LSM: lift parsing LSM options into the caller of ->sb_kern_mount()

This paves the way for retaining the LSM options from a common filesystem
mount context during a mount parameter parsing phase to be instituted prior
to actual mount/reconfiguration actions.

Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 16 insertions, 8 deletions

diff --git a/fs/super.c b/fs/super.c
index 6654de035893..8d9c9199832d 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1246,17 +1246,26 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
 {
         struct dentry *root;
         struct super_block *sb;
-        char *secdata = NULL;
         int error = -ENOMEM;
+        struct security_mnt_opts opts;
+
+        security_init_mnt_opts(&opts);
 
         if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
-                secdata = alloc_secdata();
+                char *secdata = alloc_secdata();
                 if (!secdata)
-                        goto out;
+                        return ERR_PTR(-ENOMEM);
 
                 error = security_sb_copy_data(data, secdata);
+                if (error) {
+                        free_secdata(secdata);
+                        return ERR_PTR(error);
+                }
+
+                error = security_sb_parse_opts_str(secdata, &opts);
+                free_secdata(secdata);
                 if (error)
-                        goto out_free_secdata;
+                        return ERR_PTR(error);
         }
 
         root = type->mount(type, flags, name, data);
@@ -1277,7 +1286,7 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
         smp_wmb();
         sb->s_flags |= SB_BORN;
 
-        error = security_sb_kern_mount(sb, flags, secdata);
+        error = security_sb_kern_mount(sb, flags, &opts);
         if (error)
                 goto out_sb;
 
@@ -1291,14 +1300,13 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
                 "negative value (%lld)\n", type->name, sb->s_maxbytes);
 
         up_write(&sb->s_umount);
-        free_secdata(secdata);
+        security_free_mnt_opts(&opts);
         return root;
 out_sb:
         dput(root);
         deactivate_locked_super(sb);
 out_free_secdata:
-        free_secdata(secdata);
-out:
+        security_free_mnt_opts(&opts);
         return ERR_PTR(error);
 }