diff options
| -rw-r--r-- | Documentation/admin-guide/device-mapper/dm-integrity.rst | 6 | ||||
| -rw-r--r-- | drivers/md/dm-integrity.c | 24 |
2 files changed, 29 insertions, 1 deletions
diff --git a/Documentation/admin-guide/device-mapper/dm-integrity.rst b/Documentation/admin-guide/device-mapper/dm-integrity.rst index a30aa91b5fbe..3463883844c0 100644 --- a/Documentation/admin-guide/device-mapper/dm-integrity.rst +++ b/Documentation/admin-guide/device-mapper/dm-integrity.rst @@ -177,6 +177,12 @@ bitmap_flush_interval:number The bitmap flush interval in milliseconds. The metadata buffers are synchronized when this interval expires. +legacy_recalculate + Allow recalculating of volumes with HMAC keys. This is disabled by + default for security reasons - an attacker could modify the volume, + set recalc_sector to zero, and the kernel would not detect the + modification. + The journal mode (D/J), buffer_sectors, journal_watermark, commit_time can be changed when reloading the target (load an inactive table and swap the diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 57f66f2ad98d..c967c2cdba87 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -254,6 +254,7 @@ struct dm_integrity_c { bool journal_uptodate; bool just_formatted; bool recalculate_flag; + bool legacy_recalculate; struct alg_spec internal_hash_alg; struct alg_spec journal_crypt_alg; @@ -381,6 +382,14 @@ static int dm_integrity_failed(struct dm_integrity_c *ic) return READ_ONCE(ic->failed); } +static bool dm_integrity_disable_recalculate(struct dm_integrity_c *ic) +{ + if ((ic->internal_hash_alg.key || ic->journal_mac_alg.key) && + !ic->legacy_recalculate) + return true; + return false; +} + static commit_id_t dm_integrity_commit_id(struct dm_integrity_c *ic, unsigned i, unsigned j, unsigned char seq) { @@ -2998,6 +3007,7 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type, arg_count += !!ic->internal_hash_alg.alg_string; arg_count += !!ic->journal_crypt_alg.alg_string; arg_count += !!ic->journal_mac_alg.alg_string; + arg_count += ic->legacy_recalculate; DMEMIT("%s %llu %u %c %u", ic->dev->name, (unsigned long long)ic->start, ic->tag_size, ic->mode, arg_count); if (ic->meta_dev) @@ -3017,6 +3027,8 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type, DMEMIT(" sectors_per_bit:%llu", (unsigned long long)ic->sectors_per_block << ic->log2_blocks_per_bitmap_bit); DMEMIT(" bitmap_flush_interval:%u", jiffies_to_msecs(ic->bitmap_flush_interval)); } + if (ic->legacy_recalculate) + DMEMIT(" legacy_recalculate"); #define EMIT_ALG(a, n) \ do { \ @@ -3625,7 +3637,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) unsigned extra_args; struct dm_arg_set as; static const struct dm_arg _args[] = { - {0, 15, "Invalid number of feature args"}, + {0, 14, "Invalid number of feature args"}, }; unsigned journal_sectors, interleave_sectors, buffer_sectors, journal_watermark, sync_msec; bool should_write_sb; @@ -3769,6 +3781,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) goto bad; } else if (!strcmp(opt_string, "recalculate")) { ic->recalculate_flag = true; + } else if (!strcmp(opt_string, "legacy_recalculate")) { + ic->legacy_recalculate = true; } else { r = -EINVAL; ti->error = "Invalid argument"; @@ -4067,6 +4081,14 @@ try_smaller_buffer: } } + if (ic->sb->flags & cpu_to_le32(SB_FLAG_RECALCULATING) && + le64_to_cpu(ic->sb->recalc_sector) < ic->provided_data_sectors && + dm_integrity_disable_recalculate(ic)) { + ti->error = "Recalculating with HMAC is disabled for security reasons - if you really need it, use the argument \"legacy_recalculate\""; + r = -EOPNOTSUPP; + goto bad; + } + ic->bufio = dm_bufio_client_create(ic->meta_dev ? ic->meta_dev->bdev : ic->dev->bdev, 1U << (SECTOR_SHIFT + ic->log2_buffer_sectors), 1, 0, NULL, NULL); if (IS_ERR(ic->bufio)) { |