You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

114 lines
3.9 KiB

diff -up util-linux-2.23.2/libblkid/src/partitions/dos.c.kzak util-linux-2.23.2/libblkid/src/partitions/dos.c
--- util-linux-2.23.2/libblkid/src/partitions/dos.c.kzak 2015-08-21 10:16:45.244332027 +0200
+++ util-linux-2.23.2/libblkid/src/partitions/dos.c 2015-08-21 10:22:07.181340367 +0200
@@ -151,16 +151,6 @@ static int probe_dos_pt(blkid_probe pr,
if (memcmp(data, BLKID_AIX_MAGIC_STRING, BLKID_AIX_MAGIC_STRLEN) == 0)
goto nothing;
- /*
- * Now that the 55aa signature is present, this is probably
- * either the boot sector of a FAT filesystem or a DOS-type
- * partition table.
- */
- if (blkid_probe_is_vfat(pr) == 1) {
- DBG(LOWPROBE, blkid_debug("probably FAT -- ignore"));
- goto nothing;
- }
-
p0 = (struct dos_partition *) (data + BLKID_MSDOS_PT_OFFSET);
/*
@@ -182,6 +172,16 @@ static int probe_dos_pt(blkid_probe pr,
}
}
+ /*
+ * Now that the 55aa signature is present, this is probably
+ * either the boot sector of a FAT filesystem or a DOS-type
+ * partition table.
+ */
+ if (blkid_probe_is_vfat(pr) == 1) {
+ DBG(LOWPROBE, blkid_debug("probably FAT -- ignore"));
+ goto nothing;
+ }
+
blkid_probe_use_wiper(pr, BLKID_MSDOS_PT_OFFSET,
512 - BLKID_MSDOS_PT_OFFSET);
diff -up util-linux-2.23.2/libblkid/src/partitions/dos.h.kzak util-linux-2.23.2/libblkid/src/partitions/dos.h
--- util-linux-2.23.2/libblkid/src/partitions/dos.h.kzak 2015-08-21 10:34:14.919380422 +0200
+++ util-linux-2.23.2/libblkid/src/partitions/dos.h 2015-08-21 10:35:45.221807669 +0200
@@ -12,6 +12,12 @@ struct dos_partition {
#define BLKID_MSDOS_PT_OFFSET 0x1be
+static inline struct dos_partition *mbr_get_partition(unsigned char *mbr, int i)
+{
+ return (struct dos_partition *)
+ (mbr + BLKID_MSDOS_PT_OFFSET + (i * sizeof(struct dos_partition)));
+}
+
/* assemble badly aligned little endian integer */
static inline unsigned int assemble4le(const unsigned char *p)
{
diff -up util-linux-2.23.2/libblkid/src/superblocks/vfat.c.kzak util-linux-2.23.2/libblkid/src/superblocks/vfat.c
--- util-linux-2.23.2/libblkid/src/superblocks/vfat.c.kzak 2015-08-21 10:10:12.111906711 +0200
+++ util-linux-2.23.2/libblkid/src/superblocks/vfat.c 2015-08-21 10:35:07.733045452 +0200
@@ -16,6 +16,7 @@
#include <ctype.h>
#include <stdint.h>
+#include "partitions/dos.h"
#include "superblocks.h"
/* Yucky misaligned values */
@@ -169,7 +170,8 @@ static unsigned char *search_fat_label(b
return NULL;
}
-static int fat_valid_superblock(const struct blkid_idmag *mag,
+static int fat_valid_superblock(blkid_probe pr,
+ const struct blkid_idmag *mag,
struct msdos_super_block *ms,
struct vfat_super_block *vs,
uint32_t *cluster_count, uint32_t *fat_size)
@@ -243,6 +245,20 @@ static int fat_valid_superblock(const st
if (cluster_count)
*cluster_count = __cluster_count;
+ if (blkid_probe_is_wholedisk(pr)) {
+ /* OK, seems like FAT, but it's possible that we found boot
+ * sector with crazy FAT-like stuff (magic strings, media,
+ * etc..) before MBR. Let's make sure that there is no MBR with
+ * usable partition. */
+ unsigned char *buf = (unsigned char *) ms;
+ if (is_valid_mbr_signature(buf)) {
+ struct dos_partition *p0 = mbr_get_partition(buf, 0);
+ if (dos_partition_size(p0) != 0 &&
+ (p0->boot_ind == 0 || p0->boot_ind == 0x80))
+ return 0;
+ }
+ }
+
return 1; /* valid */
}
@@ -270,7 +286,7 @@ int blkid_probe_is_vfat(blkid_probe pr)
if (!vs)
return errno ? -errno : 0;
- return fat_valid_superblock(mag, ms, vs, NULL, NULL);
+ return fat_valid_superblock(pr, mag, ms, vs, NULL, NULL);
}
/* FAT label extraction from the root directory taken from Kay
@@ -293,7 +309,7 @@ static int probe_vfat(blkid_probe pr, co
if (!vs)
return errno ? -errno : 1;
- if (!fat_valid_superblock(mag, ms, vs, &cluster_count, &fat_size))
+ if (!fat_valid_superblock(pr, mag, ms, vs, &cluster_count, &fat_size))
return 1;
sector_size = unaligned_le16(&ms->ms_sector_size);