Commit e3eeacba authored Jan 13, 2018 by Florian Westphal Committed by Pablo Neira Ayuso Jan 16, 2018

netfilter: x_tables: don't return garbage pointer on modprobe failure



request_module may return a positive error result from modprobe,
if we cast this to ERR_PTR this returns a garbage result (it passes
IS_ERR checks).

Fix it by ignoring modprobe return values entirely, just retry the
table lookup instead.

Reported-by:  <syzbot+980925dbfbc7f93bc2ef@syzkaller.appspotmail.com>
Fixes: 03d13b68 ("netfilter: xtables: add and use xt_request_find_table_lock")
Fixes: 20651cef ("netfilter: x_tables: unbreak module auto loading")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

parent 9be9d04b

net/netfilter/x_tables.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1085,7 +1085,7 @@ struct xt_table xt_request_find_table_lock(struct net net, u_int8_t af,
		#ifdef CONFIG_MODULES
		if (IS_ERR(t)) {
		int err = request_module("%stable_%s", xt_prefix[af], name);
		if (err)
		if (err < 0)
		return ERR_PTR(err);
		t = xt_find_table_lock(net, af, name);
		}

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