region: Introduce region_create() functions

We introduce two new functions to create region objects. They allow us
to check for integer overflows (region_create_untrusted()) or assert
their absence (region_create()).

This fixes potential overflows in region_overlap() checks in SMI
handlers, where we would wrongfully report MMIO as *not* overlapping
SMRAM.

Also, two cases of strtol() in parse_region() (cbfstool),  where the
results were implicitly converted to `size_t`, are replaced with the
unsigned strtoul().

FIT payload support is left out, as it doesn't use the region API
(only the struct).

Change-Id: I4ae3e6274c981c9ab4fb1263c2a72fa68ef1c32b
Ticket: https://ticket.coreboot.org/issues/522
Found-by: Vadim Zaliva <lord@digamma.ai>
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79905
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
This commit is contained in:
Nico Huber
2024-01-11 18:59:24 +01:00
committed by Felix Held
parent 0e9830884c
commit af0d4bce65
12 changed files with 95 additions and 75 deletions

View File

@ -820,15 +820,22 @@ static int cmd_add(void)
return 0;
}
static void parse_region(struct region *r, char *arg)
static int parse_region(struct region *r, char *arg)
{
char *tok;
tok = strtok(arg, ":");
r->offset = strtol(tok, NULL, 0);
unsigned long offset = strtoul(tok, NULL, 0);
tok = strtok(NULL, ":");
r->size = strtol(tok, NULL, 0);
unsigned long size = strtoul(tok, NULL, 0);
if (region_create_untrusted(r, offset, size) != CB_SUCCESS) {
ERROR("Invalid region: %lx:%lx\n", offset, size);
return -1;
}
return 0;
}
static struct command {
@ -991,19 +998,24 @@ int main(int argc, char **argv)
params.partition_type = atoi(optarg);
break;
case LONGOPT_BP1:
parse_region(&params.layout_regions[BP1], optarg);
if (parse_region(&params.layout_regions[BP1], optarg))
return 1;
break;
case LONGOPT_BP2:
parse_region(&params.layout_regions[BP2], optarg);
if (parse_region(&params.layout_regions[BP2], optarg))
return 1;
break;
case LONGOPT_BP3:
parse_region(&params.layout_regions[BP3], optarg);
if (parse_region(&params.layout_regions[BP3], optarg))
return 1;
break;
case LONGOPT_BP4:
parse_region(&params.layout_regions[BP4], optarg);
if (parse_region(&params.layout_regions[BP4], optarg))
return 1;
break;
case LONGOPT_DATA:
parse_region(&params.layout_regions[DP], optarg);
if (parse_region(&params.layout_regions[DP], optarg))
return 1;
break;
case LONGOPT_BP1_FILE:
params.layout_files[BP1] = optarg;