From 5e29dc36bd5e2166b834ceb19990d9e68a734d7d Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Fri, 30 Dec 2022 13:24:38 +0100 Subject: netfilter: ipset: Rework long task execution when adding/deleting entries When adding/deleting large number of elements in one step in ipset, it can take a reasonable amount of time and can result in soft lockup errors. The patch 5f7b51bf09ba ("netfilter: ipset: Limit the maximal range of consecutive elements to add/delete") tried to fix it by limiting the max elements to process at all. However it was not enough, it is still possible that we get hung tasks. Lowering the limit is not reasonable, so the approach in this patch is as follows: rely on the method used at resizing sets and save the state when we reach a smaller internal batch limit, unlock/lock and proceed from the saved state. Thus we can avoid long continuous tasks and at the same time removed the limit to add/delete large number of elements in one step. The nfnl mutex is held during the whole operation which prevents one to issue other ipset commands in parallel. Fixes: 5f7b51bf09ba ("netfilter: ipset: Limit the maximal range of consecutive elements to add/delete") Reported-by: syzbot+9204e7399656300bf271@syzkaller.appspotmail.com Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso --- include/linux/netfilter/ipset/ip_set.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/netfilter') diff --git a/include/linux/netfilter/ipset/ip_set.h b/include/linux/netfilter/ipset/ip_set.h index ab934ad951a8..e8c350a3ade1 100644 --- a/include/linux/netfilter/ipset/ip_set.h +++ b/include/linux/netfilter/ipset/ip_set.h @@ -197,7 +197,7 @@ struct ip_set_region { }; /* Max range where every element is added/deleted in one step */ -#define IPSET_MAX_RANGE (1<<20) +#define IPSET_MAX_RANGE (1<<14) /* The max revision number supported by any set type + 1 */ #define IPSET_REVISION_MAX 9 -- cgit