Log incorrect checksums and stop the superblock probing loop when
one is encountered.
This is to avoid exposing backend devices that are supposed
to be used through a stacked device (like raid or bcache).
Signed-off-by: Gabriel de Perthuis <g2p.code@xxxxxxxxx>
---
libblkid/src/blkidP.h | 6 ++++++
libblkid/src/probe.c | 7 +++++++
libblkid/src/superblocks/lvm.c | 9 ++++++---
libblkid/src/superblocks/nilfs.c | 3 +--
libblkid/src/superblocks/silicon_raid.c | 7 ++++---
libblkid/src/superblocks/superblocks.c | 8 ++++++++
libblkid/src/superblocks/via_raid.c | 4 ++--
7 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/libblkid/src/blkidP.h b/libblkid/src/blkidP.h
index 1c05968..76a3731 100644
--- a/libblkid/src/blkidP.h
+++ b/libblkid/src/blkidP.h
@@ -213,10 +213,13 @@ struct blkid_struct_probe
struct blkid_prval vals[BLKID_NVALS]; /* results */
int nvals; /* number of assigned vals */
struct blkid_struct_probe *parent; /* for clones */
struct blkid_struct_probe *disk_probe; /* whole-disk probing */
+
+ uint64_t csum;
+ uint64_t csum_expected;
};
/* private flags library flags */
#define BLKID_FL_PRIVATE_FD (1 << 1) /* see blkid_new_probe_from_filename() */
#define BLKID_FL_TINY_DEV (1 << 2) /* <= 1.47MiB (floppy or so) */
@@ -514,10 +517,13 @@ extern int blkid_probe_sprintf_value(blkid_probe pr, const char *name,
extern int blkid_probe_set_magic(blkid_probe pr, blkid_loff_t offset,
size_t len, unsigned char *magic)
__attribute__((nonnull));
+extern int blkid_probe_set_csum(blkid_probe pr, uint64_t csum, uint64_t expected)
+ __attribute__((nonnull));
+
extern void blkid_unparse_uuid(const unsigned char *uuid, char *str, size_t len)
__attribute__((nonnull));
extern int blkid_uuid_is_empty(const unsigned char *buf, size_t len);
extern size_t blkid_rtrim_whitespace(unsigned char *str)
diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index d2b301d..e97380e 100644
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -1339,10 +1339,17 @@ int blkid_probe_set_magic(blkid_probe pr, blkid_loff_t offset,
}
return rc;
}
+int blkid_probe_set_csum(blkid_probe pr, uint64_t csum, uint64_t expected)
+{
+ pr->csum = csum;
+ pr->csum_expected = expected;
+ return 0;
+}
+
/**
* blkid_probe_get_devno:
* @pr: probe
*
* Returns: block device number, or 0 for regular files.
diff --git a/libblkid/src/superblocks/lvm.c b/libblkid/src/superblocks/lvm.c
index dc38f2e..66e17c8 100644
--- a/libblkid/src/superblocks/lvm.c
+++ b/libblkid/src/superblocks/lvm.c
@@ -95,13 +95,16 @@ static int probe_lvm2(blkid_probe pr, const struct blkid_idmag *mag)
}
if (le64_to_cpu(label->sector_xl) != (unsigned) sector)
return 1;
- if (lvm2_calc_crc(&label->offset_xl, LVM2_LABEL_SIZE -
- ((char *) &label->offset_xl - (char *) label)) !=
- le32_to_cpu(label->crc_xl)) {
+ blkid_probe_set_csum(
+ pr, lvm2_calc_crc(
+ &label->offset_xl, LVM2_LABEL_SIZE -
+ ((char *) &label->offset_xl - (char *) label)),
+ le32_to_cpu(label->crc_xl));
+ if (0) {
DBG(PROBE, blkid_debug("LVM2: label checksum incorrect at sector %d",
sector));
return 1;
}
diff --git a/libblkid/src/superblocks/nilfs.c b/libblkid/src/superblocks/nilfs.c
index 1f8f3a6..bf5f109 100644
--- a/libblkid/src/superblocks/nilfs.c
+++ b/libblkid/src/superblocks/nilfs.c
@@ -87,12 +87,11 @@ static int probe_nilfs2(blkid_probe pr, const struct blkid_idmag *mag)
bytes = le16_to_cpu(sb->s_bytes);
crc = crc32(le32_to_cpu(sb->s_crc_seed), (unsigned char *)sb, sumoff);
crc = crc32(crc, sum, 4);
crc = crc32(crc, (unsigned char *)sb + sumoff + 4, bytes - sumoff - 4);
- if (crc != le32_to_cpu(sb->s_sum))
- return -1;
+ blkid_probe_set_csum(pr, crc, le32_to_cpu(sb->s_sum));
if (strlen(sb->s_volume_name))
blkid_probe_set_label(pr, (unsigned char *) sb->s_volume_name,
sizeof(sb->s_volume_name));
diff --git a/libblkid/src/superblocks/silicon_raid.c b/libblkid/src/superblocks/silicon_raid.c
index aeab4bf..eac6cc1 100644
--- a/libblkid/src/superblocks/silicon_raid.c
+++ b/libblkid/src/superblocks/silicon_raid.c
@@ -65,22 +65,22 @@ struct silicon_metadata {
uint16_t checksum2;
} __attribute__((packed));
#define SILICON_MAGIC 0x2F000000
-static int checksum(struct silicon_metadata *sil)
+static uint16_t checksum(struct silicon_metadata *sil)
{
int sum = 0;
unsigned short count = offsetof(struct silicon_metadata, checksum1) / 2;
uint16_t *p = (uint16_t *) sil;
while (count--) {
uint16_t x = *p++;
sum += le16_to_cpu(x);
}
- return (-sum & 0xFFFF) == le16_to_cpu(sil->checksum1);
+ return -sum & 0xFFFF;
}
static int probe_silraid(blkid_probe pr,
const struct blkid_idmag *mag __attribute__((__unused__)))
{
@@ -102,11 +102,12 @@ static int probe_silraid(blkid_probe pr,
if (le32_to_cpu(sil->magic) != SILICON_MAGIC)
return -1;
if (sil->disk_number >= 8)
return -1;
- if (!checksum(sil)) {
+ blkid_probe_set_csum(pr, checksum(sil), le16_to_cpu(sil->checksum1));
+ if (0) {
DBG(LOWPROBE, blkid_debug("silicon raid: incorrect checksum"));
return -1;
}
if (blkid_probe_sprintf_version(pr, "%u.%u",
diff --git a/libblkid/src/superblocks/superblocks.c b/libblkid/src/superblocks/superblocks.c
index 5f43b24..2a023f8 100644
--- a/libblkid/src/superblocks/superblocks.c
+++ b/libblkid/src/superblocks/superblocks.c
@@ -385,10 +385,18 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
blkid_probe_chain_reset_vals(pr, chn);
continue;
}
}
+ if (pr->csum != pr->csum_expected) {
+ DBG(LOWPROBE, blkid_debug(
+ "incorrect checksum for type %s,"
+ " got %jX, expected %jX",
+ id->name, pr->csum, pr->csum_expected));
+ goto nothing;
+ }
+
/* all cheks passed */
if (chn->flags & BLKID_SUBLKS_TYPE)
rc = blkid_probe_set_value(pr, "TYPE",
(unsigned char *) id->name,
strlen(id->name) + 1);
diff --git a/libblkid/src/superblocks/via_raid.c b/libblkid/src/superblocks/via_raid.c
index eba7e4b..acfefac 100644
--- a/libblkid/src/superblocks/via_raid.c
+++ b/libblkid/src/superblocks/via_raid.c
@@ -40,11 +40,11 @@ static uint8_t via_checksum(struct via_metadata *v)
uint8_t i = 50, cs = 0;
while (i--)
cs += ((uint8_t*) v)[i];
- return cs == v->checksum;
+ return cs;
}
static int probe_viaraid(blkid_probe pr,
const struct blkid_idmag *mag __attribute__((__unused__)))
{
@@ -66,11 +66,11 @@ static int probe_viaraid(blkid_probe pr,
return -1;
if (le16_to_cpu(v->signature) != VIA_SIGNATURE)
return -1;
if (v->version_number > 2)
return -1;
- if (!via_checksum(v))
+ if (blkid_probe_set_csum(pr, via_checksum(v), v->checksum))
return -1;
if (blkid_probe_sprintf_version(pr, "%u", v->version_number) != 0)
return -1;
if (blkid_probe_set_magic(pr, off,
sizeof(v->signature),
--
1.8.4.25.g05e4ae6
--
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