[PATCH 1/3] biosdisk: Fix handling of unknown partition types

[Vladimir Serbinenko]

On unknown partition types we end up dereferencing
a random pointer. Instead ensure that pointer is NULL
and skip it when it's NULL
---
 sys/arch/i386/stand/efiboot/efidisk.c | 2 +-
 sys/arch/i386/stand/lib/biosdisk.c    | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/arch/i386/stand/efiboot/efidisk.c 
b/sys/arch/i386/stand/efiboot/efidisk.c
index 57c399aad71..5381ab736ac 100644
--- a/sys/arch/i386/stand/efiboot/efidisk.c
+++ b/sys/arch/i386/stand/efiboot/efidisk.c
@@ -393,7 +393,7 @@ efidisk_get_efi_system_partition(int dev, int *partition)
                        continue;
                if (part[i].fstype == FS_UNUSED)
                        continue;
-               if (guid_is_equal(part[i].guid->guid, &GET_efi))
+               if (part[i].guid && guid_is_equal(part[i].guid->guid, &GET_efi))
                        break;
        }
        dealloc_biosdisk_part(part, nparts);
diff --git a/sys/arch/i386/stand/lib/biosdisk.c 
b/sys/arch/i386/stand/lib/biosdisk.c
index 02a9dcf0fa1..d8914c1647b 100644
--- a/sys/arch/i386/stand/lib/biosdisk.c
+++ b/sys/arch/i386/stand/lib/biosdisk.c
@@ -400,6 +400,7 @@ check_gpt(struct biosdisk *d, daddr_t rf_offset, daddr_t 
sector)
        entblk = gpth.hdr_lba_table + rf_offset;
        crc = crc32(0, NULL, 0);
 
+       memset(d->part, 0, sizeof(d->part));
        j = 0;
        ep = (const struct gpt_ent *)d->buf;
 
-- 
2.48.1