libburnia/libisofs
2
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

When deciding boot flag, consider MBR partition slot empty only if entirely 0

Browse Source
This commit is contained in:
Thomas Schmitt 2017-02-27 18:27:59 +01:00
parent e66b9bfe0c
commit 5600f3d726
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
libisofs/system_area.c
View File

@ -192,6 +192,19 @@ int iso_compute_append_partitions(Ecma119Image *t, int flag)
}
static int mbr_part_slot_is_unused(uint8_t *slot)
{
int i;
for (i = 0; i < 16; i++)
if (slot[i] != 0)
break;
if (i >= 16)
return 1;
return 0;
}
/* @param flag
bit1= partition_offset and partition_size are counted in
blocks of 512 rather than 2048
@ -1777,7 +1790,7 @@ static void iso_dummy_mbr_partition(uint8_t *buf, int mode)
0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00 };
for (i = 0; i < 4; i++) {
if (buf[446 + 16 * i + 4] == 0x00) {
if (mbr_part_slot_is_unused(buf + 446 + 16 * i)) {
memcpy(buf + 446 + 16 * i, dummy_entry, 16);
return;
}
@ -2125,7 +2138,7 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
break;
if (i >= 4) { /* no bootable/active flag set yet */
for (i = 0; i < 4; i++) {
if (buf[446 + 16 * i + 4] != 0x00 &&
if ((!mbr_part_slot_is_unused(buf + 446 + 16 * i)) &&
buf[446 + 16 * i + 4] != 0xee &&
buf[446 + 16 * i + 4] != 0xef) {
buf[446 + 16 * i] |= 0x80;