On Tue, Apr 18, 2017 at 3:52 PM, Baoquan He <b...@redhat.com> wrote: > On 04/18/17 at 01:22pm, Kees Cook wrote: >> > +#define COMMAND_LINE_SIZE 256 >> > +static int handle_mem_memmap(void) >> > +{ >> > + char *args = (char *)get_cmd_line_ptr(); >> > + char tmp_cmdline[COMMAND_LINE_SIZE]; >> >> Can't this use a dynamic allocation instead of the 256 limit? > > This is in boot/compressed code, no mm allocator built yet? Am I right?
misc.c uses malloc for phdrs, and the boot_heap is create to build an area for those calls, see include/linux/decompress/mm.h. I *think* it should be safe to use malloc here. It should be a pretty small allocation normally. -Kees -- Kees Cook Pixel Security