Re: [PATCH net] netlink: Fix off-by-one error in netlink_proto_init()
From: Kuniyuki Iwashima <hidden>
Date: 2024-10-28 18:24:31
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From: Jinjie Ruan <redacted> Date: Mon, 28 Oct 2024 16:05:15 +0800
quoted hunk ↗ jump to hunk
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.