nftables/SOURCES/0050-parser_bison-close-chain-scope-before-chain-release.patch
2026-08-26 08:03:54 -04:00

59 lines
2.2 KiB
Diff

From fdb03b033c3efcb28b4c51c469d3e93559d7bdb8 Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Fri, 17 Jul 2026 11:08:41 +0200
Subject: [PATCH] parser_bison: close chain scope before chain release
JIRA: https://issues.redhat.com/browse/RHEL-190549
Upstream Status: nftables commit 28b3bbec5a97aaa57f7138fee8b2f22ff0e5b960
commit 28b3bbec5a97aaa57f7138fee8b2f22ff0e5b960
Author: Florian Westphal <fw@strlen.de>
Date: Wed Dec 13 11:09:58 2023 +0100
parser_bison: close chain scope before chain release
cmd_alloc() will free the chain, so we must close the scope opened
in chain_block_alloc beforehand.
The included test file will cause a use-after-free because nft attempts
to search for an identifier in a scope that has been freed:
AddressSanitizer: heap-use-after-free on address 0x618000000368 at pc 0x7f1cbc0e6959 bp 0x7ffd3ccb7850 sp 0x7ffd3ccb7840
#0 0x7f1cbc0e6958 in symbol_lookup src/rule.c:629
#1 0x7f1cbc0e66a1 in symbol_get src/rule.c:588
#2 0x7f1cbc120d67 in nft_parse src/parser_bison.y:4325
Fixes: a66b5ad9540d ("src: allow for updating devices on existing netdev chain")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Phil Sutter <psutter@redhat.com>
---
src/parser_bison.y | 1 +
.../testcases/bogons/nft-f/use_after_free_on_chain_removal | 5 +++++
2 files changed, 6 insertions(+)
create mode 100644 tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal
diff --git a/src/parser_bison.y b/src/parser_bison.y
index 2c829f9..83302fd 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -1397,6 +1397,7 @@ delete_cmd : TABLE table_or_id_spec
{
$5->location = @5;
handle_merge(&$3->handle, &$2);
+ close_scope(state);
$$ = cmd_alloc(CMD_DELETE, CMD_OBJ_CHAIN, &$2, &@$, $5);
}
| RULE ruleid_spec
diff --git a/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal b/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal
new file mode 100644
index 0000000..bb9632b
--- /dev/null
+++ b/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal
@@ -0,0 +1,5 @@
+delete chain d iUi {
+}}
+delete chain d hUi {
+delete chain o
+c b icmpv6 id$i