DPRINTF("Call SETREGS for the child process\n");
                        SYSCALL_REQUIRE(
-                           ptrace(PT_GETREGS, child, &gpr, 0) != -1);
+                           ptrace(PT_SETREGS, child, &gpr, 0) != -1);
                }
        }
 #endif
@@ -4475,13 +4488,31 @@
            "without signal to be sent\n");
        SYSCALL_REQUIRE(ptrace(PT_CONTINUE, child, (void *)1, 0) != -1);
 
-       DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
-       TWAIT_REQUIRE_SUCCESS(wpid = TWAIT_GENERIC(child, &status, 0), child);
-
-       validate_status_exited(status, exitval);
-
-       DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
-       TWAIT_REQUIRE_FAILURE(ECHILD, wpid = TWAIT_GENERIC(child, &status, 0));
+       if (strstr(aux, "unaligned") != NULL) {
+               DPRINTF("Before resuming the child process where it left off "
+                   "and without signal to be sent\n");
+               SYSCALL_REQUIRE(ptrace(PT_KILL, child, NULL, 0) != -1);
+
+               DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
+               TWAIT_REQUIRE_SUCCESS(wpid = TWAIT_GENERIC(child, &status, 0),
+                   child);
+
+               validate_status_signaled(status, SIGKILL, 0);
+
+               DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
+               TWAIT_REQUIRE_FAILURE(ECHILD,
+                   wpid = TWAIT_GENERIC(child, &status, 0));
+       } else {
+               DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
+               TWAIT_REQUIRE_SUCCESS(
+                   wpid = TWAIT_GENERIC(child, &status, 0), child);
+
+               validate_status_exited(status, exitval);
+
+               DPRINTF("Before calling %s() for the child\n", TWAIT_FNAME);
+               TWAIT_REQUIRE_FAILURE(ECHILD,
+                   wpid = TWAIT_GENERIC(child, &status, 0));
+       }
 }
 
 #define ACCESS_REGS(test, regset, aux)                                 \
@@ -4506,6 +4537,9 @@
 ACCESS_REGS(access_regs4, "regs", "sp")
 ACCESS_REGS(access_regs5, "regs", "intrv")
 ACCESS_REGS(access_regs6, "regs", "setregs")
+ACCESS_REGS(access_regs_set_unaligned_pc_0x1, "regs", "set_pc+unaligned+0x1")
+ACCESS_REGS(access_regs_set_unaligned_pc_0x3, "regs", "set_pc+unaligned+0x3")
+ACCESS_REGS(access_regs_set_unaligned_pc_0x7, "regs", "set_pc+unaligned+0x7")
 #endif
 #if defined(HAVE_FPREGS)
 ACCESS_REGS(access_fpregs1, "fpregs", "getfpregs")
@@ -8415,6 +8449,10 @@
        ATF_TP_ADD_TC_HAVE_GPREGS(tp, access_regs5);
        ATF_TP_ADD_TC_HAVE_GPREGS(tp, access_regs6);
 
+       ATF_TP_ADD_TC(tp, access_regs_set_unaligned_pc_0x1);
+       ATF_TP_ADD_TC(tp, access_regs_set_unaligned_pc_0x3);
+       ATF_TP_ADD_TC(tp, access_regs_set_unaligned_pc_0x7);
+
        ATF_TP_ADD_TC_HAVE_FPREGS(tp, access_fpregs1);
        ATF_TP_ADD_TC_HAVE_FPREGS(tp, access_fpregs2);