nftables/backport-tcpopt-don-t-create-exthdr-expression-without-datatype.patch
eaglegai fdda182ca0 backport upstream patches
(cherry picked from commit 0e6a0d500c190abf447a7169f540e88d79fd5f7f)
2024-09-26 15:31:23 +08:00

45 lines
1.5 KiB
Diff

From c9f934ca446de5041ce6f19e4ee6a0c74b120186 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Fri, 15 Dec 2023 13:04:22 +0100
Subject: [PATCH] tcpopt: don't create exthdr expression without datatype
The reproducer crashes during concat evaluation, as the
exthdr expression lacks a datatype.
This should never happen, i->dtype must be set.
In this case the culprit is tcp option parsing, it will
wire up a non-existent template, because the "nop" option
has no length field (1 byte only).
Signed-off-by: Florian Westphal <fw@strlen.de>
---
src/tcpopt.c | 2 +-
tests/shell/testcases/bogons/nft-f/tcp_option_without_template | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
create mode 100644 tests/shell/testcases/bogons/nft-f/tcp_option_without_template
diff --git a/src/tcpopt.c b/src/tcpopt.c
index 8111a507..f977e417 100644
--- a/src/tcpopt.c
+++ b/src/tcpopt.c
@@ -224,7 +224,7 @@ struct expr *tcpopt_expr_alloc(const struct location *loc,
}
tmpl = &desc->templates[field];
- if (!tmpl)
+ if (!tmpl || !tmpl->dtype)
return NULL;
expr = expr_alloc(loc, EXPR_EXTHDR, tmpl->dtype,
diff --git a/tests/shell/testcases/bogons/nft-f/tcp_option_without_template b/tests/shell/testcases/bogons/nft-f/tcp_option_without_template
new file mode 100644
index 00000000..fd732fd3
--- /dev/null
+++ b/tests/shell/testcases/bogons/nft-f/tcp_option_without_template
@@ -0,0 +1 @@
+add rule f i tcp option nop length . @ih,32,3 1
--
2.33.0