On 2024/10/29 2:24, Kuniyuki Iwashima wrote:

From: Jinjie Ruan <redacted>
Date: Mon, 28 Oct 2024 16:05:15 +0800

quoted

In the error path of netlink_proto_init(), frees the already allocated
bucket table for new hash tables in a loop, but the loop condition
terminates when the index reaches zero, which fails to free the first
bucket table at index zero.

Check for >= 0 so that nl_table[0].hash is freed as well.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jinjie Ruan <redacted>
---
 net/netlink/af_netlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 0a9287fadb47..9601b85dda95 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c

@@ -2936,7 +2936,7 @@ static int __init netlink_proto_init(void)
 	for (i = 0; i < MAX_LINKS; i++) {
 		if (rhashtable_init(&nl_table[i].hash,
 				    &netlink_rhashtable_params) < 0) {
-			while (--i > 0)
+			while (--i >= 0)
 				rhashtable_destroy(&nl_table[i].hash);
 			kfree(nl_table);
 			goto panic;

I remember the same question was posted in the past.
https://lore.kernel.org/netdev/ZfOalln%2FmyRNOkH6@cy-server/ (local)

As Eric alreday pointed out (and as mentioned in the thread above too),
it's going to panic, and we need not clean up resources here, so let's
remove rhashtable_destroy() and kfree() instead of adjusting the loop
condition.

Thank you very much, remove it is fine.