From 828fd2e892b03d05e9f573839e7b2d27835703bd Mon Sep 17 00:00:00 2001 From: Xin Long Date: Thu, 20 Aug 2020 15:34:47 +0800 Subject: tipc: call rcu_read_lock() in tipc_aead_encrypt_done() [ Upstream commit f6db9096416209474090d64d8284e7c16c3d8873 ] b->media->send_msg() requires rcu_read_lock(), as we can see elsewhere in tipc, tipc_bearer_xmit, tipc_bearer_xmit_skb and tipc_bearer_bc_xmit(). Syzbot has reported this issue as: net/tipc/bearer.c:466 suspicious rcu_dereference_check() usage! Workqueue: cryptd cryptd_queue_worker Call Trace: tipc_l2_send_msg+0x354/0x420 net/tipc/bearer.c:466 tipc_aead_encrypt_done+0x204/0x3a0 net/tipc/crypto.c:761 cryptd_aead_crypt+0xe8/0x1d0 crypto/cryptd.c:739 cryptd_queue_worker+0x118/0x1b0 crypto/cryptd.c:181 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 So fix it by calling rcu_read_lock() in tipc_aead_encrypt_done() for b->media->send_msg(). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Reported-by: syzbot+47bbc6b678d317cccbe0@syzkaller.appspotmail.com Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/crypto.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/tipc') diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c index c8c47fc72653..d6426b6cc9c5 100644 --- a/net/tipc/crypto.c +++ b/net/tipc/crypto.c @@ -757,10 +757,12 @@ static void tipc_aead_encrypt_done(struct crypto_async_request *base, int err) switch (err) { case 0: this_cpu_inc(tx->stats->stat[STAT_ASYNC_OK]); + rcu_read_lock(); if (likely(test_bit(0, &b->up))) b->media->send_msg(net, skb, b, &tx_ctx->dst); else kfree_skb(skb); + rcu_read_unlock(); break; case -EINPROGRESS: return; -- cgit v1.2.3 From 3942262b7499405223dcc219bc58cc540eb7651b Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Sat, 15 Aug 2020 16:29:15 -0700 Subject: tipc: fix uninit skb->data in tipc_nl_compat_dumpit() [ Upstream commit 47733f9daf4fe4f7e0eb9e273f21ad3a19130487 ] __tipc_nl_compat_dumpit() has two callers, and it expects them to pass a valid nlmsghdr via arg->data. This header is artificial and crafted just for __tipc_nl_compat_dumpit(). tipc_nl_compat_publ_dump() does so by putting a genlmsghdr as well as some nested attribute, TIPC_NLA_SOCK. But the other caller tipc_nl_compat_dumpit() does not, this leaves arg->data uninitialized on this call path. Fix this by just adding a similar nlmsghdr without any payload in tipc_nl_compat_dumpit(). This bug exists since day 1, but the recent commit 6ea67769ff33 ("net: tipc: prepare attrs in __tipc_nl_compat_dumpit()") makes it easier to appear. Reported-and-tested-by: syzbot+0e7181deafa7e0b79923@syzkaller.appspotmail.com Fixes: d0796d1ef63d ("tipc: convert legacy nl bearer dump to nl compat") Cc: Jon Maloy Cc: Ying Xue Cc: Richard Alpe Signed-off-by: Cong Wang Acked-by: Ying Xue Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/netlink_compat.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 217516357ef2..90e3c70a91ad 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -275,8 +275,9 @@ err_out: static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, struct tipc_nl_compat_msg *msg) { - int err; + struct nlmsghdr *nlh; struct sk_buff *arg; + int err; if (msg->req_type && (!msg->req_size || !TLV_CHECK_TYPE(msg->req, msg->req_type))) @@ -305,6 +306,15 @@ static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, return -ENOMEM; } + nlh = nlmsg_put(arg, 0, 0, tipc_genl_family.id, 0, NLM_F_MULTI); + if (!nlh) { + kfree_skb(arg); + kfree_skb(msg->rep); + msg->rep = NULL; + return -EMSGSIZE; + } + nlmsg_end(arg, nlh); + err = __tipc_nl_compat_dumpit(cmd, msg, arg); if (err) { kfree_skb(msg->rep); -- cgit v1.2.3