Add mount option data to the blob size accounting in anticipation
of using a shared mnt_opts blob.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/lsm_hooks.h  | 1 +
 security/lsm_init.c        | 2 ++
 security/selinux/hooks.c   | 1 +
 security/smack/smack_lsm.c | 1 +
 4 files changed, 5 insertions(+)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 5bc144c5f685..9741c76e4654 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -122,6 +122,7 @@ struct lsm_blob_sizes {
 	unsigned int lbs_xattr_count; /* num xattr slots in new_xattrs array */
 	unsigned int lbs_tun_dev;
 	unsigned int lbs_bdev;
+	unsigned int lbs_mnt_opts;
 };
 
 /*
diff --git a/security/lsm_init.c b/security/lsm_init.c
index c2ef4db055db..26c9bdd5f851 100644
--- a/security/lsm_init.c
+++ b/security/lsm_init.c
@@ -318,6 +318,7 @@ static void __init lsm_prep_single(struct lsm_info *lsm)
 	lsm_blob_size_update(&blobs->lbs_xattr_count,
 			     &blob_sizes.lbs_xattr_count);
 	lsm_blob_size_update(&blobs->lbs_bdev, &blob_sizes.lbs_bdev);
+	lsm_blob_size_update(&blobs->lbs_mnt_opts, &blob_sizes.lbs_mnt_opts);
 }
 
 /**
@@ -459,6 +460,7 @@ int __init security_init(void)
 		lsm_pr("blob(tun_dev) size %d\n", blob_sizes.lbs_tun_dev);
 		lsm_pr("blob(xattr) count %d\n", blob_sizes.lbs_xattr_count);
 		lsm_pr("blob(bdev) size %d\n", blob_sizes.lbs_bdev);
+		lsm_pr("blob(mnt_opts) size %d\n", blob_sizes.lbs_mnt_opts);
 	}
 
 	if (blob_sizes.lbs_file)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index b00c2627286a..88cd1d56081a 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -7160,6 +7160,7 @@ struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
 	.lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
 	.lbs_tun_dev = sizeof(struct tun_security_struct),
 	.lbs_ib = sizeof(struct ib_security_struct),
+	.lbs_mnt_opts = sizeof(struct selinux_mnt_opts),
 };
 
 #ifdef CONFIG_PERF_EVENTS
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 46ef5ece991c..44bd92410425 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -5030,6 +5030,7 @@ struct lsm_blob_sizes smack_blob_sizes __ro_after_init = {
 	.lbs_sock = sizeof(struct socket_smack),
 	.lbs_superblock = sizeof(struct superblock_smack),
 	.lbs_xattr_count = SMACK_INODE_INIT_XATTRS,
+	.lbs_mnt_opts = sizeof(struct smack_mnt_opts),
 };
 
 static const struct lsm_id smack_lsmid = {
-- 
2.47.0

On Jun 17, 2025 Casey Schaufler <casey@schaufler-ca.com> wrote:
> 
> Add mount option data to the blob size accounting in anticipation
> of using a shared mnt_opts blob.
> 
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
> ---
>  include/linux/lsm_hooks.h  | 1 +
>  security/lsm_init.c        | 2 ++
>  security/selinux/hooks.c   | 1 +
>  security/smack/smack_lsm.c | 1 +
>  4 files changed, 5 insertions(+)

Since you're respinning this patchset for other reasons, just base it
on the existing LSM initialization code.  If this patchset collides with
the init rework mid-flight I'll handle the merge fixup.

I appreciate the consideration, but in this case I think it's easier to
not have the dependency.

--
paul-moore.com