patches/glibc/ports-2.10.1/340-dl_execstack-PaX-support.patch
author Johannes Stezenbach <js@sig21.net>
Thu Jul 29 19:47:16 2010 +0200 (2010-07-29)
changeset 2045 fdaa6c7f6dea
permissions -rw-r--r--
cc/gcc: add option to compile against static libstdc++, for gcc-4.4 and newer

Idea and know-how taken from CodeSourcery build script.

Normal build:
$ ldd arm-unknown-linux-uclibcgnueabi-gcc
linux-gate.so.1 => (0xb77f3000)
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0xb76e8000)
libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb75a1000)
libm.so.6 => /lib/i686/cmov/libm.so.6 (0xb757a000)
/lib/ld-linux.so.2 (0xb77f4000)
libgcc_s.so.1 => /lib/libgcc_s.so.1 (0xb755c000)

CC_STATIC_LIBSTDCXX=y:
$ ldd arm-unknown-linux-uclibcgnueabi-gcc
linux-gate.so.1 => (0xb7843000)
libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb76e6000)
/lib/ld-linux.so.2 (0xb7844000)

I made CC_STATIC_LIBSTDCXX default=y since I think
it is always desirable.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
     1 	With latest versions of glibc, a lot of apps failed on a PaX enabled
     2 	system with:
     3 		 cannot enable executable stack as shared object requires: Permission denied
     4 	
     5 	This is due to PaX 'exec-protecting' the stack, and ld.so then trying
     6 	to make the stack executable due to some libraries not containing the
     7 	PT_GNU_STACK section.  Bug #32960.  <azarah@gentoo.org> (12 Nov 2003).
     8 
     9 	Patch also NPTL. Bug #116086. <kevquinn@gentoo.org> (20 Dec 2005).
    10 
    11 diff -durN glibc-2.10.1.orig/nptl/allocatestack.c glibc-2.10.1/nptl/allocatestack.c
    12 --- glibc-2.10.1.orig/nptl/allocatestack.c	2009-01-29 21:34:16.000000000 +0100
    13 +++ glibc-2.10.1/nptl/allocatestack.c	2009-11-13 00:50:33.000000000 +0100
    14 @@ -326,7 +326,8 @@
    15  # error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
    16  #endif
    17    if (mprotect (stack, len, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
    18 -    return errno;
    19 +    if (errno != EACCES) /* PAX is enabled */
    20 +    	return errno;
    21  
    22    return 0;
    23  }
    24 diff -durN glibc-2.10.1.orig/sysdeps/unix/sysv/linux/dl-execstack.c glibc-2.10.1/sysdeps/unix/sysv/linux/dl-execstack.c
    25 --- glibc-2.10.1.orig/sysdeps/unix/sysv/linux/dl-execstack.c	2006-01-08 09:21:15.000000000 +0100
    26 +++ glibc-2.10.1/sysdeps/unix/sysv/linux/dl-execstack.c	2009-11-13 00:50:33.000000000 +0100
    27 @@ -63,7 +63,10 @@
    28        else
    29  # endif
    30  	{
    31 -	  result = errno;
    32 +	  if (errno == EACCES)  /* PAX is enabled */
    33 +	    result = 0;
    34 +	  else
    35 +	    result = errno;
    36  	  goto out;
    37  	}
    38      }
    39 @@ -89,7 +92,12 @@
    40  	page -= size;
    41        else
    42  	{
    43 -	  if (errno != ENOMEM)	/* Unexpected failure mode.  */
    44 +	  if (errno == EACCES)		/* PAX is enabled */
    45 +	    {
    46 +	      result = 0;
    47 +	      goto out;
    48 +	    }
    49 +	  else if (errno != ENOMEM)	/* Unexpected failure mode.  */
    50  	    {
    51  	      result = errno;
    52  	      goto out;
    53 @@ -115,7 +123,12 @@
    54  	page += size;
    55        else
    56  	{
    57 -	  if (errno != ENOMEM)	/* Unexpected failure mode.  */
    58 +	  if (errno == EACCES)		/* PAX is enabled */
    59 +	    {
    60 +	      result = 0;
    61 +	      goto out;
    62 +	    }
    63 +	  else if (errno != ENOMEM)	/* Unexpected failure mode.  */
    64  	    {
    65  	      result = errno;
    66  	      goto out;