(fold up) move cap_convert_nscap to setxattr2017-04-24/nsfscaps

rename cap_convert_nscap (rename in updated commit msg)

Signed-off-by: Serge Hallyn <serge@hallyn.com>

3 files changed, 13 insertions, 20 deletions

diff --git a/fs/xattr.c b/fs/xattr.c
index e3593c998c21ab..601f627c8e448f 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -445,17 +445,9 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 		    (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
 			posix_acl_fix_xattr_from_user(kvalue, size);
 		else if (strcmp(kname, XATTR_NAME_CAPS) == 0) {
-			char *wvalue = NULL;
-			size_t wsize;
-			error = cap_setxattr_convert_nscap(d, kvalue, size,
-			                                   &wvalue, &wsize);
+			error = cap_convert_nscap(d, &kvalue, &size);
 			if (error < 0)
 				goto out;
-			if (wvalue) {
-				kvfree(kvalue);
-				kvalue = wvalue;
-				size = wsize;
-			}
 		}
 	}
 
diff --git a/include/linux/capability.h b/include/linux/capability.h
index c47febf8448b50..e5fafc9b3ea2b2 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -247,7 +247,6 @@ extern bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns);
 /* audit system wants to get cap info from files as well */
 extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);
 
-extern int cap_setxattr_convert_nscap(struct dentry *dentry, const void *value,
-		size_t size, void **wvalue, size_t *wsize);
+extern int cap_convert_nscap(struct dentry *dentry, void **value, size_t *size);
 
 #endif /* !_LINUX_CAPABILITY_H */
diff --git a/security/commoncap.c b/security/commoncap.c
index 37fab19d9b3b59..91a632183c497a 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -456,14 +456,12 @@ static kuid_t rootid_from_xattr(const void *value, size_t size,
 }
 
 /*
- * User requested a write of security.capability.
+ * User requested a write of security.capability.  If needed, update the
+ * xattr to change from v2 to v3, or to fixup the v3 rootid.
  *
- * If all is ok, we return 0.  If the capability needs to be converted,
- * wvalue will be allocated (and needs to be freed) with the new value.
- * On error, return < 0.
+ * If all is ok, we return 0, on error return < 0.
  */
-int cap_setxattr_convert_nscap(struct dentry *dentry, const void *value, size_t size,
-				    void **wvalue, size_t *wsize)
+int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t *isize)
 {
 	struct vfs_ns_cap_data *nscap;
 	uid_t nsrootid;
@@ -473,6 +471,8 @@ int cap_setxattr_convert_nscap(struct dentry *dentry, const void *value, size_t
 	struct user_namespace *task_ns = current_user_ns(),
 		*fs_ns = inode->i_sb->s_user_ns;
 	kuid_t rootid;
+	size_t size = *isize, newsize;
+	void *value = *ivalue;
 
 	if (!value)
 		return -EINVAL;
@@ -499,8 +499,8 @@ int cap_setxattr_convert_nscap(struct dentry *dentry, const void *value, size_t
 	if (nsrootid == -1)
 		return -EINVAL;
 
-	*wsize = sizeof(struct vfs_ns_cap_data);
-	nscap = kmalloc(*wsize, GFP_ATOMIC);
+	newsize = sizeof(struct vfs_ns_cap_data);
+	nscap = kmalloc(newsize, GFP_ATOMIC);
 	if (!nscap)
 		return -ENOMEM;
 	nscap->rootid = cpu_to_le32(nsrootid);
@@ -511,7 +511,9 @@ int cap_setxattr_convert_nscap(struct dentry *dentry, const void *value, size_t
 	nscap->magic_etc = cpu_to_le32(nsmagic);
 	memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
 
-	*wvalue = nscap;
+	kvfree(*ivalue);
+	*ivalue = nscap;
+	*isize = newsize;
 	return 0;
 }