diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/vendorcode/google/chromeos/fmap.c | 13 | ||||
| -rw-r--r-- | src/vendorcode/google/chromeos/fmap.h | 2 |
2 files changed, 10 insertions, 5 deletions
diff --git a/src/vendorcode/google/chromeos/fmap.c b/src/vendorcode/google/chromeos/fmap.c index 50b0248783..21d439e07d 100644 --- a/src/vendorcode/google/chromeos/fmap.c +++ b/src/vendorcode/google/chromeos/fmap.c @@ -26,10 +26,15 @@ static int is_fmap_signature_valid(const struct fmap *fmap) { - if (memcmp(fmap, FMAP_SIGNATURE, sizeof(FMAP_SIGNATURE) - 1)) { - printk(BIOS_ERR, "No FMAP found at %p.\n", fmap); - return 1; - } + const char reversed_sig[] = FMAP_REVERSED_SIGNATURE; + const char *p2 = reversed_sig + sizeof(FMAP_REVERSED_SIGNATURE) - 2; + const char *p1 = (char *)fmap; + + while (p2 >= reversed_sig) + if (*p1++ != *p2--) { + printk(BIOS_ERR, "No FMAP found at %p.\n", fmap); + return 1; + } printk(BIOS_DEBUG, "FMAP: Found \"%s\" version %d.%d at %p.\n", fmap->name, fmap->ver_major, fmap->ver_minor, fmap); diff --git a/src/vendorcode/google/chromeos/fmap.h b/src/vendorcode/google/chromeos/fmap.h index a3d2abd582..05d3fb6e1d 100644 --- a/src/vendorcode/google/chromeos/fmap.h +++ b/src/vendorcode/google/chromeos/fmap.h @@ -38,7 +38,7 @@ #include <stdint.h> -#define FMAP_SIGNATURE "__FMAP__" +#define FMAP_REVERSED_SIGNATURE "__PAMF__" /* avoid magic number in .rodata */ #define FMAP_VER_MAJOR 1 /* this header's FMAP minor version */ #define FMAP_VER_MINOR 1 /* this header's FMAP minor version */ #define FMAP_STRLEN 32 /* maximum length for strings, */ |