libceph: handle OSD op ceph_pagelist_append() errors

osd_req_op_cls_init() and osd_req_op_xattr_init() currently propagate
ceph_pagelist_alloc() ENOMEM errors but ignore ceph_pagelist_append()
memory allocation failures. Add these checks and cleanup on error.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

net/ceph/osd_client.c

@@ -841,6 +841,7 @@ int osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
 	struct ceph_pagelist *pagelist;
 	size_t payload_len = 0;
 	size_t size;
+	int ret;
 
 	op = _osd_req_op_init(osd_req, which, CEPH_OSD_OP_CALL, 0);
 
@@ -852,20 +853,27 @@ int osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
 	size = strlen(class);
 	BUG_ON(size > (size_t) U8_MAX);
 	op->cls.class_len = size;
-	ceph_pagelist_append(pagelist, class, size);
+	ret = ceph_pagelist_append(pagelist, class, size);
+	if (ret)
+		goto err_pagelist_free;
 	payload_len += size;
 
 	op->cls.method_name = method;
 	size = strlen(method);
 	BUG_ON(size > (size_t) U8_MAX);
 	op->cls.method_len = size;
-	ceph_pagelist_append(pagelist, method, size);
+	ret = ceph_pagelist_append(pagelist, method, size);
+	if (ret)
+		goto err_pagelist_free;
 	payload_len += size;
 
 	osd_req_op_cls_request_info_pagelist(osd_req, which, pagelist);
-
 	op->indata_len = payload_len;
 	return 0;
+
+err_pagelist_free:
+	ceph_pagelist_release(pagelist);
+	return ret;
 }
 EXPORT_SYMBOL(osd_req_op_cls_init);
 
@@ -877,6 +885,7 @@ int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
 						      opcode, 0);
 	struct ceph_pagelist *pagelist;
 	size_t payload_len;
+	int ret;
 
 	BUG_ON(opcode != CEPH_OSD_OP_SETXATTR && opcode != CEPH_OSD_OP_CMPXATTR);
 
@@ -886,10 +895,14 @@ int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
 
 	payload_len = strlen(name);
 	op->xattr.name_len = payload_len;
-	ceph_pagelist_append(pagelist, name, payload_len);
+	ret = ceph_pagelist_append(pagelist, name, payload_len);
+	if (ret)
+		goto err_pagelist_free;
 
 	op->xattr.value_len = size;
-	ceph_pagelist_append(pagelist, value, size);
+	ret = ceph_pagelist_append(pagelist, value, size);
+	if (ret)
+		goto err_pagelist_free;
 	payload_len += size;
 
 	op->xattr.cmp_op = cmp_op;
@@ -898,6 +911,10 @@ int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
 	ceph_osd_data_pagelist_init(&op->xattr.osd_data, pagelist);
 	op->indata_len = payload_len;
 	return 0;
+
+err_pagelist_free:
+	ceph_pagelist_release(pagelist);
+	return ret;
 }
 EXPORT_SYMBOL(osd_req_op_xattr_init);