Blob Blame History Raw
From 55b7c71dce7144f4dc0297c17abf0f04879ee247 Mon Sep 17 00:00:00 2001
From: Phil Sutter <phil@nwl.cc>
Date: Tue, 17 Nov 2020 11:38:27 +0100
Subject: [iptables PATCH] ebtables: Fix for broken chain renaming

Loading extensions pollutes 'errno' value, hence before using it to
indicate failure it should be sanitized. This was done by the called
function before the parsing/netlink split and not migrated by accident.
Move it into calling code to clarify the connection.

Fixes: a7f1e208cdf9c ("nft: split parsing from netlink commands")
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 iptables/nft.c                                                | 3 ---
 iptables/tests/shell/testcases/ebtables/0001-ebtables-basic_0 | 4 ++++
 iptables/xtables-eb.c                                         | 1 +
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/iptables/nft.c b/iptables/nft.c
index 39882a443a974..411e2597205c9 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -1896,9 +1896,6 @@ int nft_chain_user_rename(struct nft_handle *h,const char *chain,
 		return 0;
 	}
 
-	/* Config load changed errno. Ensure genuine info for our callers. */
-	errno = 0;
-
 	/* Find the old chain to be renamed */
 	c = nft_chain_find(h, table, chain);
 	if (c == NULL) {
diff --git a/iptables/tests/shell/testcases/ebtables/0001-ebtables-basic_0 b/iptables/tests/shell/testcases/ebtables/0001-ebtables-basic_0
index 0c1eb4ca66f52..6f11bd12593dd 100755
--- a/iptables/tests/shell/testcases/ebtables/0001-ebtables-basic_0
+++ b/iptables/tests/shell/testcases/ebtables/0001-ebtables-basic_0
@@ -86,4 +86,8 @@ if [ $? -eq 0 ]; then
 	exit 1
 fi
 
+$XT_MULTI ebtables -t filter -E FOO BAZ || exit 1
+$XT_MULTI ebtables -t filter -L | grep -q FOO && exit 1
+$XT_MULTI ebtables -t filter -L | grep -q BAZ || exit 1
+
 $XT_MULTI ebtables -t $t -F || exit 0
diff --git a/iptables/xtables-eb.c b/iptables/xtables-eb.c
index 6641a21a72d32..5e4184b8e80de 100644
--- a/iptables/xtables-eb.c
+++ b/iptables/xtables-eb.c
@@ -853,6 +853,7 @@ int do_commandeb(struct nft_handle *h, int argc, char *argv[], char **table,
 				else if (strchr(argv[optind], ' ') != NULL)
 					xtables_error(PARAMETER_PROBLEM, "Use of ' ' not allowed in chain names");
 
+				errno = 0;
 				ret = nft_cmd_chain_user_rename(h, chain, *table,
 							    argv[optind]);
 				if (ret != 0 && errno == ENOENT)
-- 
2.28.0