[PATCH nft 2/2] netlink: add and use _nftnl_udata_buf_alloc() helper

[Thomas Haller <thaller@redhat.com>]

We don't want to handle allocation errors, but crash via memory_allocation_error().
Also, we usually just allocate NFT_USERDATA_MAXLEN buffers.

Add a helper for that and use it.

Signed-off-by: Thomas Haller <thaller@redhat.com>
---
 include/netlink.h       |  3 +++
 src/mnl.c               | 16 ++++------------
 src/netlink.c           |  7 ++-----
 src/netlink_linearize.c |  4 +---
 4 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/include/netlink.h b/include/netlink.h
index 6766d7e8563f..15cbb332c8dd 100644
--- a/include/netlink.h
+++ b/include/netlink.h
@@ -260,4 +260,7 @@ struct nft_expr_loc *nft_expr_loc_find(const struct nftnl_expr *nle,
 
 struct dl_proto_ctx *dl_proto_ctx(struct rule_pp_ctx *ctx);
 
+#define _nftnl_udata_buf_alloc() \
+	memory_allocation_check(nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN))
+
 #endif /* NFTABLES_NETLINK_H */
diff --git a/src/mnl.c b/src/mnl.c
index 0fb36bd588ee..1263c611cd20 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -823,9 +823,7 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, struct cmd *cmd,
 					    CHAIN_F_HW_OFFLOAD);
 		}
 		if (cmd->chain->comment) {
-			udbuf = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-			if (!udbuf)
-				memory_allocation_error();
+			udbuf = _nftnl_udata_buf_alloc();
 			if (!nftnl_udata_put_strz(udbuf, NFTNL_UDATA_CHAIN_COMMENT, cmd->chain->comment))
 				memory_allocation_error();
 			nftnl_chain_set_data(nlc, NFTNL_CHAIN_USERDATA, nftnl_udata_buf_data(udbuf),
@@ -1057,9 +1055,7 @@ int mnl_nft_table_add(struct netlink_ctx *ctx, struct cmd *cmd,
 		nftnl_table_set_u32(nlt, NFTNL_TABLE_FLAGS, cmd->table->flags);
 
 		if (cmd->table->comment) {
-			udbuf = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-			if (!udbuf)
-				memory_allocation_error();
+			udbuf = _nftnl_udata_buf_alloc();
 			if (!nftnl_udata_put_strz(udbuf, NFTNL_UDATA_TABLE_COMMENT, cmd->table->comment))
 				memory_allocation_error();
 			nftnl_table_set_data(nlt, NFTNL_TABLE_USERDATA, nftnl_udata_buf_data(udbuf),
@@ -1256,9 +1252,7 @@ int mnl_nft_set_add(struct netlink_ctx *ctx, struct cmd *cmd,
 		nftnl_set_set_u32(nls, NFTNL_SET_DESC_SIZE, set->init->size);
 	}
 
-	udbuf = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-	if (!udbuf)
-		memory_allocation_error();
+	udbuf = _nftnl_udata_buf_alloc();
 	if (!nftnl_udata_put_u32(udbuf, NFTNL_UDATA_SET_KEYBYTEORDER,
 				 set->key->byteorder))
 		memory_allocation_error();
@@ -1453,9 +1447,7 @@ int mnl_nft_obj_add(struct netlink_ctx *ctx, struct cmd *cmd,
 	nftnl_obj_set_u32(nlo, NFTNL_OBJ_TYPE, obj->type);
 
 	if (obj->comment) {
-		udbuf = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-		if (!udbuf)
-			memory_allocation_error();
+		udbuf = _nftnl_udata_buf_alloc();
 		if (!nftnl_udata_put_strz(udbuf, NFTNL_UDATA_OBJ_COMMENT, obj->comment))
 			memory_allocation_error();
 		nftnl_obj_set_data(nlo, NFTNL_OBJ_USERDATA, nftnl_udata_buf_data(udbuf),
diff --git a/src/netlink.c b/src/netlink.c
index 120a8ba9ceb1..0c858065ca15 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -175,11 +175,8 @@ struct nftnl_set_elem *alloc_nftnl_setelem(const struct expr *set,
 						netlink_gen_stmt_stateful(stmt));
 		}
 	}
-	if (elem->comment || expr->elem_flags) {
-		udbuf = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-		if (!udbuf)
-			memory_allocation_error();
-	}
+	if (elem->comment || expr->elem_flags)
+		udbuf = _nftnl_udata_buf_alloc();
 	if (elem->comment) {
 		if (!nftnl_udata_put_strz(udbuf, NFTNL_UDATA_SET_ELEM_COMMENT,
 					  elem->comment))
diff --git a/src/netlink_linearize.c b/src/netlink_linearize.c
index 0c62341112d8..b5adc4d186c8 100644
--- a/src/netlink_linearize.c
+++ b/src/netlink_linearize.c
@@ -1760,9 +1760,7 @@ void netlink_linearize_rule(struct netlink_ctx *ctx,
 	if (rule->comment) {
 		struct nftnl_udata_buf *udata;
 
-		udata = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
-		if (!udata)
-			memory_allocation_error();
+		udata = _nftnl_udata_buf_alloc();
 
 		if (!nftnl_udata_put_strz(udata, NFTNL_UDATA_RULE_COMMENT,
 					  rule->comment))
-- 
2.41.0