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 9ED5447A57; Mon, 1 Apr 2024 15:54:39 +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=1711986879; cv=none; b=lWexUSdqKU3K0SHE2h8BAhKsQwf9QquNthQragMlKv3WavBxSa0EWTFmHxvRyXeRYLcFpdEnt7U1sDWCwnaShELxAcv0/YcB2tzX/rhWkrL+kuWwszFfF64UtQh/OHifCGSwIjxqjyxo+AImBCm20EtjDidpLub5BQ6mmD+pdf0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711986879; c=relaxed/simple; bh=bBzRvllH2PLbqDe5zlqRYoNs4jJgL+ilJ/XFsTAiDpI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=depMR7NKuSIwJ18obZPEyneCWptixqsBQuY90Z5YU8XX4CfRBvDne7IObZNWoetIJDYPGk7nWu35yrAWur+tX9a/KdvDFOn4k2xtddFv2/sS+FbzgAqnV+N9n8wxthsQx5s+nQACtPIV3Vz9czMS8SmyAMTZmsEZ5L5ywxy6Epk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=mTyaBLD3; 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="mTyaBLD3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 200DFC43394; Mon, 1 Apr 2024 15:54:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1711986879; bh=bBzRvllH2PLbqDe5zlqRYoNs4jJgL+ilJ/XFsTAiDpI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mTyaBLD3wjRu8EFzNA+mj3obfLrYhNiWTu86QNSDFZ3FIkcWryV1+pH0fqLsZrg7G n7jZfa0GWPbzqi0/D0DqM7YG76liJhuniTCZa5VxovRzkbrqv9jKdeTwnuRbvyIWHl o5rpGzcscdtEM2Q/4NgL9kC7eUVK1QliaZpLtG4o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Fedor Pchelkin , Alexander Aring , Stefan Schmidt , Sasha Levin Subject: [PATCH 6.8 115/399] mac802154: fix llsec key resources release in mac802154_llsec_key_del Date: Mon, 1 Apr 2024 17:41:21 +0200 Message-ID: <20240401152552.623305855@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240401152549.131030308@linuxfoundation.org> References: <20240401152549.131030308@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 6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fedor Pchelkin [ Upstream commit e8a1e58345cf40b7b272e08ac7b32328b2543e40 ] mac802154_llsec_key_del() can free resources of a key directly without following the RCU rules for waiting before the end of a grace period. This may lead to use-after-free in case llsec_lookup_key() is traversing the list of keys in parallel with a key deletion: refcount_t: addition on 0; use-after-free. WARNING: CPU: 4 PID: 16000 at lib/refcount.c:25 refcount_warn_saturate+0x162/0x2a0 Modules linked in: CPU: 4 PID: 16000 Comm: wpan-ping Not tainted 6.7.0 #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:refcount_warn_saturate+0x162/0x2a0 Call Trace: llsec_lookup_key.isra.0+0x890/0x9e0 mac802154_llsec_encrypt+0x30c/0x9c0 ieee802154_subif_start_xmit+0x24/0x1e0 dev_hard_start_xmit+0x13e/0x690 sch_direct_xmit+0x2ae/0xbc0 __dev_queue_xmit+0x11dd/0x3c20 dgram_sendmsg+0x90b/0xd60 __sys_sendto+0x466/0x4c0 __x64_sys_sendto+0xe0/0x1c0 do_syscall_64+0x45/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Also, ieee802154_llsec_key_entry structures are not freed by mac802154_llsec_key_del(): unreferenced object 0xffff8880613b6980 (size 64): comm "iwpan", pid 2176, jiffies 4294761134 (age 60.475s) hex dump (first 32 bytes): 78 0d 8f 18 80 88 ff ff 22 01 00 00 00 00 ad de x......."....... 00 00 00 00 00 00 00 00 03 00 cd ab 00 00 00 00 ................ backtrace: [] __kmem_cache_alloc_node+0x1e2/0x2d0 [] kmalloc_trace+0x25/0xc0 [] mac802154_llsec_key_add+0xac9/0xcf0 [] ieee802154_add_llsec_key+0x5a/0x80 [] nl802154_add_llsec_key+0x426/0x5b0 [] genl_family_rcv_msg_doit+0x1fe/0x2f0 [] genl_rcv_msg+0x531/0x7d0 [] netlink_rcv_skb+0x169/0x440 [] genl_rcv+0x28/0x40 [] netlink_unicast+0x53c/0x820 [] netlink_sendmsg+0x93b/0xe60 [] ____sys_sendmsg+0xac5/0xca0 [] ___sys_sendmsg+0x11d/0x1c0 [] __sys_sendmsg+0xfa/0x1d0 [] do_syscall_64+0x45/0xf0 [] entry_SYSCALL_64_after_hwframe+0x6e/0x76 Handle the proper resource release in the RCU callback function mac802154_llsec_key_del_rcu(). Note that if llsec_lookup_key() finds a key, it gets a refcount via llsec_key_get() and locally copies key id from key_entry (which is a list element). So it's safe to call llsec_key_put() and free the list entry after the RCU grace period elapses. Found by Linux Verification Center (linuxtesting.org). Fixes: 5d637d5aabd8 ("mac802154: add llsec structures and mutators") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin Acked-by: Alexander Aring Message-ID: <20240228163840.6667-1-pchelkin@ispras.ru> Signed-off-by: Stefan Schmidt Signed-off-by: Sasha Levin --- include/net/cfg802154.h | 1 + net/mac802154/llsec.c | 18 +++++++++++++----- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/include/net/cfg802154.h b/include/net/cfg802154.h index cd95711b12b8e..76d2cd2e2b309 100644 --- a/include/net/cfg802154.h +++ b/include/net/cfg802154.h @@ -401,6 +401,7 @@ struct ieee802154_llsec_key { struct ieee802154_llsec_key_entry { struct list_head list; + struct rcu_head rcu; struct ieee802154_llsec_key_id id; struct ieee802154_llsec_key *key; diff --git a/net/mac802154/llsec.c b/net/mac802154/llsec.c index 8d2eabc71bbeb..f13b07ebfb98a 100644 --- a/net/mac802154/llsec.c +++ b/net/mac802154/llsec.c @@ -265,19 +265,27 @@ int mac802154_llsec_key_add(struct mac802154_llsec *sec, return -ENOMEM; } +static void mac802154_llsec_key_del_rcu(struct rcu_head *rcu) +{ + struct ieee802154_llsec_key_entry *pos; + struct mac802154_llsec_key *mkey; + + pos = container_of(rcu, struct ieee802154_llsec_key_entry, rcu); + mkey = container_of(pos->key, struct mac802154_llsec_key, key); + + llsec_key_put(mkey); + kfree_sensitive(pos); +} + int mac802154_llsec_key_del(struct mac802154_llsec *sec, const struct ieee802154_llsec_key_id *key) { struct ieee802154_llsec_key_entry *pos; list_for_each_entry(pos, &sec->table.keys, list) { - struct mac802154_llsec_key *mkey; - - mkey = container_of(pos->key, struct mac802154_llsec_key, key); - if (llsec_key_id_equal(&pos->id, key)) { list_del_rcu(&pos->list); - llsec_key_put(mkey); + call_rcu(&pos->rcu, mac802154_llsec_key_del_rcu); return 0; } } -- 2.43.0