On Fri, 24 Feb 2012 19:19:22 -0800 (PST)
Hugh Dickins [off-list ref] wrote:

+/*
+ * Callback for security_inode_init_security() for acquiring xattrs.
+ */
+static int shmem_initxattrs(struct inode *inode,
+			    const struct xattr *xattr_array,
+			    void *fs_info)
+{
+	struct shmem_inode_info *info = SHMEM_I(inode);
+	const struct xattr *xattr;
+	struct shmem_xattr *new_xattr;
+	size_t len;
+
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+		new_xattr = shmem_xattr_alloc(xattr->value, xattr->value_len);
+		if (!new_xattr)
+			return -ENOMEM;
+
+		len = strlen(xattr->name) + 1;
+		new_xattr->name = kmalloc(XATTR_SECURITY_PREFIX_LEN + len,
+					  GFP_KERNEL);
+		if (!new_xattr->name) {
+			kfree(new_xattr);
+			return -ENOMEM;
+		}
+
+		memcpy(new_xattr->name, XATTR_SECURITY_PREFIX,
+		       XATTR_SECURITY_PREFIX_LEN);
+		memcpy(new_xattr->name + XATTR_SECURITY_PREFIX_LEN,
+		       xattr->name, len);
+
+		spin_lock(&info->lock);
+		list_add(&new_xattr->list, &info->xattr_list);
+		spin_unlock(&info->lock);
+	}
+
+	return 0;
+}

So if there's a kmalloc failure partway through the array, we leave a
partially xattrified inode in place.

Are we sure this is OK?

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