Minix/minix
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Removing CSU patches

Browse Source 
* Removed startup code patches in lib/csu regarding kernel to userland
   ABI.

 * Aligned stack layout on NetBSD stack layout.

 * Generate valid stack pointers instead of offsets by taking into account
   _minix_kerninfo->kinfo->user_sp.

 * Refactored stack generation, by moving part of execve in two
   functions {minix_stack_params(), minix_stack_fill()} and using them
   in execve(), rs and vm.

 * Changed load offset of rtld (ld.so) to:
      execi.args.stack_high - execi.args.stack_size - 0xa00000
   which is 10MB below the main executable stack.

Change-Id: I839daf3de43321cded44105634102d419cb36cec
This commit is contained in:
sambuc
2014-02-18 11:25:02 +01:00
parent 5d04b92e06
commit cfd3379bb1
29 changed files with 608 additions and 485 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/libc/sys-minix/execve.c
+18 -85
View File
@@ -1,6 +1,4 @@
/* execve() - basic program execution call Author: Kees J. Bot
* 21 Jan 1994
*/
/* execve() - basic program execution call */
#include <sys/cdefs.h>
#include "namespace.h"
@@ -9,7 +7,9 @@
#include <unistd.h>
#include <string.h>
#include <stddef.h>
#include <minix/param.h>
#include <sys/exec_elf.h>
#include <sys/exec.h>
#ifdef __weak_alias
__weak_alias(execve, _execve)
@@ -17,62 +17,21 @@ __weak_alias(execve, _execve)
int execve(const char *path, char * const *argv, char * const *envp)
{
char * const *ap;
char * const *ep;
char *frame;
char **vp;
char *sp;
size_t argc;
int extra;
int vectors;
size_t frame_size;
size_t string_off;
size_t n;
int ov;
message m;
size_t frame_size = 0; /* Size of the new initial stack. */
int argc = 0; /* Argument count. */
int envc = 0; /* Environment count */
char overflow = 0; /* No overflow yet. */
char *frame;
struct ps_strings *psp;
int vsp = 0; /* (virtual) Stack pointer in new address space. */
/* Assumptions: size_t and char *, it's all the same thing. */
/* Create a stack image that only needs to be patched up slightly
* by the kernel to be used for the process to be executed.
*/
ov= 0; /* No overflow yet. */
frame_size= 0; /* Size of the new initial stack. */
string_off= 0; /* Offset to start of the strings. */
argc= 0; /* Argument count. */
for (ap= argv; *ap != NULL; ap++) {
n = sizeof(*ap) + strlen(*ap) + 1;
frame_size+= n;
if (frame_size < n) ov= 1;
string_off+= sizeof(*ap);
argc++;
}
for (ep= envp; *ep != NULL; ep++) {
n = sizeof(*ep) + strlen(*ep) + 1;
frame_size+= n;
if (frame_size < n) ov= 1;
string_off+= sizeof(*ap);
}
/* Add an argument count, two terminating nulls and
* space for the ELF aux vectors, that must come before
* (i.e. at a higher address) then the strings.
*/
vectors = sizeof(argc) + sizeof(*ap) + sizeof(*ep) +
sizeof(AuxInfo) * PMEF_AUXVECTORS;
extra = vectors + PMEF_EXECNAMELEN1;
frame_size+= extra;
string_off+= extra;
/* Align. */
frame_size= (frame_size + sizeof(char *) - 1) & ~(sizeof(char *) - 1);
minix_stack_params(path, argv, envp, &frame_size, &overflow,
&argc, &envc);
/* The party is off if there is an overflow. */
if (ov || frame_size < 3 * sizeof(char *)) {
errno= E2BIG;
if (overflow) {
errno = E2BIG;
return -1;
}
@@ -82,31 +41,8 @@ int execve(const char *path, char * const *argv, char * const *envp)
return -1;
}
/* Set arg count, init pointers to vector and string tables. */
* (size_t *) frame = argc;
vp = (char **) (frame + sizeof(argc));
sp = frame + string_off;
/* Load the argument vector and strings. */
for (ap= argv; *ap != NULL; ap++) {
*vp++= (char *) (sp - frame);
n= strlen(*ap) + 1;
memcpy(sp, *ap, n);
sp+= n;
}
*vp++= NULL;
/* Load the environment vector and strings. */
for (ep= envp; *ep != NULL; ep++) {
*vp++= (char *) (sp - frame);
n= strlen(*ep) + 1;
memcpy(sp, *ep, n);
sp+= n;
}
*vp++= NULL;
/* Padding. */
while (sp < frame + frame_size) *sp++= 0;
minix_stack_fill(path, argc, argv, envc, envp, frame_size, frame,
&vsp, &psp);
/* Clear unused message fields */
memset(&m, 0, sizeof(m));
@@ -116,15 +52,12 @@ int execve(const char *path, char * const *argv, char * const *envp)
m.m1_i2 = frame_size;
m.m1_p1 = (char *) __UNCONST(path);
m.m1_p2 = frame;
/* Tell PM/VFS we have left space for the aux vectors
* and executable name
*/
m.PMEXEC_FLAGS = PMEF_AUXVECTORSPACE | PMEF_EXECNAMESPACE1;
m.m1_p4 = (char *)(vsp + ((char *)psp - frame));
(void) _syscall(PM_PROC_NR, EXEC, &m);
/* Failure, return the memory used for the frame and exit. */
(void) sbrk(-frame_size);
return -1;
}