nftables/0077-mnl-do-not-use-expr-identifier-to-fetch-device-name.patch
2023-02-27 14:33:43 -05:00

131 lines
4.1 KiB
Diff

From 2747cab9c49b570347c86ff59daec93a1432b0bc Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Wed, 27 Apr 2022 14:37:00 +0200
Subject: [PATCH] mnl: do not use expr->identifier to fetch device name
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2070924
Upstream Status: nftables commit 78bbe7f7a55be
commit 78bbe7f7a55be48909067e25900de27623d8fa6a
Author: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Wed Feb 19 21:05:26 2020 +0100
mnl: do not use expr->identifier to fetch device name
This string might not be nul-terminated, resulting in spurious errors
when adding netdev chains.
Fixes: 3fdc7541fba0 ("src: add multidevice support for netdev chain")
Fixes: 92911b362e90 ("src: add support to add flowtables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
src/mnl.c | 33 +++++++++++++++++++++++++++++----
src/parser_bison.y | 6 +++---
2 files changed, 32 insertions(+), 7 deletions(-)
diff --git a/src/mnl.c b/src/mnl.c
index 44cf1a4..f881d97 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -26,6 +26,7 @@
#include <mnl.h>
#include <string.h>
+#include <net/if.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <fcntl.h>
@@ -529,7 +530,9 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, const struct cmd *cmd,
{
int priority, policy, i = 0;
struct nftnl_chain *nlc;
+ unsigned int ifname_len;
const char **dev_array;
+ char ifname[IFNAMSIZ];
struct nlmsghdr *nlh;
struct expr *expr;
int dev_array_len;
@@ -562,7 +565,12 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, const struct cmd *cmd,
dev_array = xmalloc(sizeof(char *) * 8);
dev_array_len = 8;
list_for_each_entry(expr, &cmd->chain->dev_expr->expressions, list) {
- dev_array[i++] = expr->identifier;
+ ifname_len = div_round_up(expr->len, BITS_PER_BYTE);
+ memset(ifname, 0, sizeof(ifname));
+ mpz_export_data(ifname, expr->value,
+ BYTEORDER_HOST_ENDIAN,
+ ifname_len);
+ dev_array[i++] = xstrdup(ifname);
if (i == dev_array_len) {
dev_array_len *= 2;
dev_array = xrealloc(dev_array,
@@ -577,6 +585,10 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, const struct cmd *cmd,
nftnl_chain_set_data(nlc, NFTNL_CHAIN_DEVICES, dev_array,
sizeof(char *) * dev_array_len);
+ i = 0;
+ while (dev_array[i] != NULL)
+ xfree(dev_array[i++]);
+
xfree(dev_array);
}
}
@@ -1488,7 +1500,9 @@ int mnl_nft_flowtable_add(struct netlink_ctx *ctx, const struct cmd *cmd,
unsigned int flags)
{
struct nftnl_flowtable *flo;
+ unsigned int ifname_len;
const char **dev_array;
+ char ifname[IFNAMSIZ];
struct nlmsghdr *nlh;
int i = 0, len = 1;
struct expr *expr;
@@ -1513,13 +1527,24 @@ int mnl_nft_flowtable_add(struct netlink_ctx *ctx, const struct cmd *cmd,
list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list)
len++;
- dev_array = calloc(len, sizeof(char *));
- list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list)
- dev_array[i++] = expr->identifier;
+ dev_array = xmalloc(sizeof(char *) * len);
+
+ list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list) {
+ ifname_len = div_round_up(expr->len, BITS_PER_BYTE);
+ memset(ifname, 0, sizeof(ifname));
+ mpz_export_data(ifname, expr->value, BYTEORDER_HOST_ENDIAN,
+ ifname_len);
+ dev_array[i++] = xstrdup(ifname);
+ }
dev_array[i] = NULL;
nftnl_flowtable_set_data(flo, NFTNL_FLOWTABLE_DEVICES,
dev_array, sizeof(char *) * len);
+
+ i = 0;
+ while (dev_array[i] != NULL)
+ xfree(dev_array[i++]);
+
free(dev_array);
netlink_dump_flowtable(flo, ctx);
diff --git a/src/parser_bison.y b/src/parser_bison.y
index 2cdf8ec..dc87571 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -1909,9 +1909,9 @@ flowtable_list_expr : flowtable_expr_member
flowtable_expr_member : STRING
{
- $$ = symbol_expr_alloc(&@$, SYMBOL_VALUE,
- current_scope(state),
- $1);
+ $$ = constant_expr_alloc(&@$, &string_type,
+ BYTEORDER_HOST_ENDIAN,
+ strlen($1) * BITS_PER_BYTE, $1);
xfree($1);
}
;
--
2.34.1