nftables/backport-iptopt-fix-crash-with-invalid-field-type-combo.patch
2023-03-22 16:12:03 +08:00

79 lines
2.5 KiB
Diff

From 48aca2de80a7dd73f8f3a461c7f7ed47b6082766 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Fri, 3 Dec 2021 17:07:55 +0100
Subject: iptopt: fix crash with invalid field/type combo
% nft describe ip option rr value
segmentation fault
after this fix, this exits with 'Error: unknown ip option type/field'.
Problem is that 'rr' doesn't have a value template, so the template
struct is
all-zeroes, so we crash when trying to use tmpl->dtype (its NULL).
Furthermore, expr_describe tries to print expr->identifier but expr is
exthdr, not symbol: ->identifier contains garbage.
Conflict: NA
Reference:
https://git.netfilter.org/nftables/commit/?id=48aca2de80a7dd73f8f3a461c7f7ed47b6082766
Signed-off-by: Florian Westphal <fw@strlen.de>
---
src/expression.c | 7 +++----
src/ipopt.c | 2 ++
src/parser_bison.y | 4 ++++
3 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/src/expression.c b/src/expression.c
index 4c0874f..1a88f08 100644
--- a/src/expression.c
+++ b/src/expression.c
@@ -135,12 +135,11 @@ void expr_describe(const struct expr *expr, struct output_ctx *octx)
nft_print(octx, "datatype %s (%s)",
dtype->name, dtype->desc);
len = dtype->size;
- } else if (dtype != &invalid_type) {
+ } else {
nft_print(octx, "%s expression, datatype %s (%s)",
expr_name(expr), dtype->name, dtype->desc);
- } else {
- nft_print(octx, "datatype %s is invalid\n", expr->identifier);
- return;
+ if (dtype == &invalid_type)
+ return;
}
if (dtype->basetype != NULL) {
diff --git a/src/ipopt.c b/src/ipopt.c
index 5f9f908..fdd3f93 100644
--- a/src/ipopt.c
+++ b/src/ipopt.c
@@ -97,6 +97,8 @@ struct expr *ipopt_expr_alloc(const struct location *loc, uint8_t type,
if (!tmpl)
return NULL;
+ if (!tmpl->len)
+ return NULL;
expr = expr_alloc(loc, EXPR_EXTHDR, tmpl->dtype,
BYTEORDER_BIG_ENDIAN, tmpl->len);
expr->exthdr.desc = desc;
diff --git a/src/parser_bison.y b/src/parser_bison.y
index 83f0250..65ba6a4 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -5296,6 +5296,10 @@ ip_hdr_expr : IP ip_hdr_field close_scope_ip
| IP OPTION ip_option_type ip_option_field close_scope_ip
{
$$ = ipopt_expr_alloc(&@$, $3, $4, 0);
+ if (!$$) {
+ erec_queue(error(&@1, "unknown ip option type/field"), state->msgs);
+ YYERROR;
+ }
}
| IP OPTION ip_option_type close_scope_ip
{
--
2.23.0