From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4BA742EAE5; Thu, 11 Apr 2024 10:06:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712829962; cv=none; b=MlhhF9Ta1VKUIS6Yaca1CmkZJbxQ9Y9bouT2nuyeACN2iCYkPLnHrTklTr6hO9YKO+m8eVIv10zgc8npQxfS376ekMvnukkT7CX2XZoBE5Lywm76oAXpkCIgk6AO+DqGMrxz0OIDb3qVAJC8tHTxKozDZ3/9QDGK9uanYtFrEHo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712829962; c=relaxed/simple; bh=kKFhvrzyuZxKDJKNbB0W9W2I59yzak06BxWVhP7JPeo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Fl247f6r0aXcrWUecu0SU9gruWzEo0ycL6Rymb/PLKMwywUR5GDkZV9Fkkf8UU6dyDosUjJIRQ0afCOl4wL6HVFxgqdsgDtg8sXVAVrne3GQ1/qYDniEp39OGUftID0EcGVBa/FPz1XOhP7N0X9rYusPoX8ww0crUSL4IA4g5fE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dIzpDvJ7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="dIzpDvJ7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C576BC433F1; Thu, 11 Apr 2024 10:06:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712829962; bh=kKFhvrzyuZxKDJKNbB0W9W2I59yzak06BxWVhP7JPeo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dIzpDvJ7XKAVE+PpTpTdX4AtuEZ2GQQFOwGNAk8pLiqSGdcXE7wS6NfNn3dTvgAQb uOYWs5UE2nKGcaRX/cLFMdGCVdcvTLY6acB7hvQLT+squ/oNHZFj8QCt0Li0uHKLYI fTUOtTQqVWKnsgFFkqcVyp0TVjrF7YSpFaHXAqAU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzkaller , Kuniyuki Iwashima , Eric Dumazet , David Ahern , Jakub Kicinski Subject: [PATCH 4.19 126/175] ipv6: Fix infinite recursion in fib6_dump_done(). Date: Thu, 11 Apr 2024 11:55:49 +0200 Message-ID: <20240411095423.358935956@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240411095419.532012976@linuxfoundation.org> References: <20240411095419.532012976@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kuniyuki Iwashima commit d21d40605bca7bd5fc23ef03d4c1ca1f48bc2cae upstream. syzkaller reported infinite recursive calls of fib6_dump_done() during netlink socket destruction. [1] >>From the log, syzkaller sent an AF_UNSPEC RTM_GETROUTE message, and then the response was generated. The following recvmmsg() resumed the dump for IPv6, but the first call of inet6_dump_fib() failed at kzalloc() due to the fault injection. [0] 12:01:34 executing program 3: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route(r0, ... snip ...) recvmmsg(r0, ... snip ...) (fail_nth: 8) Here, fib6_dump_done() was set to nlk_sk(sk)->cb.done, and the next call of inet6_dump_fib() set it to nlk_sk(sk)->cb.args[3]. syzkaller stopped receiving the response halfway through, and finally netlink_sock_destruct() called nlk_sk(sk)->cb.done(). fib6_dump_done() calls fib6_dump_end() and nlk_sk(sk)->cb.done() if it is still not NULL. fib6_dump_end() rewrites nlk_sk(sk)->cb.done() by nlk_sk(sk)->cb.args[3], but it has the same function, not NULL, calling itself recursively and hitting the stack guard page. To avoid the issue, let's set the destructor after kzalloc(). [0]: FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 432110 Comm: syz-executor.3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl (lib/dump_stack.c:117) should_fail_ex (lib/fault-inject.c:52 lib/fault-inject.c:153) should_failslab (mm/slub.c:3733) kmalloc_trace (mm/slub.c:3748 mm/slub.c:3827 mm/slub.c:3992) inet6_dump_fib (./include/linux/slab.h:628 ./include/linux/slab.h:749 net/ipv6/ip6_fib.c:662) rtnl_dump_all (net/core/rtnetlink.c:4029) netlink_dump (net/netlink/af_netlink.c:2269) netlink_recvmsg (net/netlink/af_netlink.c:1988) ____sys_recvmsg (net/socket.c:1046 net/socket.c:2801) ___sys_recvmsg (net/socket.c:2846) do_recvmmsg (net/socket.c:2943) __x64_sys_recvmmsg (net/socket.c:3041 net/socket.c:3034 net/socket.c:3034) [1]: BUG: TASK stack guard page was hit at 00000000f2fa9af1 (stack is 00000000b7912430..000000009a436beb) stack guard page: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 223719 Comm: kworker/1:3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Workqueue: events netlink_sock_destruct_work RIP: 0010:fib6_dump_done (net/ipv6/ip6_fib.c:570) Code: 3c 24 e8 f3 e9 51 fd e9 28 fd ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 41 57 41 56 41 55 41 54 55 48 89 fd <53> 48 8d 5d 60 e8 b6 4d 07 fd 48 89 da 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc9000d980000 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffffffff84405990 RCX: ffffffff844059d3 RDX: ffff8881028e0000 RSI: ffffffff84405ac2 RDI: ffff88810c02f358 RBP: ffff88810c02f358 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000224 R12: 0000000000000000 R13: ffff888007c82c78 R14: ffff888007c82c68 R15: ffff888007c82c68 FS: 0000000000000000(0000) GS:ffff88811b100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc9000d97fff8 CR3: 0000000102309002 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: <#DF> fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1)) fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1)) ... fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1)) fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1)) netlink_sock_destruct (net/netlink/af_netlink.c:401) __sk_destruct (net/core/sock.c:2177 (discriminator 2)) sk_destruct (net/core/sock.c:2224) __sk_free (net/core/sock.c:2235) sk_free (net/core/sock.c:2246) process_one_work (kernel/workqueue.c:3259) worker_thread (kernel/workqueue.c:3329 kernel/workqueue.c:3416) kthread (kernel/kthread.c:388) ret_from_fork (arch/x86/kernel/process.c:153) ret_from_fork_asm (arch/x86/entry/entry_64.S:256) Modules linked in: Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzkaller Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20240401211003.25274-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_fib.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -587,19 +587,19 @@ static int inet6_dump_fib(struct sk_buff if (!w) { /* New dump: * - * 1. hook callback destructor. - */ - cb->args[3] = (long)cb->done; - cb->done = fib6_dump_done; - - /* - * 2. allocate and initialize walker. + * 1. allocate and initialize walker. */ w = kzalloc(sizeof(*w), GFP_ATOMIC); if (!w) return -ENOMEM; w->func = fib6_dump_node; cb->args[2] = (long)w; + + /* 2. hook callback destructor. + */ + cb->args[3] = (long)cb->done; + cb->done = fib6_dump_done; + } arg.skb = skb;