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/* Code for loading Linux executables. Mostly linux kernel code. */
#include "qemu/osdep.h"
#include "qemu.h"
#include "user-internals.h"
#include "loader.h"
#define NGROUPS 32
/* ??? This should really be somewhere else. */
abi_long memcpy_to_target(abi_ulong dest, const void *src, unsigned long len)
{
void *host_ptr;
host_ptr = lock_user(VERIFY_WRITE, dest, len, 0);
if (!host_ptr) {
return -TARGET_EFAULT;
}
memcpy(host_ptr, src, len);
unlock_user(host_ptr, dest, 1);
return 0;
}
static int count(char **vec)
{
int i;
for (i = 0; *vec; i++) {
vec++;
}
return i;
}
static int prepare_binprm(struct linux_binprm *bprm)
{
struct stat st;
int mode;
int retval;
if (fstat(bprm->fd, &st) < 0) {
return -errno;
}
mode = st.st_mode;
if (!S_ISREG(mode)) { /* Must be regular file */
return -EACCES;
}
if (!(mode & 0111)) { /* Must have at least one execute bit set */
return -EACCES;
}
bprm->e_uid = geteuid();
bprm->e_gid = getegid();
/* Set-uid? */
if (mode & S_ISUID) {
bprm->e_uid = st.st_uid;
}
/* Set-gid? */
/*
* If setgid is set but no group execute bit then this
* is a candidate for mandatory locking, not a setgid
* executable.
*/
if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
bprm->e_gid = st.st_gid;
}
retval = read(bprm->fd, bprm->buf, BPRM_BUF_SIZE);
if (retval < 0) {
perror("prepare_binprm");
exit(-1);
}
if (retval < BPRM_BUF_SIZE) {
/* Make sure the rest of the loader won't read garbage. */
memset(bprm->buf + retval, 0, BPRM_BUF_SIZE - retval);
}
return retval;
}
/* Construct the envp and argv tables on the target stack. */
abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
abi_ulong stringp, int push_ptr)
{
TaskState *ts = (TaskState *)thread_cpu->opaque;
int n = sizeof(abi_ulong);
abi_ulong envp;
abi_ulong argv;
sp -= (envc + 1) * n;
envp = sp;
sp -= (argc + 1) * n;
argv = sp;
if (push_ptr) {
/* FIXME - handle put_user() failures */
sp -= n;
put_user_ual(envp, sp);
sp -= n;
put_user_ual(argv, sp);
}
sp -= n;
/* FIXME - handle put_user() failures */
put_user_ual(argc, sp);
ts->info->arg_start = stringp;
while (argc-- > 0) {
/* FIXME - handle put_user() failures */
put_user_ual(stringp, argv);
argv += n;
stringp += target_strlen(stringp) + 1;
}
ts->info->arg_end = stringp;
/* FIXME - handle put_user() failures */
put_user_ual(0, argv);
while (envc-- > 0) {
/* FIXME - handle put_user() failures */
put_user_ual(stringp, envp);
envp += n;
stringp += target_strlen(stringp) + 1;
}
/* FIXME - handle put_user() failures */
put_user_ual(0, envp);
return sp;
}
int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
struct target_pt_regs *regs, struct image_info *infop,
struct linux_binprm *bprm)
{
int retval;
bprm->fd = fdexec;
bprm->filename = (char *)filename;
bprm->argc = count(argv);
bprm->argv = argv;
bprm->envc = count(envp);
bprm->envp = envp;
retval = prepare_binprm(bprm);
if (retval >= 0) {
if (bprm->buf[0] == 0x7f
&& bprm->buf[1] == 'E'
&& bprm->buf[2] == 'L'
&& bprm->buf[3] == 'F') {
retval = load_elf_binary(bprm, infop);
#if defined(TARGET_HAS_BFLT)
} else if (bprm->buf[0] == 'b'
&& bprm->buf[1] == 'F'
&& bprm->buf[2] == 'L'
&& bprm->buf[3] == 'T') {
retval = load_flt_binary(bprm, infop);
#endif
} else {
return -ENOEXEC;
}
}
if (retval >= 0) {
/* success. Initialize important registers */
do_init_thread(regs, infop);
return retval;
}
return retval;
}
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