diff options
| author | ae <ae@FreeBSD.org> | 2011-06-27 10:42:06 +0000 |
|---|---|---|
| committer | ae <ae@FreeBSD.org> | 2011-06-27 10:42:06 +0000 |
| commit | c7b111bbcf014d13ab4bcabf0d7e68e5f9a5e5b7 (patch) | |
| tree | b49b13b4cca427e8f68ef329fbd7a69156ad7c2f /sys/geom | |
| parent | bfdf57abb6fca38cfaa291a8949cf125eb2912f2 (diff) | |
| download | FreeBSD-src-c7b111bbcf014d13ab4bcabf0d7e68e5f9a5e5b7.zip FreeBSD-src-c7b111bbcf014d13ab4bcabf0d7e68e5f9a5e5b7.tar.gz | |
MS Windows NT+ uses 4 bytes at offset 0x1b8 in the MBR to identify
disk drive. The boot0cfg(8) utility preserves these 4 bytes when is
writing bootcode to keep a multiboot ability.
Change gpart's bootcode method to keep DSN if it is not zero. Also
do not allow writing bootcode with size not equal to MBRSIZE.
PR: kern/157819
Tested by: Eir Nym
MFC after: 1 month
Diffstat (limited to 'sys/geom')
| -rw-r--r-- | sys/geom/part/g_part_mbr.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/sys/geom/part/g_part_mbr.c b/sys/geom/part/g_part_mbr.c index 825a109..bebdfee 100644 --- a/sys/geom/part/g_part_mbr.c +++ b/sys/geom/part/g_part_mbr.c @@ -237,14 +237,16 @@ static int g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp) { struct g_part_mbr_table *table; - size_t codesz; + uint32_t dsn; + + if (gpp->gpp_codesize != MBRSIZE) + return (ENODEV); - codesz = DOSPARTOFF; table = (struct g_part_mbr_table *)basetable; - bzero(table->mbr, codesz); - codesz = MIN(codesz, gpp->gpp_codesize); - if (codesz > 0) - bcopy(gpp->gpp_codeptr, table->mbr, codesz); + dsn = *(uint32_t *)(table->mbr + DOSDSNOFF); + bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF); + if (dsn != 0) + *(uint32_t *)(table->mbr + DOSDSNOFF) = dsn; return (0); } |
