From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
In preparation for removing security_old_inode_init_security(), switch to
security_inode_init_security().
Extend the existing ocfs2_initxattrs() to take the
ocfs2_security_xattr_info structure from fs_info, and populate the
name/value/len triple with the first xattr provided by LSMs.
As fs_info was not used before, ocfs2_initxattrs() can now handle the case
of replicating the behavior of security_old_inode_init_security(), i.e.
just obtaining the xattr, in addition to setting all xattrs provided by
LSMs.
Supporting multiple xattrs is not currently supported where
security_old_inode_init_security() was called (mknod, symlink), as it
requires non-trivial changes that can be done at a later time. Like for
reiserfs, even if EVM is invoked, it will not provide an xattr (if it is
not the first to set it, its xattr will be discarded; if it is the first,
it does not have xattrs to calculate the HMAC on).
Finally, since security_inode_init_security(), unlike
security_old_inode_init_security(), returns zero instead of -EOPNOTSUPP if
no xattrs were provided by LSMs or if inodes are private, additionally
check in ocfs2_init_security_get() if the xattr name is set.
If not, act as if security_old_inode_init_security() returned -EOPNOTSUPP,
and set si->enable to zero to notify to the functions following
ocfs2_init_security_get() that no xattrs are available.
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Reviewed-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
Acked-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
---
fs/ocfs2/namei.c | 2 ++
fs/ocfs2/xattr.c | 30 ++++++++++++++++++++++++++----
2 files changed, 28 insertions(+), 4 deletions(-)
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 9175dbc4720..17c52225b87 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -242,6 +242,7 @@ static int ocfs2_mknod(struct mnt_idmap *idmap,
int want_meta = 0;
int xattr_credits = 0;
struct ocfs2_security_xattr_info si = {
+ .name = NULL,
.enable = 1,
};
int did_quota_inode = 0;
@@ -1805,6 +1806,7 @@ static int ocfs2_symlink(struct mnt_idmap *idmap,
int want_clusters = 0;
int xattr_credits = 0;
struct ocfs2_security_xattr_info si = {
+ .name = NULL,
.enable = 1,
};
int did_quota = 0, did_quota_inode = 0;
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 389308efe85..469ec45baee 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7259,9 +7259,21 @@ static int ocfs2_xattr_security_set(const struct xattr_handler *handler,
static int ocfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
void *fs_info)
{
+ struct ocfs2_security_xattr_info *si = fs_info;
const struct xattr *xattr;
int err = 0;
+ if (si) {
+ si->value = kmemdup(xattr_array->value, xattr_array->value_len,
+ GFP_KERNEL);
+ if (!si->value)
+ return -ENOMEM;
+
+ si->name = xattr_array->name;
+ si->value_len = xattr_array->value_len;
+ return 0;
+ }
+
for (xattr = xattr_array; xattr->name != NULL; xattr++) {
err = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
xattr->name, xattr->value,
@@ -7277,13 +7289,23 @@ int ocfs2_init_security_get(struct inode *inode,
const struct qstr *qstr,
struct ocfs2_security_xattr_info *si)
{
+ int ret;
+
/* check whether ocfs2 support feature xattr */
if (!ocfs2_supports_xattr(OCFS2_SB(dir->i_sb)))
return -EOPNOTSUPP;
- if (si)
- return security_old_inode_init_security(inode, dir, qstr,
- &si->name, &si->value,
- &si->value_len);
+ if (si) {
+ ret = security_inode_init_security(inode, dir, qstr,
+ &ocfs2_initxattrs, si);
+ /*
+ * security_inode_init_security() does not return -EOPNOTSUPP,
+ * we have to check the xattr ourselves.
+ */
+ if (!ret && !si->name)
+ si->enable = 0;
+
+ return ret;
+ }
return security_inode_init_security(inode, dir, qstr,
&ocfs2_initxattrs, NULL);
--
2.25.1
