Use version "2" in the superblock when data and metadata devices are separate, so that the device is no accidentally read by older kernel version.
Signed-off-by: Mikulas Patocka <[email protected]> --- drivers/md/dm-integrity.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) Index: linux-2.6/drivers/md/dm-integrity.c =================================================================== --- linux-2.6.orig/drivers/md/dm-integrity.c 2018-06-06 17:08:23.000000000 +0200 +++ linux-2.6/drivers/md/dm-integrity.c 2018-06-06 17:08:23.000000000 +0200 @@ -44,7 +44,8 @@ */ #define SB_MAGIC "integrt" -#define SB_VERSION 1 +#define SB_VERSION_1 1 +#define SB_VERSION_2 2 #define SB_SECTORS 8 #define MAX_SECTORS_PER_BLOCK 8 @@ -414,6 +415,14 @@ static void wraparound_section(struct dm *sec_ptr -= ic->journal_sections; } +static void sb_set_version(struct dm_integrity_c *ic) +{ + if (ic->meta_dev) + ic->sb->version = SB_VERSION_2; + else + ic->sb->version = SB_VERSION_1; +} + static int sync_rw_sb(struct dm_integrity_c *ic, int op, int op_flags) { struct dm_io_request io_req; @@ -2431,7 +2440,6 @@ static int initialize_superblock(struct memset(ic->sb, 0, SB_SECTORS << SECTOR_SHIFT); memcpy(ic->sb->magic, SB_MAGIC, 8); - ic->sb->version = SB_VERSION; ic->sb->integrity_tag_size = cpu_to_le16(ic->tag_size); ic->sb->log2_sectors_per_block = __ffs(ic->sectors_per_block); if (ic->journal_mac_alg.alg_string) @@ -2488,6 +2496,8 @@ try_smaller_buffer: ic->sb->provided_data_sectors = cpu_to_le64(ic->provided_data_sectors); + sb_set_version(ic); + return 0; } @@ -3185,7 +3195,7 @@ static int dm_integrity_ctr(struct dm_ta should_write_sb = true; } - if (ic->sb->version != SB_VERSION) { + if (!ic->sb->version || ic->sb->version > SB_VERSION_2) { r = -EINVAL; ti->error = "Unknown version"; goto bad; -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
