[RESEND PATCH 08/11] dm-verity: add bdev_setsecurity hook for root-hash

deven.desai
2020-04-06T18:11:05Z

Add a security hook call to set a security property of a block_device
in dm-verity with the root-hash that was verified to match the merkel-tree.

Signed-off-by: Deven Bowers <deven.desai@linux.microsoft.com>
---
drivers/md/dm-verity-target.c | 8 ++++++++
include/linux/device-mapper.h | 1 +
2 files changed, 9 insertions(+)

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index c507f3a4e237..225f67ab378d 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -16,8 +16,10 @@
#include "dm-verity.h"
#include "dm-verity-fec.h"
#include "dm-verity-verify-sig.h"
+#include "dm-core.h"
#include <linux/module.h>
#include <linux/reboot.h>
+#include <linux/security.h>

#define DM_MSG_PREFIX "verity"

@@ -530,6 +532,12 @@ static int verity_verify_io(struct dm_verity_io *io)
return -EIO;
}

+ r = security_bdev_setsecurity(dm_table_get_md(v->ti->table)->bdev,
+ DM_VERITY_ROOTHASH_SEC_NAME,
+ v->root_digest, v->digest_size);
+ if (unlikely(r < 0))
+ return r;
+
/*
* At this point, the merkel tree has finished validating.
* if signature was specified, validate the signature here.
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 6bd49aa48186..467db44de194 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -625,5 +625,6 @@ static inline unsigned long to_bytes(sector_t n)
}

#define DM_VERITY_SIGNATURE_SEC_NAME DM_NAME ".verity-sig"
+#define DM_VERITY_ROOTHASH_SEC_NAME DM_NAME ".verity-rh"

#endif /* _LINUX_DEVICE_MAPPER_H */
--
2.26.0