elf_fdpic_transfer_args_to_stack(): make it generic

This copying of arguments and environment is common to both NOMMU
binary formats we support. Let's make the elf_fdpic version available
to the flat format as well.

While at it, improve the code a bit not to copy below the actual
data area.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
This commit is contained in:
Nicolas Pitre
2016-07-24 11:30:18 -04:00
committed by Greg Ungerer
parent c995ee28d2
commit 7e7ec6a934
3 changed files with 37 additions and 36 deletions

View File

@@ -762,6 +762,39 @@ out_unlock:
}
EXPORT_SYMBOL(setup_arg_pages);
#else
/*
* Transfer the program arguments and environment from the holding pages
* onto the stack. The provided stack pointer is adjusted accordingly.
*/
int transfer_args_to_stack(struct linux_binprm *bprm,
unsigned long *sp_location)
{
unsigned long index, stop, sp;
int ret = 0;
stop = bprm->p >> PAGE_SHIFT;
sp = *sp_location;
for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0;
char *src = kmap(bprm->page[index]) + offset;
sp -= PAGE_SIZE - offset;
if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0)
ret = -EFAULT;
kunmap(bprm->page[index]);
if (ret)
goto out;
}
*sp_location = sp;
out:
return ret;
}
EXPORT_SYMBOL(transfer_args_to_stack);
#endif /* CONFIG_MMU */
static struct file *do_open_execat(int fd, struct filename *name, int flags)