Use mmap for allocation of buffers used for __abort_msg

ChangeLog

@@ -1,5 +1,23 @@
+2011-05-15  Ulrich Drepper  <drepper@gmail.com>
+
+	[BZ #11901]
+	* include/stdlib.h: Move include protection to the right place.
+	Define abort_msg_s.  Declare __abort_msg with it.
+	* stdlib/abort.c (__abort_msg): Adjust type.
+	* assert/assert.c (__assert_fail_base): New function.  Majority
+	of code from __assert_fail.  Allocate memory for __abort_msg with
+	mmap.
+	(__assert_fail): Now call __assert_fail_base.
+	* assert/assert-perr.c: Remove bulk of implementation.  Use
+	__assert_fail_base.
+	* include/assert.hL Declare __assert_fail_base.
+	* sysdeps/posix/libc_fatal.c: Allocate memory for __abort_msg with
+	mmap.
+	* sysdeps/unix/sysv/linux/libc_fatal.c: Likewise.
+
 2011-05-14  Ulrich Drepper  <drepper@gmail.com>
 
+	[BZ #11952]
 	[BZ #12453]
 	* elf/dl-open.c (dl_open_worker): Delay calls to _dl_update_slotinfo
 	until all modules are registered in the DTV.

NEWS

@@ -9,12 +9,12 @@ Version 2.14
 
 * The following bugs are resolved with this release:
 
-  386, 11257, 11258, 11487, 11532, 11578, 11653, 11668, 11724, 11945, 11947,
+  386, 11257, 11258, 11487, 11532, 11578, 11653, 11668, 11724, 11901, 11945,
-  11952, 12052, 12083, 12158, 12178, 12200, 12346, 12393, 12420, 12432,
+  11947, 11952, 12052, 12083, 12158, 12178, 12200, 12346, 12393, 12420,
-  12445, 12449, 12453, 12454, 12460, 12469, 12489, 12509, 12510, 12511,
+  12432, 12445, 12449, 12453, 12454, 12460, 12469, 12489, 12509, 12510,
-  12518, 12527, 12541, 12545, 12551, 12582, 12583, 12587, 12597, 12601,
+  12511, 12518, 12527, 12541, 12545, 12551, 12582, 12583, 12587, 12597,
-  12611, 12625, 12626, 12631, 12650, 12653, 12655, 12660, 12681, 12685,
+  12601, 12611, 12625, 12626, 12631, 12650, 12653, 12655, 12660, 12681,
-  12711, 12713, 12714, 12717, 12723, 12724, 12734, 12738
+  12685, 12711, 12713, 12714, 12717, 12723, 12724, 12734, 12738
 
 * The RPC implementation in libc is obsoleted.  Old programs keep working
   but new programs cannot be linked with the routines in libc anymore.

assert/assert-perr.c

@@ -1,4 +1,5 @@
-/* Copyright (C) 1994-1998,2001,2002,2005,2009 Free Software Foundation, Inc.
+/* Copyright (C) 1994-1998,2001,2002,2005,2009,2011
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -17,66 +18,23 @@
    02111-1307 USA.  */
 
 #include <assert.h>
-#include <atomic.h>
 #include <libintl.h>
-#include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
-#include <sysdep.h>
-#include <unistd.h>
 
 
-extern const char *__progname;
-
-#ifdef USE_IN_LIBIO
-# include <wchar.h>
-# include <libio/iolibio.h>
-# define fflush(s) INTUSE(_IO_fflush) (s)
-#endif
-
 /* This function, when passed an error number, a filename, and a line
    number, prints a message on the standard error stream of the form:
-   	a.c:10: foobar: Unexpected error: Computer bought the farm
+	a.c:10: foobar: Unexpected error: Computer bought the farm
    It then aborts program execution via a call to `abort'.  */
-
-#ifdef FATAL_PREPARE_INCLUDE
-# include FATAL_PREPARE_INCLUDE
-#endif
-
 void
 __assert_perror_fail (int errnum,
 		      const char *file, unsigned int line,
 		      const char *function)
 {
   char errbuf[1024];
-  char *buf;
 
-#ifdef FATAL_PREPARE
+  char *e = __strerror_r (errnum, errbuf, sizeof errbuf);
-  FATAL_PREPARE;
+  __assert_fail_base (_("%s%s%s:%u: %s%sUnexpected error: %s.\n"),
-#endif
+		      e, file, line, function);
-
-  if (__asprintf (&buf, _("%s%s%s:%u: %s%sUnexpected error: %s.\n"),
-		  __progname, __progname[0] ? ": " : "",
-		  file, line,
-		  function ? function : "", function ? ": " : "",
-		  __strerror_r (errnum, errbuf, sizeof errbuf)) >= 0)
-    {
-      /* Print the message.  */
-      (void) __fxprintf (NULL, "%s", buf);
-      (void) fflush (stderr);
-
-      /* We have to free the old buffer since the application might
-	 catch the SIGABRT signal.  */
-      char *old = atomic_exchange_acq (&__abort_msg, buf);
-      free (old);
-    }
-  else
-    {
-      /* At least print a minimal message.  */
-      static const char errstr[] = "Unexpected error.\n";
-      __libc_write (STDERR_FILENO, errstr, sizeof (errstr) - 1);
-    }
-
-  abort ();
 }
 libc_hidden_def (__assert_perror_fail)

assert/assert.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 1991,1994-1996,1998,2001,2002,2005,2009
+/* Copyright (C) 1991,1994-1996,1998,2001,2002,2005,2009,2011
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -19,11 +19,13 @@
 
 #include <assert.h>
 #include <atomic.h>
+#include <ldsodefs.h>
 #include <libintl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sysdep.h>
 #include <unistd.h>
+#include <sys/mman.h>
 
 
 extern const char *__progname;
@@ -37,7 +39,7 @@ extern const char *__progname;
 /* This function, when passed a string containing an asserted
    expression, a filename, and a line number, prints a message
    on the standard error stream of the form:
-   	a.c:10: foobar: Assertion `a == b' failed.
+	a.c:10: foobar: Assertion `a == b' failed.
    It then aborts program execution via a call to `abort'.  */
 
 #ifdef FATAL_PREPARE_INCLUDE
@@ -45,31 +47,44 @@ extern const char *__progname;
 #endif
 
 
-#undef __assert_fail
 void
-__assert_fail (const char *assertion, const char *file, unsigned int line,
+__assert_fail_base (const char *fmt, const char *assertion, const char *file,
-	       const char *function)
+		    unsigned int line, const char *function)
 {
-  char *buf;
+  char *str;
 
 #ifdef FATAL_PREPARE
   FATAL_PREPARE;
 #endif
 
-  if (__asprintf (&buf, _("%s%s%s:%u: %s%sAssertion `%s' failed.\n"),
+  int total;
+  if (__asprintf (&str, fmt,
 		  __progname, __progname[0] ? ": " : "",
 		  file, line,
 		  function ? function : "", function ? ": " : "",
-		  assertion) >= 0)
+		  assertion, &total) >= 0)
     {
       /* Print the message.  */
-      (void) __fxprintf (NULL, "%s", buf);
+      (void) __fxprintf (NULL, "%s", str);
       (void) fflush (stderr);
 
-      /* We have to free the old buffer since the application might
+      total = (total + 1 + GLRO(dl_pagesize) - 1) & ~(GLRO(dl_pagesize) - 1);
-	 catch the SIGABRT signal.  */
+      struct abort_msg_s *buf = __mmap (NULL, total, PROT_READ | PROT_WRITE,
-      char *old = atomic_exchange_acq (&__abort_msg, buf);
+					MAP_ANON | MAP_PRIVATE, -1, 0);
-      free (old);
+      if (__builtin_expect (buf != MAP_FAILED, 1))
+	{
+	  buf->size = total;
+	  strcpy (buf->msg, str);
+
+	  /* We have to free the old buffer since the application might
+	     catch the SIGABRT signal.  */
+	  struct abort_msg_s *old = atomic_exchange_acq (&__abort_msg, buf);
+
+	  if (old != NULL)
+	    __munmap (old, old->size);
+	}
+
+      free (str);
     }
   else
     {
@@ -80,4 +95,14 @@ __assert_fail (const char *assertion, const char *file, unsigned int line,
 
   abort ();
 }
+
+
+#undef __assert_fail
+void
+__assert_fail (const char *assertion, const char *file, unsigned int line,
+	       const char *function)
+{
+  __assert_fail_base (_("%s%s%s:%u: %s%sAssertion `%s' failed.\n%n"),
+		      assertion, file, line, function);
+}
 hidden_def(__assert_fail)

include/assert.h

@@ -5,7 +5,7 @@
    so it has to be repeated here.  */
 extern void __assert_fail (__const char *__assertion, __const char *__file,
 			   unsigned int __line, __const char *__function)
-  __THROW __attribute__ ((__noreturn__));
+     __THROW __attribute__ ((__noreturn__));
 
 /* Likewise, but prints the error text for ERRNUM.  */
 extern void __assert_perror_fail (int __errnum, __const char *__file,
@@ -13,6 +13,12 @@ extern void __assert_perror_fail (int __errnum, __const char *__file,
 				  __const char *__function)
      __THROW __attribute__ ((__noreturn__));
 
+/* The real implementation of the two functions above.  */
+extern void __assert_fail_base (const char *fmt, const char *assertion,
+				const char *file, unsigned int line,
+				const char *function)
+     __THROW  __attribute__ ((__noreturn__));
+
 #if !defined NOT_IN_libc || defined IS_IN_rtld
 hidden_proto (__assert_fail)
 hidden_proto (__assert_perror_fail)

include/stdlib.h

@@ -223,16 +223,21 @@ extern int __qfcvt_r (long double __value, int __ndigit,
 # define __cxa_atexit(func, arg, d) INTUSE(__cxa_atexit) (func, arg, d)
 # endif
 
-#endif
-
 extern void *__default_morecore (ptrdiff_t) __THROW;
 libc_hidden_proto (__default_morecore)
 
-extern char *__abort_msg;
+struct abort_msg_s
+{
+  unsigned int size;
+  char msg[0];
+};
+extern struct abort_msg_s *__abort_msg;
 libc_hidden_proto (__abort_msg)
 
 __END_DECLS
 
+#endif
+
 #undef __Need_M_And_C
 
 #endif  /* include/stdlib.h */

stdlib/abort.c

@@ -1,4 +1,5 @@
-/* Copyright (C) 1991,93,1995-1998,2001,02,2009 Free Software Foundation, Inc.
+/* Copyright (C) 1991,1993,1995-1998,2001,2002,2009,2011
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -37,7 +38,7 @@
 #endif
 
 /* Exported variable to locate abort message in core files etc.  */
-char *__abort_msg __attribute__ ((nocommon));
+struct abort_msg_s *__abort_msg __attribute__ ((nocommon));
 libc_hidden_def (__abort_msg)
 
 /* We must avoid to run in circles.  Therefore we remember how far we

sysdeps/posix/libc_fatal.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 1993-1995,1997,2000,2004,2005,2009
+/* Copyright (C) 1993-1995,1997,2000,2004,2005,2009,2011
 	Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -20,6 +20,7 @@
 #include <atomic.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <ldsodefs.h>
 #include <paths.h>
 #include <stdarg.h>
 #include <stdbool.h>
@@ -125,18 +126,28 @@ __libc_message (int do_abort, const char *fmt, ...)
       if (TEMP_FAILURE_RETRY (__writev (fd, iov, nlist)) == total)
 	written = true;
 
-      char *buf = do_abort ? malloc (total + 1) : NULL;
+      if (do_abort)
-      if (buf != NULL)
 	{
-	  char *wp = buf;
+	  total = ((total + 1 + GLRO(dl_pagesize) - 1)
-	  for (int cnt = 0; cnt < nlist; ++cnt)
+		   & ~(GLRO(dl_pagesize) - 1));
-	    wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	  struct abort_msg_s *buf = __mmap (NULL, total,
-	  *wp = '\0';
+					    PROT_READ | PROT_WRITE,
+					    MAP_ANON | MAP_PRIVATE, -1, 0);
+	  if (buf != MAP_FAILED)
+	    {
+	      buf->size = total;
+	      char *wp = buf->msg;
+	      for (int cnt = 0; cnt < nlist; ++cnt)
+		wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	      *wp = '\0';
 
-	  /* We have to free the old buffer since the application might
+	      /* We have to free the old buffer since the application might
-	     catch the SIGABRT signal.  */
+		 catch the SIGABRT signal.  */
-	  char *old = atomic_exchange_acq (&__abort_msg, buf);
+	      struct abort_msg_s *old = atomic_exchange_acq (&__abort_msg,
-	  free (old);
+							     buf);
+	      if (old != NULL)
+		__munmap (old, old->size);
+	    }
 	}
     }
 

sysdeps/unix/sysv/linux/libc_fatal.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 1993-1995,1997,2000,2002-2005,2009
+/* Copyright (C) 1993-1995,1997,2000,2002-2005,2009,2011
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -20,6 +20,7 @@
 #include <atomic.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <ldsodefs.h>
 #include <paths.h>
 #include <stdarg.h>
 #include <stdbool.h>
@@ -28,6 +29,7 @@
 #include <string.h>
 #include <sysdep.h>
 #include <unistd.h>
+#include <sys/mman.h>
 #include <sys/syslog.h>
 #include <execinfo.h>
 
@@ -134,18 +136,28 @@ __libc_message (int do_abort, const char *fmt, ...)
       if (cnt == total)
 	written = true;
 
-      char *buf = do_abort ? malloc (total + 1) : NULL;
+      if (do_abort)
-      if (buf != NULL)
 	{
-	  char *wp = buf;
+	  total = ((total + 1 + GLRO(dl_pagesize) - 1)
-	  for (int cnt = 0; cnt < nlist; ++cnt)
+		   & ~(GLRO(dl_pagesize) - 1));
-	    wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	  struct abort_msg_s *buf = __mmap (NULL, total,
-	  *wp = '\0';
+					    PROT_READ | PROT_WRITE,
+					    MAP_ANON | MAP_PRIVATE, -1, 0);
+	  if (__builtin_expect (buf != MAP_FAILED, 1))
+	    {
+	      buf->size = total;
+	      char *wp = buf->msg;
+	      for (int cnt = 0; cnt < nlist; ++cnt)
+		wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	      *wp = '\0';
 
-	  /* We have to free the old buffer since the application might
+	      /* We have to free the old buffer since the application might
-	     catch the SIGABRT signal.  */
+		 catch the SIGABRT signal.  */
-	  char *old = atomic_exchange_acq (&__abort_msg, buf);
+	      struct abort_msg_s *old = atomic_exchange_acq (&__abort_msg,
-	  free (old);
+							     buf);
+	      if (old != NULL)
+		__munmap (old, old->size);
+	    }
 	}
     }