diff options
| author | Eric Andersen <andersen@codepoet.org> | 2004-01-02 23:34:13 +0000 |
|---|---|---|
| committer | Eric Andersen <andersen@codepoet.org> | 2004-01-02 23:34:13 +0000 |
| commit | fb84603f8c45fdafdaa750490785fc1b15541386 (patch) | |
| tree | 257c50f56dfb4d90e775b83a915ae21d9f39bb04 /libc/sysdeps/linux/i386/crt0.S | |
| parent | cadff3f10e8f20f8db0e2878abf90fb16eba797a (diff) | |
Peter S. Mazinger writes:
Hello Erik!
I have made some cosmetical changes to the files, removed the added
SCRT=-fPIC option from building the crt0.S file (but it is a requirement
to build them with -fPIC), and changed some comments. I have left the
ldso.c patch with PIE_SUPPORT ifdefs, but consider applying it w/o them
(see some earlier comment from PaX Team on this issue, as it is considered
a bug). To have it work correctly, you'll also need removing
COMPLETELY_PIC.
One thing is missing: PIE_SUPPORT should be usable only for i386 (for
now).
Also added the support for propolice protection (that works for me and
catches memcpy/strcpy attacks (but needs a special gcc version).
Thanks, Peter
Diffstat (limited to 'libc/sysdeps/linux/i386/crt0.S')
| -rw-r--r-- | libc/sysdeps/linux/i386/crt0.S | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/libc/sysdeps/linux/i386/crt0.S b/libc/sysdeps/linux/i386/crt0.S index a488d6508..e7df6992b 100644 --- a/libc/sysdeps/linux/i386/crt0.S +++ b/libc/sysdeps/linux/i386/crt0.S @@ -18,6 +18,7 @@ Cambridge, MA 02139, USA. */ /* Based on the code from GNU libc, but hacked up by John Beppu and Erik Andersen */ +/* adapted by PaX Team for ET_DYN/PIE binaries */ /* When we enter this piece of code, the program stack looks like this: @@ -37,7 +38,7 @@ Cambridge, MA 02139, USA. */ .global _start .type _start,%function -#if defined L_crt0 || ! defined __UCLIBC_CTOR_DTOR__ +#if defined L_crt0 || defined L_Scrt0 || ! defined __UCLIBC_CTOR_DTOR__ .type __uClibc_main,%function #else .weak _init @@ -74,10 +75,22 @@ _start: pushl %ebp /* callers %ebp (frame pointer) */ movl %esp,%ebp /* mark callers stack frame as invalid */ -#if (defined L_crt1 || defined L_gcrt1 ) && defined __UCLIBC_CTOR_DTOR__ +#if defined L_Scrt0 || defined L_Scrt1 + call .L0 +.L0: + pop %edx + addl $_GLOBAL_OFFSET_TABLE_+[.-.L0],%edx +#endif + +#if (defined L_crt1 || defined L_Scrt1 || defined L_gcrt1 ) && defined __UCLIBC_CTOR_DTOR__ /* Push .init and .fini arguments to __uClibc_start_main() on the stack */ +#ifdef L_Scrt1 + pushl _fini@GOT(%edx) + pushl _init@GOT(%edx) +#else pushl $_fini pushl $_init +#endif /* Push envp, argc, and argc arguments to __uClibc_start_main() on the stack */ pushl %eax /* Environment pointer */ @@ -85,15 +98,23 @@ _start: pushl %ecx /* And the argument count */ /* Ok, now run uClibc's main() -- shouldn't return */ +#ifdef L_Scrt1 + call *__uClibc_start_main@GOT(%edx) +#else call __uClibc_start_main +#endif #else /* Push envp, argc, and argc arguments to __uClibc_start_main() on the stack */ pushl %eax /* Environment pointer */ pushl %ebx /* Argument pointer */ pushl %ecx /* And the argument count */ +#ifdef L_Scrt0 + call *__uClibc_main@GOT(%edx) +#else call __uClibc_main #endif +#endif /* Crash if somehow `exit' returns anyways. */ hlt |