static int munmap_seized(struct parasite_ctl *ctl, void *addr, size_t length)
{
unsigned long x;
return syscall_seized(ctl, __NR_munmap, &x,
(unsigned long)addr, length, 0, 0, 0, 0);
}
void *mmap_seized(struct parasite_ctl *ctl,
void *addr, size_t length, int prot,
int flags, int fd, off_t offset)
{
unsigned long map;
int err;
err = syscall_seized(ctl, __NR_mmap, &map,
(unsigned long)addr, length, prot, flags, fd, offset);
if (err < 0 || map > TASK_SIZE)
map = 0;
return (void *)map;
}
void *mmap_seized(struct parasite_ctl *ctl,
void *addr, size_t length, int prot,
int flags, int fd, off_t offset)
{
unsigned long map;
int err;
err = syscall_seized(ctl, __NR_mmap, &map,
(unsigned long)addr, length, prot, flags, fd, offset);
if (err < 0)
return NULL;
if (IS_ERR_VALUE(map)) {
if (map == -EACCES && (prot & PROT_WRITE) && (prot & PROT_EXEC))
pr_warn("mmap(PROT_WRITE | PROT_EXEC) failed for %d, "
"check selinux execmem policy\n", ctl->pid.real);
return NULL;
}
return (void *)map;
}
static int execute_syscall(struct parasite_ctl *ctl,
struct syscall_exec_desc *scd, char **opt)
{
int i, err;
unsigned long args[MAX_ARGS] = {}, ret, r_mem_size = 0;
unsigned int ret_args[MAX_ARGS] = {};
void *r_mem = NULL;
for (i = 0; i < MAX_ARGS; i++) {
if (opt[i] == NULL)
break;
/*
* &foo -- argument string "foo"
* @<size> -- ret-arg of size <size>
*/
if ((opt[i][0] == '&') || (opt[i][0] == '@')) {
int len;
if (!r_mem) {
err = parasite_map_exchange(ctl, PAGE_SIZE);
if (err)
return err;
r_mem_size = PAGE_SIZE;
r_mem = ctl->local_map;
}
if (opt[i][0] == '&') {
len = strlen(opt[i]);
if (r_mem_size < len) {
pr_err("Arg size overflow\n");
return -1;
}
memcpy(r_mem, opt[i] + 1, len);
} else {
len = strtol(opt[i] + 1, NULL, 0);
if (!len || (r_mem_size < len)) {
pr_err("Bad argument size %d\n", len);
return -1;
}
ret_args[i] = len;
}
args[i] = (unsigned long)ctl->remote_map + (r_mem - ctl->local_map);
pr_info("Pushing %c mem arg [%s]\n", opt[i][0], (char *)r_mem);
r_mem_size -= len;
r_mem += len;
} else
args[i] = strtol(opt[i], NULL, 0);
}
pr_info("Calling %d with %lu %lu %lu %lu %lu %lu\n", scd->nr,
args[0], args[1], args[2], args[3], args[4], args[5]);
err = syscall_seized(ctl, scd->nr, &ret,
args[0], args[1], args[2], args[3], args[4], args[5]);
if (err)
return err;
pr_msg("Syscall returned %lx(%d)\n", ret, (int)ret);
for (i = 0; i < MAX_ARGS; i++) {
unsigned long addr;
if (!ret_args[i])
continue;
pr_msg("Argument %d returns:\n", i);
addr = (unsigned long)ctl->local_map + (args[i] - (unsigned long)ctl->remote_map);
print_data(0, (unsigned char *)addr, ret_args[i]);
}
return 0;
}
