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author | Michael Weiß <michael.weiss@aisec.fraunhofer.de> | 2021-09-04 12:59:29 +0300 |
---|---|---|
committer | Mike Snitzer <snitzer@redhat.com> | 2021-10-27 23:54:36 +0300 |
commit | 82bb85998cc9a3d26f6086c80fae7888db3b3fd9 (patch) | |
tree | 1d2100b49665d49a415ddd0c63f1d831f369ccbc /drivers/md | |
parent | 2cc1ae4878282c75a569e8ec677d569601c99dda (diff) | |
download | linux-82bb85998cc9a3d26f6086c80fae7888db3b3fd9.tar.xz |
dm integrity: log audit events for dm-integrity target
dm-integrity signals integrity violations by returning I/O errors
to user space. To identify integrity violations by a controlling
instance, the kernel audit subsystem can be used to emit audit
events to user space. We use the new dm-audit submodule allowing
to emit audit events on relevant I/O errors.
The construction and destruction of integrity device mappings are
also relevant for auditing a system. Thus, those events are also
logged as audit events.
Signed-off-by: Michael Weiß <michael.weiss@aisec.fraunhofer.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/Kconfig | 1 | ||||
-rw-r--r-- | drivers/md/dm-integrity.c | 25 |
2 files changed, 22 insertions, 4 deletions
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 1bc4f48e9765..b5ea378e66cb 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -610,6 +610,7 @@ config DM_INTEGRITY select CRYPTO select CRYPTO_SKCIPHER select ASYNC_XOR + select DM_AUDIT if AUDIT help This device-mapper target emulates a block device that has additional per-sector tags that can be used for storing diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index dc03b70f6e65..dd78baf4c7af 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -23,6 +23,8 @@ #include <linux/async_tx.h> #include <linux/dm-bufio.h> +#include "dm-audit.h" + #define DM_MSG_PREFIX "integrity" #define DEFAULT_INTERLEAVE_SECTORS 32768 @@ -539,6 +541,7 @@ static int sb_mac(struct dm_integrity_c *ic, bool wr) } if (memcmp((__u8 *)ic->sb + (1 << SECTOR_SHIFT) - size, result, size)) { dm_integrity_io_error(ic, "superblock mac", -EILSEQ); + dm_audit_log_target(DM_MSG_PREFIX, "mac-superblock", ic->ti, 0); return -EILSEQ; } } @@ -876,8 +879,10 @@ static void rw_section_mac(struct dm_integrity_c *ic, unsigned section, bool wr) if (likely(wr)) memcpy(&js->mac, result + (j * JOURNAL_MAC_PER_SECTOR), JOURNAL_MAC_PER_SECTOR); else { - if (memcmp(&js->mac, result + (j * JOURNAL_MAC_PER_SECTOR), JOURNAL_MAC_PER_SECTOR)) + if (memcmp(&js->mac, result + (j * JOURNAL_MAC_PER_SECTOR), JOURNAL_MAC_PER_SECTOR)) { dm_integrity_io_error(ic, "journal mac", -EILSEQ); + dm_audit_log_target(DM_MSG_PREFIX, "mac-journal", ic->ti, 0); + } } } } @@ -1782,10 +1787,15 @@ again: if (unlikely(r)) { if (r > 0) { char b[BDEVNAME_SIZE]; - DMERR_LIMIT("%s: Checksum failed at sector 0x%llx", bio_devname(bio, b), - (sector - ((r + ic->tag_size - 1) / ic->tag_size))); + sector_t s; + + s = sector - ((r + ic->tag_size - 1) / ic->tag_size); + DMERR_LIMIT("%s: Checksum failed at sector 0x%llx", + bio_devname(bio, b), s); r = -EILSEQ; atomic64_inc(&ic->number_of_mismatches); + dm_audit_log_bio(DM_MSG_PREFIX, "integrity-checksum", + bio, s, 0); } if (likely(checksums != checksums_onstack)) kfree(checksums); @@ -1991,6 +2001,8 @@ retry_kmap: if (unlikely(memcmp(checksums_onstack, journal_entry_tag(ic, je), ic->tag_size))) { DMERR_LIMIT("Checksum failed when reading from journal, at sector 0x%llx", logical_sector); + dm_audit_log_bio(DM_MSG_PREFIX, "journal-checksum", + bio, logical_sector, 0); } } #endif @@ -2534,8 +2546,10 @@ static void do_journal_write(struct dm_integrity_c *ic, unsigned write_start, integrity_sector_checksum(ic, sec + ((l - j) << ic->sb->log2_sectors_per_block), (char *)access_journal_data(ic, i, l), test_tag); - if (unlikely(memcmp(test_tag, journal_entry_tag(ic, je2), ic->tag_size))) + if (unlikely(memcmp(test_tag, journal_entry_tag(ic, je2), ic->tag_size))) { dm_integrity_io_error(ic, "tag mismatch when replaying journal", -EILSEQ); + dm_audit_log_target(DM_MSG_PREFIX, "integrity-replay-journal", ic->ti, 0); + } } journal_entry_set_unused(je2); @@ -4514,9 +4528,11 @@ try_smaller_buffer: if (ic->discard) ti->num_discard_bios = 1; + dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); return 0; bad: + dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); dm_integrity_dtr(ti); return r; } @@ -4590,6 +4606,7 @@ static void dm_integrity_dtr(struct dm_target *ti) free_alg(&ic->journal_mac_alg); kfree(ic); + dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); } static struct target_type integrity_target = { |