| From foo@baz Tue Nov 28 10:58:31 CET 2017 |
| From: Florian Westphal <fw@strlen.de> |
| Date: Tue, 13 Dec 2016 13:59:33 +0100 |
| Subject: netfilter: nf_tables: fix oob access |
| |
| From: Florian Westphal <fw@strlen.de> |
| |
| |
| [ Upstream commit 3e38df136e453aa69eb4472108ebce2fb00b1ba6 ] |
| |
| BUG: KASAN: slab-out-of-bounds in nf_tables_rule_destroy+0xf1/0x130 at addr ffff88006a4c35c8 |
| Read of size 8 by task nft/1607 |
| |
| When we've destroyed last valid expr, nft_expr_next() returns an invalid expr. |
| We must not dereference it unless it passes != nft_expr_last() check. |
| |
| Signed-off-by: Florian Westphal <fw@strlen.de> |
| Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> |
| Signed-off-by: Sasha Levin <alexander.levin@verizon.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/netfilter/nf_tables_api.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/net/netfilter/nf_tables_api.c |
| +++ b/net/netfilter/nf_tables_api.c |
| @@ -1869,7 +1869,7 @@ static void nf_tables_rule_destroy(const |
| * is called on error from nf_tables_newrule(). |
| */ |
| expr = nft_expr_first(rule); |
| - while (expr->ops && expr != nft_expr_last(rule)) { |
| + while (expr != nft_expr_last(rule) && expr->ops) { |
| nf_tables_expr_destroy(ctx, expr); |
| expr = nft_expr_next(expr); |
| } |
