From: Steve Hill <steve@opendium.com>
To: netfilter-devel@vger.kernel.org
Subject: [PATCH] netfilter: No increment ctx->level for NFT_GOTO
Date: Fri, 28 Aug 2020 17:20:59 +0100 [thread overview]
Message-ID: <231a0c69-60b1-0b18-0ed6-fcf7a9058ff0@opendium.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 2148 bytes --]
nft_immediate_validate() and nft_lookup_validate_setelem() treat
NFT_GOTO and NFT_JUMP identically, incrementing pctx->level for both.
This results in a -EMLINK ("Too many links") being unexpectedly returned
for rulesets that use lots of gotos.
This fixes this problem by not incrementing pctx->level when following
gotos.
Fixes: https://bugzilla.netfilter.org/show_bug.cgi?id=1459
Signed-off-by: Steve Hill <steve@opendium.com>
---
diff -urN
linux-4.18.0-193.14.2.el8.x86_64.vanilla/net/netfilter/nft_immediate.c
linux-4.18.0-193.14.2.el8.x86_64.opendium/net/netfilter/nft_immediate.c
---
linux-4.18.0-193.14.2.el8.x86_64.vanilla/net/netfilter/nft_immediate.c
2020-07-19 15:03:44.000000000 +0100
+++
linux-4.18.0-193.14.2.el8.x86_64.opendium/net/netfilter/nft_immediate.c
2020-08-26 15:39:47.004754668 +0100
@@ -113,13 +113,19 @@
switch (data->verdict.code) {
case NFT_JUMP:
- case NFT_GOTO:
pctx->level++;
err = nft_chain_validate(ctx, data->verdict.chain);
if (err < 0)
return err;
pctx->level--;
break;
+ case NFT_GOTO:
+ err = nft_chain_validate(ctx, data->verdict.chain);
+ if (err < 0)
+ return err;
+ break;
default:
break;
}
diff -urN
linux-4.18.0-193.14.2.el8.x86_64.vanilla/net/netfilter/nft_lookup.c
linux-4.18.0-193.14.2.el8.x86_64.opendium/net/netfilter/nft_lookup.c
--- linux-4.18.0-193.14.2.el8.x86_64.vanilla/net/netfilter/nft_lookup.c
2020-07-19 15:03:44.000000000 +0100
+++ linux-4.18.0-193.14.2.el8.x86_64.opendium/net/netfilter/nft_lookup.c
2020-08-26 15:42:35.885223417 +0100
@@ -176,13 +176,19 @@
data = nft_set_ext_data(ext);
switch (data->verdict.code) {
case NFT_JUMP:
- case NFT_GOTO:
pctx->level++;
err = nft_chain_validate(ctx, data->verdict.chain);
if (err < 0)
return err;
pctx->level--;
break;
+ case NFT_GOTO:
+ err = nft_chain_validate(ctx, data->verdict.chain);
+ if (err < 0)
+ return err;
+ break;
default:
break;
}
[-- Attachment #2: steve.vcf --]
[-- Type: text/x-vcard, Size: 259 bytes --]
begin:vcard
fn:Steve Hill
n:Hill;Steve
org:Opendium Limited
adr:1 Brue Close;;Highfield House;Bruton;Somerset;BA10 0HY;England
email;internet:steve@opendium.com
title:Technical Director
x-mozilla-html:FALSE
url:https://www.opendium.com
version:2.1
end:vcard
reply other threads:[~2020-08-28 16:58 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=231a0c69-60b1-0b18-0ed6-fcf7a9058ff0@opendium.com \
--to=steve@opendium.com \
--cc=netfilter-devel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).