From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
In preparation for moving IMA and EVM to the LSM infrastructure, introduce
the inode_post_removexattr hook.
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Reviewed-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
---
fs/xattr.c | 9 +++++----
include/linux/lsm_hook_defs.h | 2 ++
include/linux/security.h | 5 +++++
security/security.c | 14 ++++++++++++++
4 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/fs/xattr.c b/fs/xattr.c
index e7bbb7f57557..4a0280295686 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap,
goto out;
error = __vfs_removexattr(idmap, dentry, name);
+ if (error)
+ goto out;
- if (!error) {
- fsnotify_xattr(dentry);
- evm_inode_post_removexattr(dentry, name);
- }
+ fsnotify_xattr(dentry);
+ security_inode_post_removexattr(dentry, name);
+ evm_inode_post_removexattr(dentry, name);
out:
return error;
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 995d30336cfa..1153e7163b8b 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name)
LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry)
LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap,
struct dentry *dentry, const char *name)
+LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry,
+ const char *name)
LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap,
struct dentry *dentry, const char *acl_name, struct posix_acl *kacl)
LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap,
diff --git a/include/linux/security.h b/include/linux/security.h
index 820899db5276..665bba3e0081 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name);
int security_inode_listxattr(struct dentry *dentry);
int security_inode_removexattr(struct mnt_idmap *idmap,
struct dentry *dentry, const char *name);
+void security_inode_post_removexattr(struct dentry *dentry, const char *name);
int security_inode_need_killpriv(struct dentry *dentry);
int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry);
int security_inode_getsecurity(struct mnt_idmap *idmap,
@@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap,
return cap_inode_removexattr(idmap, dentry, name);
}
+static inline void security_inode_post_removexattr(struct dentry *dentry,
+ const char *name)
+{ }
+
static inline int security_inode_need_killpriv(struct dentry *dentry)
{
return cap_inode_need_killpriv(dentry);
diff --git a/security/security.c b/security/security.c
index 764a6f28b3b9..3947159ba5e9 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap,
return evm_inode_removexattr(idmap, dentry, name);
}
+/**
+ * security_inode_post_removexattr() - Update the inode after a removexattr op
+ * @dentry: file
+ * @name: xattr name
+ *
+ * Update the inode after a successful removexattr operation.
+ */
+void security_inode_post_removexattr(struct dentry *dentry, const char *name)
+{
+ if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
+ return;
+ call_void_hook(inode_post_removexattr, dentry, name);
+}
+
/**
* security_inode_need_killpriv() - Check if security_inode_killpriv() required
* @dentry: associated dentry
--
2.34.1
