From bf06d5a6df59cb5e87fe5e909431da5697a965e3 Mon Sep 17 00:00:00 2001
From: Phil Sutter <phil@nwl.cc>
Date: Fri, 25 Nov 2022 21:21:22 +0100
Subject: [PATCH] nft: Plug memleak in nft_rule_zero_counters()

When zeroing a specific rule, valgrind reports:

40 bytes in 1 blocks are definitely lost in loss record 1 of 1
   at 0x484659F: calloc (vg_replace_malloc.c:1328)
   by 0x48DE128: xtables_calloc (xtables.c:434)
   by 0x11C7C6: nft_parse_immediate (nft-shared.c:1071)
   by 0x11C7C6: nft_rule_to_iptables_command_state (nft-shared.c:1236)
   by 0x119AF5: nft_rule_zero_counters (nft.c:2877)
   by 0x11A3CA: nft_prepare (nft.c:3445)
   by 0x11A7A8: nft_commit (nft.c:3479)
   by 0x114258: xtables_main.isra.0 (xtables-standalone.c:94)
   by 0x1142D9: xtables_ip6_main (xtables-standalone.c:118)
   by 0x49F2349: (below main) (in /lib64/libc.so.6)

Have to free the matches/target in populated iptables_command_state object
again. While being at it, call the proper family_ops callbacks since this is
family-agnostic code.

Fixes: a69cc575295ee ("xtables: allow to reset the counters of an existing rule")
Signed-off-by: Phil Sutter <phil@nwl.cc>
(cherry picked from commit aa0c54030300441e9fd66c7016d0090f6736d449)
---
 iptables/nft.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/iptables/nft.c b/iptables/nft.c
index 0ec7679d25289..b70e9237a04ab 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -2614,10 +2614,11 @@ int nft_rule_zero_counters(struct nft_handle *h, const char *chain,
 		goto error;
 	}
 
-	nft_rule_to_iptables_command_state(h, r, &cs);
-
+	h->ops->rule_to_cs(h, r, &cs);
 	cs.counters.pcnt = cs.counters.bcnt = 0;
 	new_rule = nft_rule_new(h, chain, table, &cs);
+	h->ops->clear_cs(&cs);
+
 	if (!new_rule)
 		return 1;
 
-- 
2.40.0