From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:237:300::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20D80A5 for ; Wed, 13 Dec 2023 02:10:09 -0800 (PST) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1rDMBr-00074R-Km; Wed, 13 Dec 2023 11:10:07 +0100 From: Florian Westphal To: Cc: Florian Westphal Subject: [PATCH nft] parser_bison: close chain scope before chain release Date: Wed, 13 Dec 2023 11:09:58 +0100 Message-ID: <20231213101002.11673-1-fw@strlen.de> X-Mailer: git-send-email 2.41.0 Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- 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 e1addc26d20d..44d440f762e7 100644 --- a/src/parser_bison.y +++ b/src/parser_bison.y @@ -1419,6 +1419,7 @@ 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, &$2, &@$, $5); } | RULE ruleid_spec diff --git a/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal b/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal new file mode 100644 index 000000000000..bb9632b053be --- /dev/null +++ b/tests/shell/testcases/bogons/nft-f/use_after_free_on_chain_removal @@ -0,0 +1,5 @@ +delete chain d iUi { +}} +delete chain d hUi { +delete chain o +c b icmpv6 id$i -- 2.41.0