gdb/

	* common/linux-ptrace.c: Change __i386__ to __i386__ || __x86_64__.
	(linux_ptrace_test_ret_to_nx): Extend comment for x86_64.  Change
	__i386__ to __i386__ || __x86_64__. Extend code also for __x86_64__.
	Extend code also for PaX support.  Convert all gdb_assert to warning
	calls.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2f6c5c055b6f77345f217f90a94f7af74db9ab18..abe259387442fb7c1b6fcadd02f7ccf642c25605 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2012-09-17  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+       * common/linux-ptrace.c: Change __i386__ to __i386__ || __x86_64__.
+       (linux_ptrace_test_ret_to_nx): Extend comment for x86_64.  Change
+       __i386__ to __i386__ || __x86_64__. Extend code also for __x86_64__.
+       Extend code also for PaX support.  Convert all gdb_assert to warning
+       calls.
+
 2012-09-17  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
        Implement auto-load user conveniences suggested by Doug Evans.

diff --git a/gdb/common/linux-ptrace.c b/gdb/common/linux-ptrace.c
index fdec5d6291c13b329ea921a0321e3cecf6dcb9cb..ae17786eb7a6485c4dc7a3f59db9d5d2391caaf5 100644 (file)
--- a/gdb/common/linux-ptrace.c
+++ b/gdb/common/linux-ptrace.c
@@ -49,7 +49,7 @@ linux_ptrace_attach_warnings (pid_t pid, struct buffer *buffer)
                       (int) pid);
 }
 
-#ifdef __i386__
+#if defined __i386__ || defined __x86_64__
 
 /* Address of the 'ret' instruction in asm code block below.  */
 extern void (linux_ptrace_test_ret_to_nx_instr) (void);
@@ -60,15 +60,17 @@ extern void (linux_ptrace_test_ret_to_nx_instr) (void);
 #include <sys/wait.h>
 #include <stdint.h>
 
-#endif /* __i386__ */
+#endif /* defined __i386__ || defined __x86_64__ */
 
 /* Test broken off-trunk Linux kernel patchset for NX support on i386.  It was
-   removed in Fedora kernel 88fa1f0332d188795ed73d7ac2b1564e11a0b4cd.  */
+   removed in Fedora kernel 88fa1f0332d188795ed73d7ac2b1564e11a0b4cd.
+
+   Test also x86_64 arch for PaX support.  */
 
 static void
 linux_ptrace_test_ret_to_nx (void)
 {
-#ifdef __i386__
+#if defined __i386__ || defined __x86_64__
   pid_t child, got_pid;
   gdb_byte *return_address, *pc;
   long l;
@@ -101,39 +103,105 @@ linux_ptrace_test_ret_to_nx (void)
                 strerror (errno));
       else
        {
+#if defined __i386__
          asm volatile ("pushl %0;"
                        ".globl linux_ptrace_test_ret_to_nx_instr;"
                        "linux_ptrace_test_ret_to_nx_instr:"
                        "ret"
                        : : "r" (return_address) : "%esp", "memory");
+#elif defined __x86_64__
+         asm volatile ("pushq %0;"
+                       ".globl linux_ptrace_test_ret_to_nx_instr;"
+                       "linux_ptrace_test_ret_to_nx_instr:"
+                       "ret"
+                       : : "r" (return_address) : "%rsp", "memory");
+#else
+# error "!__i386__ && !__x86_64__"
+#endif
          gdb_assert_not_reached ("asm block did not terminate");
        }
 
       _exit (1);
     }
 
+  errno = 0;
   got_pid = waitpid (child, &status, 0);
-  gdb_assert (got_pid == child);
-  gdb_assert (WIFSTOPPED (status));
+  if (got_pid != child)
+    {
+      warning (_("linux_ptrace_test_ret_to_nx: waitpid returned %ld: %s"),
+              (long) got_pid, strerror (errno));
+      return;
+    }
+
+  if (WIFSIGNALED (status))
+    {
+      if (WTERMSIG (status) != SIGKILL)
+       warning (_("linux_ptrace_test_ret_to_nx: WTERMSIG %d is not SIGKILL!"),
+                (int) WTERMSIG (status));
+      else
+       warning (_("Cannot call inferior functions, Linux kernel PaX "
+                  "protection forbids return to non-executable pages!"));
+      return;
+    }
+
+  if (!WIFSTOPPED (status))
+    {
+      warning (_("linux_ptrace_test_ret_to_nx: status %d is not WIFSTOPPED!"),
+              status);
+      return;
+    }
 
   /* We may get SIGSEGV due to missing PROT_EXEC of the return_address.  */
-  gdb_assert (WSTOPSIG (status) == SIGTRAP || WSTOPSIG (status) == SIGSEGV);
+  if (WSTOPSIG (status) != SIGTRAP && WSTOPSIG (status) != SIGSEGV)
+    {
+      warning (_("linux_ptrace_test_ret_to_nx: "
+                "WSTOPSIG %d is neither SIGTRAP nor SIGSEGV!"),
+              (int) WSTOPSIG (status));
+      return;
+    }
 
   errno = 0;
+#if defined __i386__
   l = ptrace (PTRACE_PEEKUSER, child, (void *) (uintptr_t) (EIP * 4), NULL);
-  gdb_assert (errno == 0);
+#elif defined __x86_64__
+  l = ptrace (PTRACE_PEEKUSER, child, (void *) (uintptr_t) (RIP * 8), NULL);
+#else
+# error "!__i386__ && !__x86_64__"
+#endif
+  if (errno != 0)
+    {
+      warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_PEEKUSER: %s"),
+              strerror (errno));
+      return;
+    }
   pc = (void *) (uintptr_t) l;
 
   if (ptrace (PTRACE_KILL, child, NULL, NULL) != 0)
-    warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_KILL: %s"),
-            strerror (errno));
+    {
+      warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_KILL: %s"),
+              strerror (errno));
+      return;
+    }
   else
     {
       int kill_status;
 
+      errno = 0;
       got_pid = waitpid (child, &kill_status, 0);
-      gdb_assert (got_pid == child);
-      gdb_assert (WIFSIGNALED (kill_status));
+      if (got_pid != child)
+       {
+         warning (_("linux_ptrace_test_ret_to_nx: "
+                    "PTRACE_KILL waitpid returned %ld: %s"),
+                  (long) got_pid, strerror (errno));
+         return;
+       }
+      if (!WIFSIGNALED (kill_status))
+       {
+         warning (_("linux_ptrace_test_ret_to_nx: "
+                    "PTRACE_KILL status %d is not WIFSIGNALED!"),
+                  status);
+         return;
+       }
     }
 
   /* + 1 is there as x86* stops after the 'int3' instruction.  */
@@ -150,11 +218,14 @@ linux_ptrace_test_ret_to_nx (void)
       return;
     }
 
-  gdb_assert ((void (*) (void)) pc == &linux_ptrace_test_ret_to_nx_instr);
-
-  warning (_("Cannot call inferior functions, you have broken "
-            "Linux kernel i386 NX (non-executable pages) support!"));
-#endif /* __i386__ */
+  if ((void (*) (void)) pc != &linux_ptrace_test_ret_to_nx_instr)
+    warning (_("linux_ptrace_test_ret_to_nx: PC %p is neither near return "
+              "address %p nor is the return instruction %p!"),
+            pc, return_address, &linux_ptrace_test_ret_to_nx_instr);
+  else
+    warning (_("Cannot call inferior functions, you have broken "
+              "Linux kernel i386 NX (non-executable pages) support!"));
+#endif /* defined __i386__ || defined __x86_64__ */
 }
 
 /* Display possible problems on this system.  Display them only once per GDB