[PATCH AUTOSEL 5.3 01/33] net: ipv6: fix listify ip6_rcv_finish in case of forwarding

[PATCH AUTOSEL 5.3 01/33] net: ipv6: fix listify ip6_rcv_finish in case of forwarding

[Sasha Levin]

From: Xin Long <lucien.xin@gmail.com>

[ Upstream commit c7a42eb49212f93a800560662d17d5293960d3c3 ]

We need a similar fix for ipv6 as Commit 0761680d5215 ("net: ipv4: fix
listify ip_rcv_finish in case of forwarding") does for ipv4.

This issue can be reprocuded by syzbot since Commit 323ebb61e32b ("net:
use listified RX for handling GRO_NORMAL skbs") on net-next. The call
trace was:

  kernel BUG at include/linux/skbuff.h:2225!
  RIP: 0010:__skb_pull include/linux/skbuff.h:2225 [inline]
  RIP: 0010:skb_pull+0xea/0x110 net/core/skbuff.c:1902
  Call Trace:
    sctp_inq_pop+0x2f1/0xd80 net/sctp/inqueue.c:202
    sctp_endpoint_bh_rcv+0x184/0x8d0 net/sctp/endpointola.c:385
    sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80
    sctp_rcv+0x2807/0x3590 net/sctp/input.c:256
    sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049
    ip6_protocol_deliver_rcu+0x2fe/0x1660 net/ipv6/ip6_input.c:397
    ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438
    NF_HOOK include/linux/netfilter.h:305 [inline]
    NF_HOOK include/linux/netfilter.h:299 [inline]
    ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447
    dst_input include/net/dst.h:442 [inline]
    ip6_sublist_rcv_finish+0x98/0x1e0 net/ipv6/ip6_input.c:84
    ip6_list_rcv_finish net/ipv6/ip6_input.c:118 [inline]
    ip6_sublist_rcv+0x80c/0xcf0 net/ipv6/ip6_input.c:282
    ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:316
    __netif_receive_skb_list_ptype net/core/dev.c:5049 [inline]
    __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5097
    __netif_receive_skb_list net/core/dev.c:5149 [inline]
    netif_receive_skb_list_internal+0x7eb/0xe60 net/core/dev.c:5244
    gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5757
    gro_normal_list net/core/dev.c:5755 [inline]
    gro_normal_one net/core/dev.c:5769 [inline]
    napi_frags_finish net/core/dev.c:5782 [inline]
    napi_gro_frags+0xa6a/0xea0 net/core/dev.c:5855
    tun_get_user+0x2e98/0x3fa0 drivers/net/tun.c:1974
    tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2020

Fixes: d8269e2cbf90 ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()")
Fixes: 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs")
Reported-by: syzbot+eb349eeee854e389c36d@syzkaller.appspotmail.com
Reported-by: syzbot+4a0643a653ac375612d1@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv6/ip6_input.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index a593aaf257483..2bb0b66181a74 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -80,8 +80,10 @@ static void ip6_sublist_rcv_finish(struct list_head *head)
 {
 	struct sk_buff *skb, *next;
 
-	list_for_each_entry_safe(skb, next, head, list)
+	list_for_each_entry_safe(skb, next, head, list) {
+		skb_list_del_init(skb);
 		dst_input(skb);
+	}
 }
 
 static void ip6_list_rcv_finish(struct net *net, struct sock *sk,
-- 
2.20.1

[PATCH AUTOSEL 5.3 02/33] sch_netem: fix rcu splat in netem_enqueue()

[Sasha Levin]

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 159d2c7d8106177bd9a986fd005a311fe0d11285 ]

qdisc_root() use from netem_enqueue() triggers a lockdep warning.

__dev_queue_xmit() uses rcu_read_lock_bh() which is
not equivalent to rcu_read_lock() + local_bh_disable_bh as far
as lockdep is concerned.

WARNING: suspicious RCU usage
5.3.0-rc7+ #0 Not tainted
-----------------------------
include/net/sch_generic.h:492 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz-executor427/8855:
 #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline]
 #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x2dc/0x2570 net/ipv4/ip_output.c:214
 #1: 00000000b5525c01 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x3650 net/core/dev.c:3804
 #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: spin_lock include/linux/spinlock.h:338 [inline]
 #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_xmit_skb net/core/dev.c:3502 [inline]
 #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_queue_xmit+0x14b8/0x3650 net/core/dev.c:3838

stack backtrace:
CPU: 0 PID: 8855 Comm: syz-executor427 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5357
 qdisc_root include/net/sch_generic.h:492 [inline]
 netem_enqueue+0x1cfb/0x2d80 net/sched/sch_netem.c:479
 __dev_xmit_skb net/core/dev.c:3527 [inline]
 __dev_queue_xmit+0x15d2/0x3650 net/core/dev.c:3838
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
 neigh_hh_output include/net/neighbour.h:500 [inline]
 neigh_output include/net/neighbour.h:509 [inline]
 ip_finish_output2+0x1726/0x2570 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x5fc/0xb90 net/ipv4/ip_output.c:290
 ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip_mc_output+0x292/0xf40 net/ipv4/ip_output.c:417
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:125
 ip_send_skb+0x42/0xf0 net/ipv4/ip_output.c:1555
 udp_send_skb.isra.0+0x6b2/0x1160 net/ipv4/udp.c:887
 udp_sendmsg+0x1e96/0x2820 net/ipv4/udp.c:1174
 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2311
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg net/socket.c:2439 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/sch_generic.h | 5 +++++
 net/sched/sch_netem.c     | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 6b6b01234dd9d..58b1fbc884a7a 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -520,6 +520,11 @@ static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
 	return q;
 }
 
+static inline struct Qdisc *qdisc_root_bh(const struct Qdisc *qdisc)
+{
+	return rcu_dereference_bh(qdisc->dev_queue->qdisc);
+}
+
 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
 {
 	return qdisc->dev_queue->qdisc_sleeping;
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index f5cb35e550f8d..0e44039e729c7 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -476,7 +476,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 	 * skb will be queued.
 	 */
 	if (count > 1 && (skb2 = skb_clone(skb, GFP_ATOMIC)) != NULL) {
-		struct Qdisc *rootq = qdisc_root(sch);
+		struct Qdisc *rootq = qdisc_root_bh(sch);
 		u32 dupsave = q->duplicate; /* prevent duplicating a dup... */
 
 		q->duplicate = 0;
-- 
2.20.1

[PATCH AUTOSEL 5.3 03/33] net: sched: sch_sfb: don't call qdisc_put() while holding tree lock

[Sasha Levin]

From: Vlad Buslov <vladbu@mellanox.com>

[ Upstream commit e3ae1f96accd21405715fe9c56b4d83bc7d96d44 ]

Recent changes that removed rtnl dependency from rules update path of tc
also made tcf_block_put() function sleeping. This function is called from
ops->destroy() of several Qdisc implementations, which in turn is called by
qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock,
which results sleeping-while-atomic BUG.

Steps to reproduce for sfb:

tc qdisc add dev ens1f0 handle 1: root sfb
tc qdisc add dev ens1f0 parent 1:10 handle 50: sfq perturb 10
tc qdisc change dev ens1f0 root handle 1: sfb

Resulting dmesg:

[ 7265.938717] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909
[ 7265.940152] in_atomic(): 1, irqs_disabled(): 0, pid: 28579, name: tc
[ 7265.941455] INFO: lockdep is turned off.
[ 7265.942744] CPU: 11 PID: 28579 Comm: tc Tainted: G        W         5.3.0-rc8+ #721
[ 7265.944065] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 7265.945396] Call Trace:
[ 7265.946709]  dump_stack+0x85/0xc0
[ 7265.947994]  ___might_sleep.cold+0xac/0xbc
[ 7265.949282]  __mutex_lock+0x5b/0x960
[ 7265.950543]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 7265.951803]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 7265.953022]  tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 7265.954248]  tcf_block_put_ext.part.0+0x21/0x50
[ 7265.955478]  tcf_block_put+0x50/0x70
[ 7265.956694]  sfq_destroy+0x15/0x50 [sch_sfq]
[ 7265.957898]  qdisc_destroy+0x5f/0x160
[ 7265.959099]  sfb_change+0x175/0x330 [sch_sfb]
[ 7265.960304]  tc_modify_qdisc+0x324/0x840
[ 7265.961503]  rtnetlink_rcv_msg+0x170/0x4b0
[ 7265.962692]  ? netlink_deliver_tap+0x95/0x400
[ 7265.963876]  ? rtnl_dellink+0x2d0/0x2d0
[ 7265.965064]  netlink_rcv_skb+0x49/0x110
[ 7265.966251]  netlink_unicast+0x171/0x200
[ 7265.967427]  netlink_sendmsg+0x224/0x3f0
[ 7265.968595]  sock_sendmsg+0x5e/0x60
[ 7265.969753]  ___sys_sendmsg+0x2ae/0x330
[ 7265.970916]  ? ___sys_recvmsg+0x159/0x1f0
[ 7265.972074]  ? do_wp_page+0x9c/0x790
[ 7265.973233]  ? __handle_mm_fault+0xcd3/0x19e0
[ 7265.974407]  __sys_sendmsg+0x59/0xa0
[ 7265.975591]  do_syscall_64+0x5c/0xb0
[ 7265.976753]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 7265.977938] RIP: 0033:0x7f229069f7b8
[ 7265.979117] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5
4
[ 7265.981681] RSP: 002b:00007ffd7ed2d158 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 7265.983001] RAX: ffffffffffffffda RBX: 000000005d813ca1 RCX: 00007f229069f7b8
[ 7265.984336] RDX: 0000000000000000 RSI: 00007ffd7ed2d1c0 RDI: 0000000000000003
[ 7265.985682] RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000165c9a0
[ 7265.987021] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001
[ 7265.988309] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000

In sfb_change() function use qdisc_purge_queue() instead of
qdisc_tree_flush_backlog() to properly reset old child Qdisc and save
pointer to it into local temporary variable. Put reference to Qdisc after
sch tree lock is released in order not to call potentially sleeping cls API
in atomic section. This is safe to do because Qdisc has already been reset
by qdisc_purge_queue() inside sch tree lock critical section.

Reported-by: syzbot+ac54455281db908c581e@syzkaller.appspotmail.com
Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex")
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sched/sch_sfb.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/sched/sch_sfb.c b/net/sched/sch_sfb.c
index 1dff8506a7155..d448fe3068e5b 100644
--- a/net/sched/sch_sfb.c
+++ b/net/sched/sch_sfb.c
@@ -488,7 +488,7 @@ static int sfb_change(struct Qdisc *sch, struct nlattr *opt,
 		      struct netlink_ext_ack *extack)
 {
 	struct sfb_sched_data *q = qdisc_priv(sch);
-	struct Qdisc *child;
+	struct Qdisc *child, *old;
 	struct nlattr *tb[TCA_SFB_MAX + 1];
 	const struct tc_sfb_qopt *ctl = &sfb_default_ops;
 	u32 limit;
@@ -518,8 +518,8 @@ static int sfb_change(struct Qdisc *sch, struct nlattr *opt,
 		qdisc_hash_add(child, true);
 	sch_tree_lock(sch);
 
-	qdisc_tree_flush_backlog(q->qdisc);
-	qdisc_put(q->qdisc);
+	qdisc_purge_queue(q->qdisc);
+	old = q->qdisc;
 	q->qdisc = child;
 
 	q->rehash_interval = msecs_to_jiffies(ctl->rehash_interval);
@@ -542,6 +542,7 @@ static int sfb_change(struct Qdisc *sch, struct nlattr *opt,
 	sfb_init_perturbation(1, q);
 
 	sch_tree_unlock(sch);
+	qdisc_put(old);
 
 	return 0;
 }
-- 
2.20.1

[PATCH AUTOSEL 5.3 04/33] rxrpc: Fix call ref leak

[Sasha Levin]

From: David Howells <dhowells@redhat.com>

[ Upstream commit c48fc11b69e95007109206311b0187a3090591f3 ]

When sendmsg() finds a call to continue on with, if the call is in an
inappropriate state, it doesn't release the ref it just got on that call
before returning an error.

This causes the following symptom to show up with kasan:

	BUG: KASAN: use-after-free in rxrpc_send_keepalive+0x8a2/0x940
	net/rxrpc/output.c:635
	Read of size 8 at addr ffff888064219698 by task kworker/0:3/11077

where line 635 is:

	whdr.epoch	= htonl(peer->local->rxnet->epoch);

The local endpoint (which cannot be pinned by the call) has been released,
but not the peer (which is pinned by the call).

Fix this by releasing the call in the error path.

Fixes: 37411cad633f ("rxrpc: Fix potential NULL-pointer exception")
Reported-by: syzbot+d850c266e3df14da1d31@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rxrpc/sendmsg.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 6a1547b270fef..22f51a7e356ee 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -661,6 +661,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 		case RXRPC_CALL_SERVER_PREALLOC:
 		case RXRPC_CALL_SERVER_SECURING:
 		case RXRPC_CALL_SERVER_ACCEPTING:
+			rxrpc_put_call(call, rxrpc_call_put);
 			ret = -EBUSY;
 			goto error_release_sock;
 		default:
-- 
2.20.1

[PATCH AUTOSEL 5.3 05/33] rxrpc: Fix trace-after-put looking at the put peer record

[Sasha Levin]

From: David Howells <dhowells@redhat.com>

[ Upstream commit 55f6c98e3674ce16038a1949c3f9ca5a9a99f289 ]

rxrpc_put_peer() calls trace_rxrpc_peer() after it has done the decrement
of the refcount - which looks at the debug_id in the peer record.  But
unless the refcount was reduced to zero, we no longer have the right to
look in the record and, indeed, it may be deleted by some other thread.

Fix this by getting the debug_id out before decrementing the refcount and
then passing that into the tracepoint.

This can cause the following symptoms:

    BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411
    [inline]
    BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0
    net/rxrpc/peer_object.c:435
    Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216

Fixes: 1159d4b496f5 ("rxrpc: Add a tracepoint to track rxrpc_peer refcounting")
Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/trace/events/rxrpc.h |  6 +++---
 net/rxrpc/peer_object.c      | 11 +++++++----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index edc5c887a44c8..45556fe771c36 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -519,10 +519,10 @@ TRACE_EVENT(rxrpc_local,
 	    );
 
 TRACE_EVENT(rxrpc_peer,
-	    TP_PROTO(struct rxrpc_peer *peer, enum rxrpc_peer_trace op,
+	    TP_PROTO(unsigned int peer_debug_id, enum rxrpc_peer_trace op,
 		     int usage, const void *where),
 
-	    TP_ARGS(peer, op, usage, where),
+	    TP_ARGS(peer_debug_id, op, usage, where),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,	peer		)
@@ -532,7 +532,7 @@ TRACE_EVENT(rxrpc_peer,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->peer = peer->debug_id;
+		    __entry->peer = peer_debug_id;
 		    __entry->op = op;
 		    __entry->usage = usage;
 		    __entry->where = where;
diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c
index 9c3ac96f71cbf..b700b7ecaa3d8 100644
--- a/net/rxrpc/peer_object.c
+++ b/net/rxrpc/peer_object.c
@@ -382,7 +382,7 @@ struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer)
 	int n;
 
 	n = atomic_inc_return(&peer->usage);
-	trace_rxrpc_peer(peer, rxrpc_peer_got, n, here);
+	trace_rxrpc_peer(peer->debug_id, rxrpc_peer_got, n, here);
 	return peer;
 }
 
@@ -396,7 +396,7 @@ struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer)
 	if (peer) {
 		int n = atomic_fetch_add_unless(&peer->usage, 1, 0);
 		if (n > 0)
-			trace_rxrpc_peer(peer, rxrpc_peer_got, n + 1, here);
+			trace_rxrpc_peer(peer->debug_id, rxrpc_peer_got, n + 1, here);
 		else
 			peer = NULL;
 	}
@@ -426,11 +426,13 @@ static void __rxrpc_put_peer(struct rxrpc_peer *peer)
 void rxrpc_put_peer(struct rxrpc_peer *peer)
 {
 	const void *here = __builtin_return_address(0);
+	unsigned int debug_id;
 	int n;
 
 	if (peer) {
+		debug_id = peer->debug_id;
 		n = atomic_dec_return(&peer->usage);
-		trace_rxrpc_peer(peer, rxrpc_peer_put, n, here);
+		trace_rxrpc_peer(debug_id, rxrpc_peer_put, n, here);
 		if (n == 0)
 			__rxrpc_put_peer(peer);
 	}
@@ -443,10 +445,11 @@ void rxrpc_put_peer(struct rxrpc_peer *peer)
 void rxrpc_put_peer_locked(struct rxrpc_peer *peer)
 {
 	const void *here = __builtin_return_address(0);
+	unsigned int debug_id = peer->debug_id;
 	int n;
 
 	n = atomic_dec_return(&peer->usage);
-	trace_rxrpc_peer(peer, rxrpc_peer_put, n, here);
+	trace_rxrpc_peer(debug_id, rxrpc_peer_put, n, here);
 	if (n == 0) {
 		hash_del_rcu(&peer->hash_link);
 		list_del_init(&peer->keepalive_link);
-- 
2.20.1

[PATCH AUTOSEL 5.3 06/33] rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record

[Sasha Levin]

From: David Howells <dhowells@redhat.com>

[ Upstream commit 9ebeddef58c41bd700419cdcece24cf64ce32276 ]

The rxrpc_peer record needs to hold a reference on the rxrpc_local record
it points as the peer is used as a base to access information in the
rxrpc_local record.

This can cause problems in __rxrpc_put_peer(), where we need the network
namespace pointer, and in rxrpc_send_keepalive(), where we need to access
the UDP socket, leading to symptoms like:

    BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411
    [inline]
    BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0
    net/rxrpc/peer_object.c:435
    Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216

Fix this by taking a ref on the local record for the peer record.

Fixes: ace45bec6d77 ("rxrpc: Fix firewall route keepalive")
Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing")
Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rxrpc/peer_object.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c
index b700b7ecaa3d8..64830d8c1fdb5 100644
--- a/net/rxrpc/peer_object.c
+++ b/net/rxrpc/peer_object.c
@@ -216,7 +216,7 @@ struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp)
 	peer = kzalloc(sizeof(struct rxrpc_peer), gfp);
 	if (peer) {
 		atomic_set(&peer->usage, 1);
-		peer->local = local;
+		peer->local = rxrpc_get_local(local);
 		INIT_HLIST_HEAD(&peer->error_targets);
 		peer->service_conns = RB_ROOT;
 		seqlock_init(&peer->service_conn_lock);
@@ -307,7 +307,6 @@ void rxrpc_new_incoming_peer(struct rxrpc_sock *rx, struct rxrpc_local *local,
 	unsigned long hash_key;
 
 	hash_key = rxrpc_peer_hash_key(local, &peer->srx);
-	peer->local = local;
 	rxrpc_init_peer(rx, peer, hash_key);
 
 	spin_lock(&rxnet->peer_hash_lock);
@@ -417,6 +416,7 @@ static void __rxrpc_put_peer(struct rxrpc_peer *peer)
 	list_del_init(&peer->keepalive_link);
 	spin_unlock_bh(&rxnet->peer_hash_lock);
 
+	rxrpc_put_local(peer->local);
 	kfree_rcu(peer, rcu);
 }
 
@@ -453,6 +453,7 @@ void rxrpc_put_peer_locked(struct rxrpc_peer *peer)
 	if (n == 0) {
 		hash_del_rcu(&peer->hash_link);
 		list_del_init(&peer->keepalive_link);
+		rxrpc_put_local(peer->local);
 		kfree_rcu(peer, rcu);
 	}
 }
-- 
2.20.1

[PATCH AUTOSEL 5.3 07/33] llc: fix sk_buff leak in llc_sap_state_process()

[Sasha Levin]

From: Eric Biggers <ebiggers@google.com>

[ Upstream commit c6ee11c39fcc1fb55130748990a8f199e76263b4 ]

syzbot reported:

    BUG: memory leak
    unreferenced object 0xffff888116270800 (size 224):
       comm "syz-executor641", pid 7047, jiffies 4294947360 (age 13.860s)
       hex dump (first 32 bytes):
         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
         00 20 e1 2a 81 88 ff ff 00 40 3d 2a 81 88 ff ff  . .*.....@=*....
       backtrace:
         [<000000004d41b4cc>] kmemleak_alloc_recursive  include/linux/kmemleak.h:55 [inline]
         [<000000004d41b4cc>] slab_post_alloc_hook mm/slab.h:439 [inline]
         [<000000004d41b4cc>] slab_alloc_node mm/slab.c:3269 [inline]
         [<000000004d41b4cc>] kmem_cache_alloc_node+0x153/0x2a0 mm/slab.c:3579
         [<00000000506a5965>] __alloc_skb+0x6e/0x210 net/core/skbuff.c:198
         [<000000001ba5a161>] alloc_skb include/linux/skbuff.h:1058 [inline]
         [<000000001ba5a161>] alloc_skb_with_frags+0x5f/0x250  net/core/skbuff.c:5327
         [<0000000047d9c78b>] sock_alloc_send_pskb+0x269/0x2a0  net/core/sock.c:2225
         [<000000003828fe54>] sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2242
         [<00000000e34d94f9>] llc_ui_sendmsg+0x10a/0x540 net/llc/af_llc.c:933
         [<00000000de2de3fb>] sock_sendmsg_nosec net/socket.c:652 [inline]
         [<00000000de2de3fb>] sock_sendmsg+0x54/0x70 net/socket.c:671
         [<000000008fe16e7a>] __sys_sendto+0x148/0x1f0 net/socket.c:1964
	 [...]

The bug is that llc_sap_state_process() always takes an extra reference
to the skb, but sometimes neither llc_sap_next_state() nor
llc_sap_state_process() itself drops this reference.

Fix it by changing llc_sap_next_state() to never consume a reference to
the skb, rather than sometimes do so and sometimes not.  Then remove the
extra skb_get() and kfree_skb() from llc_sap_state_process().

Reported-by: syzbot+6bf095f9becf5efef645@syzkaller.appspotmail.com
Reported-by: syzbot+31c16aa4202dace3812e@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/llc/llc_s_ac.c | 12 +++++++++---
 net/llc/llc_sap.c  | 23 ++++++++---------------
 2 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/net/llc/llc_s_ac.c b/net/llc/llc_s_ac.c
index a94bd56bcac6f..7ae4cc684d3ab 100644
--- a/net/llc/llc_s_ac.c
+++ b/net/llc/llc_s_ac.c
@@ -58,8 +58,10 @@ int llc_sap_action_send_ui(struct llc_sap *sap, struct sk_buff *skb)
 			    ev->daddr.lsap, LLC_PDU_CMD);
 	llc_pdu_init_as_ui_cmd(skb);
 	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);
-	if (likely(!rc))
+	if (likely(!rc)) {
+		skb_get(skb);
 		rc = dev_queue_xmit(skb);
+	}
 	return rc;
 }
 
@@ -81,8 +83,10 @@ int llc_sap_action_send_xid_c(struct llc_sap *sap, struct sk_buff *skb)
 			    ev->daddr.lsap, LLC_PDU_CMD);
 	llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, 0);
 	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);
-	if (likely(!rc))
+	if (likely(!rc)) {
+		skb_get(skb);
 		rc = dev_queue_xmit(skb);
+	}
 	return rc;
 }
 
@@ -135,8 +139,10 @@ int llc_sap_action_send_test_c(struct llc_sap *sap, struct sk_buff *skb)
 			    ev->daddr.lsap, LLC_PDU_CMD);
 	llc_pdu_init_as_test_cmd(skb);
 	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);
-	if (likely(!rc))
+	if (likely(!rc)) {
+		skb_get(skb);
 		rc = dev_queue_xmit(skb);
+	}
 	return rc;
 }
 
diff --git a/net/llc/llc_sap.c b/net/llc/llc_sap.c
index a7f7b8ff47292..be419062e19a6 100644
--- a/net/llc/llc_sap.c
+++ b/net/llc/llc_sap.c
@@ -197,29 +197,22 @@ static int llc_sap_next_state(struct llc_sap *sap, struct sk_buff *skb)
  *	After executing actions of the event, upper layer will be indicated
  *	if needed(on receiving an UI frame). sk can be null for the
  *	datalink_proto case.
+ *
+ *	This function always consumes a reference to the skb.
  */
 static void llc_sap_state_process(struct llc_sap *sap, struct sk_buff *skb)
 {
 	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
 
-	/*
-	 * We have to hold the skb, because llc_sap_next_state
-	 * will kfree it in the sending path and we need to
-	 * look at the skb->cb, where we encode llc_sap_state_ev.
-	 */
-	skb_get(skb);
 	ev->ind_cfm_flag = 0;
 	llc_sap_next_state(sap, skb);
-	if (ev->ind_cfm_flag == LLC_IND) {
-		if (skb->sk->sk_state == TCP_LISTEN)
-			kfree_skb(skb);
-		else {
-			llc_save_primitive(skb->sk, skb, ev->prim);
 
-			/* queue skb to the user. */
-			if (sock_queue_rcv_skb(skb->sk, skb))
-				kfree_skb(skb);
-		}
+	if (ev->ind_cfm_flag == LLC_IND && skb->sk->sk_state != TCP_LISTEN) {
+		llc_save_primitive(skb->sk, skb, ev->prim);
+
+		/* queue skb to the user. */
+		if (sock_queue_rcv_skb(skb->sk, skb) == 0)
+			return;
 	}
 	kfree_skb(skb);
 }
-- 
2.20.1

[PATCH AUTOSEL 5.3 08/33] llc: fix sk_buff leak in llc_conn_service()

[Sasha Levin]

From: Eric Biggers <ebiggers@google.com>

[ Upstream commit b74555de21acd791f12c4a1aeaf653dd7ac21133 ]

syzbot reported:

    BUG: memory leak
    unreferenced object 0xffff88811eb3de00 (size 224):
       comm "syz-executor559", pid 7315, jiffies 4294943019 (age 10.300s)
       hex dump (first 32 bytes):
         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
         00 a0 38 24 81 88 ff ff 00 c0 f2 15 81 88 ff ff  ..8$............
       backtrace:
         [<000000008d1c66a1>] kmemleak_alloc_recursive  include/linux/kmemleak.h:55 [inline]
         [<000000008d1c66a1>] slab_post_alloc_hook mm/slab.h:439 [inline]
         [<000000008d1c66a1>] slab_alloc_node mm/slab.c:3269 [inline]
         [<000000008d1c66a1>] kmem_cache_alloc_node+0x153/0x2a0 mm/slab.c:3579
         [<00000000447d9496>] __alloc_skb+0x6e/0x210 net/core/skbuff.c:198
         [<000000000cdbf82f>] alloc_skb include/linux/skbuff.h:1058 [inline]
         [<000000000cdbf82f>] llc_alloc_frame+0x66/0x110 net/llc/llc_sap.c:54
         [<000000002418b52e>] llc_conn_ac_send_sabme_cmd_p_set_x+0x2f/0x140  net/llc/llc_c_ac.c:777
         [<000000001372ae17>] llc_exec_conn_trans_actions net/llc/llc_conn.c:475  [inline]
         [<000000001372ae17>] llc_conn_service net/llc/llc_conn.c:400 [inline]
         [<000000001372ae17>] llc_conn_state_process+0x1ac/0x640  net/llc/llc_conn.c:75
         [<00000000f27e53c1>] llc_establish_connection+0x110/0x170  net/llc/llc_if.c:109
         [<00000000291b2ca0>] llc_ui_connect+0x10e/0x370 net/llc/af_llc.c:477
         [<000000000f9c740b>] __sys_connect+0x11d/0x170 net/socket.c:1840
         [...]

The bug is that most callers of llc_conn_send_pdu() assume it consumes a
reference to the skb, when actually due to commit b85ab56c3f81 ("llc:
properly handle dev_queue_xmit() return value") it doesn't.

Revert most of that commit, and instead make the few places that need
llc_conn_send_pdu() to *not* consume a reference call skb_get() before.

Fixes: b85ab56c3f81 ("llc: properly handle dev_queue_xmit() return value")
Reported-by: syzbot+6b825a6494a04cc0e3f7@syzkaller.appspotmail.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/llc_conn.h |  2 +-
 net/llc/llc_c_ac.c     |  8 ++++++--
 net/llc/llc_conn.c     | 32 +++++++++-----------------------
 3 files changed, 16 insertions(+), 26 deletions(-)

diff --git a/include/net/llc_conn.h b/include/net/llc_conn.h
index df528a6235487..ea985aa7a6c5e 100644
--- a/include/net/llc_conn.h
+++ b/include/net/llc_conn.h
@@ -104,7 +104,7 @@ void llc_sk_reset(struct sock *sk);
 
 /* Access to a connection */
 int llc_conn_state_process(struct sock *sk, struct sk_buff *skb);
-int llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb);
+void llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb);
 void llc_conn_rtn_pdu(struct sock *sk, struct sk_buff *skb);
 void llc_conn_resend_i_pdu_as_cmd(struct sock *sk, u8 nr, u8 first_p_bit);
 void llc_conn_resend_i_pdu_as_rsp(struct sock *sk, u8 nr, u8 first_f_bit);
diff --git a/net/llc/llc_c_ac.c b/net/llc/llc_c_ac.c
index 4d78375f9872d..647c0554d04cd 100644
--- a/net/llc/llc_c_ac.c
+++ b/net/llc/llc_c_ac.c
@@ -372,6 +372,7 @@ int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
 	llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR);
 	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
 	if (likely(!rc)) {
+		skb_get(skb);
 		llc_conn_send_pdu(sk, skb);
 		llc_conn_ac_inc_vs_by_1(sk, skb);
 	}
@@ -389,7 +390,8 @@ static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb)
 	llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
 	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
 	if (likely(!rc)) {
-		rc = llc_conn_send_pdu(sk, skb);
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
 		llc_conn_ac_inc_vs_by_1(sk, skb);
 	}
 	return rc;
@@ -406,6 +408,7 @@ int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
 	llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
 	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
 	if (likely(!rc)) {
+		skb_get(skb);
 		llc_conn_send_pdu(sk, skb);
 		llc_conn_ac_inc_vs_by_1(sk, skb);
 	}
@@ -916,7 +919,8 @@ static int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk,
 	llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR);
 	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
 	if (likely(!rc)) {
-		rc = llc_conn_send_pdu(sk, skb);
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
 		llc_conn_ac_inc_vs_by_1(sk, skb);
 	}
 	return rc;
diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c
index 4ff89cb7c86f7..ed2aca12460ca 100644
--- a/net/llc/llc_conn.c
+++ b/net/llc/llc_conn.c
@@ -30,7 +30,7 @@
 #endif
 
 static int llc_find_offset(int state, int ev_type);
-static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *skb);
+static void llc_conn_send_pdus(struct sock *sk);
 static int llc_conn_service(struct sock *sk, struct sk_buff *skb);
 static int llc_exec_conn_trans_actions(struct sock *sk,
 				       struct llc_conn_state_trans *trans,
@@ -193,11 +193,11 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
 	return rc;
 }
 
-int llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb)
+void llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb)
 {
 	/* queue PDU to send to MAC layer */
 	skb_queue_tail(&sk->sk_write_queue, skb);
-	return llc_conn_send_pdus(sk, skb);
+	llc_conn_send_pdus(sk);
 }
 
 /**
@@ -255,7 +255,7 @@ void llc_conn_resend_i_pdu_as_cmd(struct sock *sk, u8 nr, u8 first_p_bit)
 	if (howmany_resend > 0)
 		llc->vS = (llc->vS + 1) % LLC_2_SEQ_NBR_MODULO;
 	/* any PDUs to re-send are queued up; start sending to MAC */
-	llc_conn_send_pdus(sk, NULL);
+	llc_conn_send_pdus(sk);
 out:;
 }
 
@@ -296,7 +296,7 @@ void llc_conn_resend_i_pdu_as_rsp(struct sock *sk, u8 nr, u8 first_f_bit)
 	if (howmany_resend > 0)
 		llc->vS = (llc->vS + 1) % LLC_2_SEQ_NBR_MODULO;
 	/* any PDUs to re-send are queued up; start sending to MAC */
-	llc_conn_send_pdus(sk, NULL);
+	llc_conn_send_pdus(sk);
 out:;
 }
 
@@ -340,16 +340,12 @@ int llc_conn_remove_acked_pdus(struct sock *sk, u8 nr, u16 *how_many_unacked)
 /**
  *	llc_conn_send_pdus - Sends queued PDUs
  *	@sk: active connection
- *	@hold_skb: the skb held by caller, or NULL if does not care
  *
- *	Sends queued pdus to MAC layer for transmission. When @hold_skb is
- *	NULL, always return 0. Otherwise, return 0 if @hold_skb is sent
- *	successfully, or 1 for failure.
+ *	Sends queued pdus to MAC layer for transmission.
  */
-static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *hold_skb)
+static void llc_conn_send_pdus(struct sock *sk)
 {
 	struct sk_buff *skb;
-	int ret = 0;
 
 	while ((skb = skb_dequeue(&sk->sk_write_queue)) != NULL) {
 		struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
@@ -361,20 +357,10 @@ static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *hold_skb)
 			skb_queue_tail(&llc_sk(sk)->pdu_unack_q, skb);
 			if (!skb2)
 				break;
-			dev_queue_xmit(skb2);
-		} else {
-			bool is_target = skb == hold_skb;
-			int rc;
-
-			if (is_target)
-				skb_get(skb);
-			rc = dev_queue_xmit(skb);
-			if (is_target)
-				ret = rc;
+			skb = skb2;
 		}
+		dev_queue_xmit(skb);
 	}
-
-	return ret;
 }
 
 /**
-- 
2.20.1

[PATCH AUTOSEL 5.3 09/33] NFC: pn533: fix use-after-free and memleaks

[Sasha Levin]

From: Johan Hovold <johan@kernel.org>

[ Upstream commit 6af3aa57a0984e061f61308fe181a9a12359fecc ]

The driver would fail to deregister and its class device and free
related resources on late probe errors.

Reported-by: syzbot+cb035c75c03dbe34b796@syzkaller.appspotmail.com
Fixes: 32ecc75ded72 ("NFC: pn533: change order operations in dev registation")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nfc/pn533/usb.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/nfc/pn533/usb.c b/drivers/nfc/pn533/usb.c
index c5289eaf17eef..e897e4d768ef7 100644
--- a/drivers/nfc/pn533/usb.c
+++ b/drivers/nfc/pn533/usb.c
@@ -547,18 +547,25 @@ static int pn533_usb_probe(struct usb_interface *interface,
 
 	rc = pn533_finalize_setup(priv);
 	if (rc)
-		goto error;
+		goto err_deregister;
 
 	usb_set_intfdata(interface, phy);
 
 	return 0;
 
+err_deregister:
+	pn533_unregister_device(phy->priv);
 error:
+	usb_kill_urb(phy->in_urb);
+	usb_kill_urb(phy->out_urb);
+	usb_kill_urb(phy->ack_urb);
+
 	usb_free_urb(phy->in_urb);
 	usb_free_urb(phy->out_urb);
 	usb_free_urb(phy->ack_urb);
 	usb_put_dev(phy->udev);
 	kfree(in_buf);
+	kfree(phy->ack_buffer);
 
 	return rc;
 }
-- 
2.20.1

[PATCH AUTOSEL 5.3 10/33] bonding: fix potential NULL deref in bond_update_slave_arr

[Sasha Levin]

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit a7137534b597b7c303203e6bc3ed87e87a273bb8 ]

syzbot got a NULL dereference in bond_update_slave_arr() [1],
happening after a failure to allocate bond->slave_arr

A workqueue (bond_slave_arr_handler) is supposed to retry
the allocation later, but if the slave is removed before
the workqueue had a chance to complete, bond->slave_arr
can still be NULL.

[1]

Failed to build slave-array.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
Modules linked in:
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bond_update_slave_arr.cold+0xc6/0x198 drivers/net/bonding/bond_main.c:4039
RSP: 0018:ffff88018fe33678 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000290b000
RDX: 0000000000000000 RSI: ffffffff82b63037 RDI: ffff88019745ea20
RBP: ffff88018fe33760 R08: ffff880170754280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88019745ea00 R14: 0000000000000000 R15: ffff88018fe338b0
FS:  00007febd837d700(0000) GS:ffff8801dad00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004540a0 CR3: 00000001c242e005 CR4: 00000000001626f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 [<ffffffff82b5b45e>] __bond_release_one+0x43e/0x500 drivers/net/bonding/bond_main.c:1923
 [<ffffffff82b5b966>] bond_release drivers/net/bonding/bond_main.c:2039 [inline]
 [<ffffffff82b5b966>] bond_do_ioctl+0x416/0x870 drivers/net/bonding/bond_main.c:3562
 [<ffffffff83ae25f4>] dev_ifsioc+0x6f4/0x940 net/core/dev_ioctl.c:328
 [<ffffffff83ae2e58>] dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:495
 [<ffffffff83995ffd>] sock_do_ioctl+0x1bd/0x300 net/socket.c:1088
 [<ffffffff83996a80>] sock_ioctl+0x300/0x5d0 net/socket.c:1196
 [<ffffffff81b124db>] vfs_ioctl fs/ioctl.c:47 [inline]
 [<ffffffff81b124db>] file_ioctl fs/ioctl.c:501 [inline]
 [<ffffffff81b124db>] do_vfs_ioctl+0xacb/0x1300 fs/ioctl.c:688
 [<ffffffff81b12dc6>] SYSC_ioctl fs/ioctl.c:705 [inline]
 [<ffffffff81b12dc6>] SyS_ioctl+0xb6/0xe0 fs/ioctl.c:696
 [<ffffffff8101ccc8>] do_syscall_64+0x528/0x770 arch/x86/entry/common.c:305
 [<ffffffff84400091>] entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: ee6377147409 ("bonding: Simplify the xmit function for modes that use xmit_hash")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/bonding/bond_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 931d9d9356869..21d8fcc83c9ce 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4039,7 +4039,7 @@ int bond_update_slave_arr(struct bonding *bond, struct slave *skipslave)
 		 * this to-be-skipped slave to send a packet out.
 		 */
 		old_arr = rtnl_dereference(bond->slave_arr);
-		for (idx = 0; idx < old_arr->count; idx++) {
+		for (idx = 0; old_arr != NULL && idx < old_arr->count; idx++) {
 			if (skipslave == old_arr->arr[idx]) {
 				old_arr->arr[idx] =
 				    old_arr->arr[old_arr->count-1];
-- 
2.20.1

[PATCH AUTOSEL 5.3 11/33] netfilter: conntrack: avoid possible false sharing

[Sasha Levin]

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit e37542ba111f3974dc622ae0a21c1787318de500 ]

As hinted by KCSAN, we need at least one READ_ONCE()
to prevent a compiler optimization.

More details on :
https://github.com/google/ktsan/wiki/READ_ONCE-and-WRITE_ONCE#it-may-improve-performance

sysbot report :
BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct

read to 0xffff888123eb4f08 of 4 bytes by interrupt on cpu 0:
 __nf_ct_refresh_acct+0xd4/0x1b0 net/netfilter/nf_conntrack_core.c:1796
 nf_ct_refresh_acct include/net/netfilter/nf_conntrack.h:201 [inline]
 nf_conntrack_tcp_packet+0xd40/0x3390 net/netfilter/nf_conntrack_proto_tcp.c:1161
 nf_conntrack_handle_packet net/netfilter/nf_conntrack_core.c:1633 [inline]
 nf_conntrack_in+0x410/0xaa0 net/netfilter/nf_conntrack_core.c:1727
 ipv4_conntrack_in+0x27/0x40 net/netfilter/nf_conntrack_proto.c:178
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ip_rcv+0x12f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418
 __do_softirq+0x115/0x33f kernel/softirq.c:292

write to 0xffff888123eb4f08 of 4 bytes by task 7191 on cpu 1:
 __nf_ct_refresh_acct+0xfb/0x1b0 net/netfilter/nf_conntrack_core.c:1797
 nf_ct_refresh_acct include/net/netfilter/nf_conntrack.h:201 [inline]
 nf_conntrack_tcp_packet+0xd40/0x3390 net/netfilter/nf_conntrack_proto_tcp.c:1161
 nf_conntrack_handle_packet net/netfilter/nf_conntrack_core.c:1633 [inline]
 nf_conntrack_in+0x410/0xaa0 net/netfilter/nf_conntrack_core.c:1727
 ipv4_conntrack_local+0xbe/0x130 net/netfilter/nf_conntrack_proto.c:200
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 __ip_local_out+0x1f7/0x2b0 net/ipv4/ip_output.c:114
 ip_local_out+0x31/0x90 net/ipv4/ip_output.c:123
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:236
 __tcp_transmit_skb+0xdeb/0x1cd0 net/ipv4/tcp_output.c:1158
 __tcp_send_ack+0x246/0x300 net/ipv4/tcp_output.c:3685
 tcp_send_ack+0x34/0x40 net/ipv4/tcp_output.c:3691
 tcp_cleanup_rbuf+0x130/0x360 net/ipv4/tcp.c:1575

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7191 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: cc16921351d8 ("netfilter: conntrack: avoid same-timeout update")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Florian Westphal <fw@strlen.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nf_conntrack_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 81a8ef42b88d3..56b1cf82ed3aa 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1793,8 +1793,8 @@ void __nf_ct_refresh_acct(struct nf_conn *ct,
 	if (nf_ct_is_confirmed(ct))
 		extra_jiffies += nfct_time_stamp;
 
-	if (ct->timeout != extra_jiffies)
-		ct->timeout = extra_jiffies;
+	if (READ_ONCE(ct->timeout) != extra_jiffies)
+		WRITE_ONCE(ct->timeout, extra_jiffies);
 acct:
 	if (do_acct)
 		nf_ct_acct_update(ct, ctinfo, skb->len);
-- 
2.20.1

[PATCH AUTOSEL 5.3 12/33] blackhole_netdev: fix syzkaller reported issue

[Sasha Levin]

From: Mahesh Bandewar <maheshb@google.com>

[ Upstream commit b0818f80c8c1bc215bba276bd61c216014fab23b ]

While invalidating the dst, we assign backhole_netdev instead of
loopback device. However, this device does not have idev pointer
and hence no ip6_ptr even if IPv6 is enabled. Possibly this has
triggered the syzbot reported crash.

The syzbot report does not have reproducer, however, this is the
only device that doesn't have matching idev created.

Crash instruction is :

static inline bool ip6_ignore_linkdown(const struct net_device *dev)
{
        const struct inet6_dev *idev = __in6_dev_get(dev);

        return !!idev->cnf.ignore_routes_with_linkdown; <= crash
}

Also ipv6 always assumes presence of idev and never checks for it
being NULL (as does the above referenced code). So adding a idev
for the blackhole_netdev to avoid this class of crashes in the future.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv6/addrconf.c |  7 ++++++-
 net/ipv6/route.c    | 15 ++++++---------
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 34ccef18b40e6..4c87594d1389d 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -6996,7 +6996,7 @@ static struct rtnl_af_ops inet6_ops __read_mostly = {
 
 int __init addrconf_init(void)
 {
-	struct inet6_dev *idev;
+	struct inet6_dev *idev, *bdev;
 	int i, err;
 
 	err = ipv6_addr_label_init();
@@ -7036,10 +7036,14 @@ int __init addrconf_init(void)
 	 */
 	rtnl_lock();
 	idev = ipv6_add_dev(init_net.loopback_dev);
+	bdev = ipv6_add_dev(blackhole_netdev);
 	rtnl_unlock();
 	if (IS_ERR(idev)) {
 		err = PTR_ERR(idev);
 		goto errlo;
+	} else if (IS_ERR(bdev)) {
+		err = PTR_ERR(bdev);
+		goto errlo;
 	}
 
 	ip6_route_init_special_entries();
@@ -7124,6 +7128,7 @@ void addrconf_cleanup(void)
 		addrconf_ifdown(dev, 1);
 	}
 	addrconf_ifdown(init_net.loopback_dev, 2);
+	addrconf_ifdown(blackhole_netdev, 2);
 
 	/*
 	 *	Check hash table.
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 546088e508151..23164ac42826e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -155,10 +155,9 @@ void rt6_uncached_list_del(struct rt6_info *rt)
 
 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 {
-	struct net_device *loopback_dev = net->loopback_dev;
 	int cpu;
 
-	if (dev == loopback_dev)
+	if (dev == net->loopback_dev)
 		return;
 
 	for_each_possible_cpu(cpu) {
@@ -171,7 +170,7 @@ static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 			struct net_device *rt_dev = rt->dst.dev;
 
 			if (rt_idev->dev == dev) {
-				rt->rt6i_idev = in6_dev_get(loopback_dev);
+				rt->rt6i_idev = in6_dev_get(blackhole_netdev);
 				in6_dev_put(rt_idev);
 			}
 
@@ -386,13 +385,11 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 {
 	struct rt6_info *rt = (struct rt6_info *)dst;
 	struct inet6_dev *idev = rt->rt6i_idev;
-	struct net_device *loopback_dev =
-		dev_net(dev)->loopback_dev;
 
-	if (idev && idev->dev != loopback_dev) {
-		struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
-		if (loopback_idev) {
-			rt->rt6i_idev = loopback_idev;
+	if (idev && idev->dev != dev_net(dev)->loopback_dev) {
+		struct inet6_dev *ibdev = in6_dev_get(blackhole_netdev);
+		if (ibdev) {
+			rt->rt6i_idev = ibdev;
 			in6_dev_put(idev);
 		}
 	}
-- 
2.20.1

[PATCH AUTOSEL 5.3 13/33] net: usb: sr9800: fix uninitialized local variable

[Sasha Levin]

From: Valentin Vidic <vvidic@valentin-vidic.from.hr>

[ Upstream commit 77b6d09f4ae66d42cd63b121af67780ae3d1a5e9 ]

Make sure res does not contain random value if the call to
sr_read_cmd fails for some reason.

Reported-by: syzbot+f1842130bbcfb335bac1@syzkaller.appspotmail.com
Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/usb/sr9800.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/usb/sr9800.c b/drivers/net/usb/sr9800.c
index 35f39f23d8814..8f8c9ede88c26 100644
--- a/drivers/net/usb/sr9800.c
+++ b/drivers/net/usb/sr9800.c
@@ -336,7 +336,7 @@ static void sr_set_multicast(struct net_device *net)
 static int sr_mdio_read(struct net_device *net, int phy_id, int loc)
 {
 	struct usbnet *dev = netdev_priv(net);
-	__le16 res;
+	__le16 res = 0;
 
 	mutex_lock(&dev->phy_mutex);
 	sr_set_sw_mii(dev);
-- 
2.20.1

[PATCH AUTOSEL 5.3 16/33] netfilter: connlabels: prefer static lock initialiser

[Sasha Levin]

From: Florian Westphal <fw@strlen.de>

[ Upstream commit 105333435b4f3b21ffc325f32fae17719310db64 ]

seen during boot:
BUG: spinlock bad magic on CPU#2, swapper/0/1
 lock: nf_connlabels_lock+0x0/0x60, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Call Trace:
 do_raw_spin_lock+0x14e/0x1b0
 nf_connlabels_get+0x15/0x40
 ct_init_net+0xc4/0x270
 ops_init+0x56/0x1c0
 register_pernet_operations+0x1c8/0x350
 register_pernet_subsys+0x1f/0x40
 tcf_register_action+0x7c/0x1a0
 do_one_initcall+0x13d/0x2d9

Problem is that ct action init function can run before
connlabels_init().  Lock has not been initialised yet.

Fix it by using a static initialiser.

Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nf_conntrack_labels.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/netfilter/nf_conntrack_labels.c b/net/netfilter/nf_conntrack_labels.c
index 74b8113f7aebe..d1c6b2a2e7bd1 100644
--- a/net/netfilter/nf_conntrack_labels.c
+++ b/net/netfilter/nf_conntrack_labels.c
@@ -11,7 +11,7 @@
 #include <net/netfilter/nf_conntrack_ecache.h>
 #include <net/netfilter/nf_conntrack_labels.h>
 
-static spinlock_t nf_connlabels_lock;
+static __read_mostly DEFINE_SPINLOCK(nf_connlabels_lock);
 
 static int replace_u32(u32 *address, u32 mask, u32 new)
 {
@@ -89,7 +89,6 @@ int nf_conntrack_labels_init(void)
 {
 	BUILD_BUG_ON(NF_CT_LABELS_MAX_SIZE / sizeof(long) >= U8_MAX);
 
-	spin_lock_init(&nf_connlabels_lock);
 	return nf_ct_extend_register(&labels_extend);
 }
 
-- 
2.20.1

[PATCH AUTOSEL 5.3 19/33] net/rds: Whitelist rdma_cookie and rx_tstamp for usercopy

[Sasha Levin]

From: Dag Moxnes <dag.moxnes@oracle.com>

[ Upstream commit bf1867db9b850fff2dd54a1a117a684a10b8cd90 ]

Add the RDMA cookie and RX timestamp to the usercopy whitelist.

After the introduction of hardened usercopy whitelisting
(https://lwn.net/Articles/727322/), a warning is displayed when the
RDMA cookie or RX timestamp is copied to userspace:

kernel: WARNING: CPU: 3 PID: 5750 at
mm/usercopy.c:81 usercopy_warn+0x8e/0xa6
[...]
kernel: Call Trace:
kernel: __check_heap_object+0xb8/0x11b
kernel: __check_object_size+0xe3/0x1bc
kernel: put_cmsg+0x95/0x115
kernel: rds_recvmsg+0x43d/0x620 [rds]
kernel: sock_recvmsg+0x43/0x4a
kernel: ___sys_recvmsg+0xda/0x1e6
kernel: ? __handle_mm_fault+0xcae/0xf79
kernel: __sys_recvmsg+0x51/0x8a
kernel: SyS_recvmsg+0x12/0x1c
kernel: do_syscall_64+0x79/0x1ae

When the whitelisting feature was introduced, the memory for the RDMA
cookie and RX timestamp in RDS was not added to the whitelist, causing
the warning above.

Signed-off-by: Dag Moxnes <dag.moxnes@oracle.com>
Tested-by: Jenny <jenny.x.xu@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rds/ib_recv.c | 11 ++++++++---
 net/rds/rds.h     |  9 +++++++--
 net/rds/recv.c    | 22 ++++++++++++----------
 3 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/net/rds/ib_recv.c b/net/rds/ib_recv.c
index 3cae88cbdaa02..fecd0abdc7e8e 100644
--- a/net/rds/ib_recv.c
+++ b/net/rds/ib_recv.c
@@ -1038,9 +1038,14 @@ int rds_ib_recv_init(void)
 	si_meminfo(&si);
 	rds_ib_sysctl_max_recv_allocation = si.totalram / 3 * PAGE_SIZE / RDS_FRAG_SIZE;
 
-	rds_ib_incoming_slab = kmem_cache_create("rds_ib_incoming",
-					sizeof(struct rds_ib_incoming),
-					0, SLAB_HWCACHE_ALIGN, NULL);
+	rds_ib_incoming_slab =
+		kmem_cache_create_usercopy("rds_ib_incoming",
+					   sizeof(struct rds_ib_incoming),
+					   0, SLAB_HWCACHE_ALIGN,
+					   offsetof(struct rds_ib_incoming,
+						    ii_inc.i_usercopy),
+					   sizeof(struct rds_inc_usercopy),
+					   NULL);
 	if (!rds_ib_incoming_slab)
 		goto out;
 
diff --git a/net/rds/rds.h b/net/rds/rds.h
index f0066d1684993..e792a67dd5788 100644
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -271,6 +271,12 @@ struct rds_ext_header_rdma_dest {
 #define	RDS_MSG_RX_END		2
 #define	RDS_MSG_RX_CMSG		3
 
+/* The following values are whitelisted for usercopy */
+struct rds_inc_usercopy {
+	rds_rdma_cookie_t	rdma_cookie;
+	ktime_t			rx_tstamp;
+};
+
 struct rds_incoming {
 	refcount_t		i_refcount;
 	struct list_head	i_item;
@@ -280,8 +286,7 @@ struct rds_incoming {
 	unsigned long		i_rx_jiffies;
 	struct in6_addr		i_saddr;
 
-	rds_rdma_cookie_t	i_rdma_cookie;
-	ktime_t			i_rx_tstamp;
+	struct rds_inc_usercopy i_usercopy;
 	u64			i_rx_lat_trace[RDS_RX_MAX_TRACES];
 };
 
diff --git a/net/rds/recv.c b/net/rds/recv.c
index a42ba7fa06d5d..c8404971d5ab3 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -47,8 +47,8 @@ void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
 	INIT_LIST_HEAD(&inc->i_item);
 	inc->i_conn = conn;
 	inc->i_saddr = *saddr;
-	inc->i_rdma_cookie = 0;
-	inc->i_rx_tstamp = ktime_set(0, 0);
+	inc->i_usercopy.rdma_cookie = 0;
+	inc->i_usercopy.rx_tstamp = ktime_set(0, 0);
 
 	memset(inc->i_rx_lat_trace, 0, sizeof(inc->i_rx_lat_trace));
 }
@@ -62,8 +62,8 @@ void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *cp,
 	inc->i_conn = cp->cp_conn;
 	inc->i_conn_path = cp;
 	inc->i_saddr = *saddr;
-	inc->i_rdma_cookie = 0;
-	inc->i_rx_tstamp = ktime_set(0, 0);
+	inc->i_usercopy.rdma_cookie = 0;
+	inc->i_usercopy.rx_tstamp = ktime_set(0, 0);
 }
 EXPORT_SYMBOL_GPL(rds_inc_path_init);
 
@@ -186,7 +186,7 @@ static void rds_recv_incoming_exthdrs(struct rds_incoming *inc, struct rds_sock
 		case RDS_EXTHDR_RDMA_DEST:
 			/* We ignore the size for now. We could stash it
 			 * somewhere and use it for error checking. */
-			inc->i_rdma_cookie = rds_rdma_make_cookie(
+			inc->i_usercopy.rdma_cookie = rds_rdma_make_cookie(
 					be32_to_cpu(buffer.rdma_dest.h_rdma_rkey),
 					be32_to_cpu(buffer.rdma_dest.h_rdma_offset));
 
@@ -380,7 +380,7 @@ void rds_recv_incoming(struct rds_connection *conn, struct in6_addr *saddr,
 				      be32_to_cpu(inc->i_hdr.h_len),
 				      inc->i_hdr.h_dport);
 		if (sock_flag(sk, SOCK_RCVTSTAMP))
-			inc->i_rx_tstamp = ktime_get_real();
+			inc->i_usercopy.rx_tstamp = ktime_get_real();
 		rds_inc_addref(inc);
 		inc->i_rx_lat_trace[RDS_MSG_RX_END] = local_clock();
 		list_add_tail(&inc->i_item, &rs->rs_recv_queue);
@@ -540,16 +540,18 @@ static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg,
 {
 	int ret = 0;
 
-	if (inc->i_rdma_cookie) {
+	if (inc->i_usercopy.rdma_cookie) {
 		ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RDMA_DEST,
-				sizeof(inc->i_rdma_cookie), &inc->i_rdma_cookie);
+				sizeof(inc->i_usercopy.rdma_cookie),
+				&inc->i_usercopy.rdma_cookie);
 		if (ret)
 			goto out;
 	}
 
-	if ((inc->i_rx_tstamp != 0) &&
+	if ((inc->i_usercopy.rx_tstamp != 0) &&
 	    sock_flag(rds_rs_to_sk(rs), SOCK_RCVTSTAMP)) {
-		struct __kernel_old_timeval tv = ns_to_kernel_old_timeval(inc->i_rx_tstamp);
+		struct __kernel_old_timeval tv =
+			ns_to_kernel_old_timeval(inc->i_usercopy.rx_tstamp);
 
 		if (!sock_flag(rds_rs_to_sk(rs), SOCK_TSTAMP_NEW)) {
 			ret = put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
-- 
2.20.1

[PATCH AUTOSEL 5.3 21/33] ath9k: dynack: fix possible deadlock in ath_dynack_node_{de}init

[Sasha Levin]

From: Lorenzo Bianconi <lorenzo@kernel.org>

[ Upstream commit e1aa1a1db3b01c9890e82cf065cee99962ba1ed9 ]

Fix following lockdep warning disabling bh in
ath_dynack_node_init/ath_dynack_node_deinit

[   75.955878] --------------------------------
[   75.955880] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   75.955884] swapper/0/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
[   75.955888] 00000000792a7ee0 (&(&da->qlock)->rlock){+.?.}, at: ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[   75.955905] {SOFTIRQ-ON-W} state was registered at:
[   75.955912]   lock_acquire+0x9a/0x160
[   75.955917]   _raw_spin_lock+0x2c/0x70
[   75.955927]   ath_dynack_node_init+0x2a/0x60 [ath9k_hw]
[   75.955934]   ath9k_sta_state+0xec/0x160 [ath9k]
[   75.955976]   drv_sta_state+0xb2/0x740 [mac80211]
[   75.956008]   sta_info_insert_finish+0x21a/0x420 [mac80211]
[   75.956039]   sta_info_insert_rcu+0x12b/0x2c0 [mac80211]
[   75.956069]   sta_info_insert+0x7/0x70 [mac80211]
[   75.956093]   ieee80211_prep_connection+0x42e/0x730 [mac80211]
[   75.956120]   ieee80211_mgd_auth.cold+0xb9/0x15c [mac80211]
[   75.956152]   cfg80211_mlme_auth+0x143/0x350 [cfg80211]
[   75.956169]   nl80211_authenticate+0x25e/0x2b0 [cfg80211]
[   75.956172]   genl_family_rcv_msg+0x198/0x400
[   75.956174]   genl_rcv_msg+0x42/0x90
[   75.956176]   netlink_rcv_skb+0x35/0xf0
[   75.956178]   genl_rcv+0x1f/0x30
[   75.956180]   netlink_unicast+0x154/0x200
[   75.956182]   netlink_sendmsg+0x1bf/0x3d0
[   75.956186]   ___sys_sendmsg+0x2c2/0x2f0
[   75.956187]   __sys_sendmsg+0x44/0x80
[   75.956190]   do_syscall_64+0x55/0x1a0
[   75.956192]   entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   75.956194] irq event stamp: 2357092
[   75.956196] hardirqs last  enabled at (2357092): [<ffffffff818c62de>] _raw_spin_unlock_irqrestore+0x3e/0x50
[   75.956199] hardirqs last disabled at (2357091): [<ffffffff818c60b1>] _raw_spin_lock_irqsave+0x11/0x80
[   75.956202] softirqs last  enabled at (2357072): [<ffffffff8106dc09>] irq_enter+0x59/0x60
[   75.956204] softirqs last disabled at (2357073): [<ffffffff8106dcbe>] irq_exit+0xae/0xc0
[   75.956206]
               other info that might help us debug this:
[   75.956207]  Possible unsafe locking scenario:

[   75.956208]        CPU0
[   75.956209]        ----
[   75.956210]   lock(&(&da->qlock)->rlock);
[   75.956213]   <Interrupt>
[   75.956214]     lock(&(&da->qlock)->rlock);
[   75.956216]
                *** DEADLOCK ***

[   75.956217] 1 lock held by swapper/0/0:
[   75.956219]  #0: 000000003bb5675c (&(&sc->sc_pcu_lock)->rlock){+.-.}, at: ath9k_tasklet+0x55/0x240 [ath9k]
[   75.956225]
               stack backtrace:
[   75.956228] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc1-wdn+ #13
[   75.956229] Hardware name: Dell Inc. Studio XPS 1340/0K183D, BIOS A11 09/08/2009
[   75.956231] Call Trace:
[   75.956233]  <IRQ>
[   75.956236]  dump_stack+0x67/0x90
[   75.956239]  mark_lock+0x4c1/0x640
[   75.956242]  ? check_usage_backwards+0x130/0x130
[   75.956245]  ? sched_clock_local+0x12/0x80
[   75.956247]  __lock_acquire+0x484/0x7a0
[   75.956250]  ? __lock_acquire+0x3b9/0x7a0
[   75.956252]  lock_acquire+0x9a/0x160
[   75.956259]  ? ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[   75.956262]  _raw_spin_lock_bh+0x34/0x80
[   75.956268]  ? ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[   75.956275]  ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[   75.956280]  ath_rx_tasklet+0xd09/0xe90 [ath9k]
[   75.956286]  ath9k_tasklet+0x102/0x240 [ath9k]
[   75.956288]  tasklet_action_common.isra.0+0x6d/0x170
[   75.956291]  __do_softirq+0xcc/0x425
[   75.956294]  irq_exit+0xae/0xc0
[   75.956296]  do_IRQ+0x8a/0x110
[   75.956298]  common_interrupt+0xf/0xf
[   75.956300]  </IRQ>
[   75.956303] RIP: 0010:cpuidle_enter_state+0xb2/0x400
[   75.956308] RSP: 0018:ffffffff82203e70 EFLAGS: 00000202 ORIG_RAX: ffffffffffffffd7
[   75.956310] RAX: ffffffff82219800 RBX: ffffffff822bd0a0 RCX: 0000000000000000
[   75.956312] RDX: 0000000000000046 RSI: 0000000000000006 RDI: ffffffff82219800
[   75.956314] RBP: ffff888155a01c00 R08: 00000011af51aabe R09: 0000000000000000
[   75.956315] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
[   75.956317] R13: 00000011af51aabe R14: 0000000000000003 R15: ffffffff82219800
[   75.956321]  cpuidle_enter+0x24/0x40
[   75.956323]  do_idle+0x1ac/0x220
[   75.956326]  cpu_startup_entry+0x14/0x20
[   75.956329]  start_kernel+0x482/0x489
[   75.956332]  secondary_startup_64+0xa4/0xb0

Fixes: c774d57fd47c ("ath9k: add dynamic ACK timeout estimation")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/ath/ath9k/dynack.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/dynack.c b/drivers/net/wireless/ath/ath9k/dynack.c
index f112fa5b2eacf..1ccf20d8c1607 100644
--- a/drivers/net/wireless/ath/ath9k/dynack.c
+++ b/drivers/net/wireless/ath/ath9k/dynack.c
@@ -298,9 +298,9 @@ void ath_dynack_node_init(struct ath_hw *ah, struct ath_node *an)
 
 	an->ackto = ackto;
 
-	spin_lock(&da->qlock);
+	spin_lock_bh(&da->qlock);
 	list_add_tail(&an->list, &da->nodes);
-	spin_unlock(&da->qlock);
+	spin_unlock_bh(&da->qlock);
 }
 EXPORT_SYMBOL(ath_dynack_node_init);
 
@@ -314,9 +314,9 @@ void ath_dynack_node_deinit(struct ath_hw *ah, struct ath_node *an)
 {
 	struct ath_dynack *da = &ah->dynack;
 
-	spin_lock(&da->qlock);
+	spin_lock_bh(&da->qlock);
 	list_del(&an->list);
-	spin_unlock(&da->qlock);
+	spin_unlock_bh(&da->qlock);
 }
 EXPORT_SYMBOL(ath_dynack_node_deinit);
 
-- 
2.20.1

[PATCH AUTOSEL 5.3 25/33] net: sched: sch_htb: don't call qdisc_put() while holding tree lock

[Sasha Levin]

From: Vlad Buslov <vladbu@mellanox.com>

[ Upstream commit 4ce70b4aed5752332b268909336b351721965dc4 ]

Recent changes that removed rtnl dependency from rules update path of tc
also made tcf_block_put() function sleeping. This function is called from
ops->destroy() of several Qdisc implementations, which in turn is called by
qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock,
which results sleeping-while-atomic BUG.

Steps to reproduce for htb:

tc qdisc add dev ens1f0 root handle 1: htb default 12
tc class add dev ens1f0 parent 1: classid 1:1 htb rate 100kbps ceil 100kbps
tc qdisc add dev ens1f0 parent 1:1 handle 40: sfq perturb 10
tc class add dev ens1f0 parent 1:1 classid 1:2 htb rate 100kbps ceil 100kbps

Resulting dmesg:

[ 4791.148551] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909
[ 4791.151354] in_atomic(): 1, irqs_disabled(): 0, pid: 27273, name: tc
[ 4791.152805] INFO: lockdep is turned off.
[ 4791.153605] CPU: 19 PID: 27273 Comm: tc Tainted: G        W         5.3.0-rc8+ #721
[ 4791.154336] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 4791.155075] Call Trace:
[ 4791.155803]  dump_stack+0x85/0xc0
[ 4791.156529]  ___might_sleep.cold+0xac/0xbc
[ 4791.157251]  __mutex_lock+0x5b/0x960
[ 4791.157966]  ? console_unlock+0x363/0x5d0
[ 4791.158676]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.159395]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.160103]  tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.160815]  tcf_block_put_ext.part.0+0x21/0x50
[ 4791.161530]  tcf_block_put+0x50/0x70
[ 4791.162233]  sfq_destroy+0x15/0x50 [sch_sfq]
[ 4791.162936]  qdisc_destroy+0x5f/0x160
[ 4791.163642]  htb_change_class.cold+0x5df/0x69d [sch_htb]
[ 4791.164505]  tc_ctl_tclass+0x19d/0x480
[ 4791.165360]  rtnetlink_rcv_msg+0x170/0x4b0
[ 4791.166191]  ? netlink_deliver_tap+0x95/0x400
[ 4791.166907]  ? rtnl_dellink+0x2d0/0x2d0
[ 4791.167625]  netlink_rcv_skb+0x49/0x110
[ 4791.168345]  netlink_unicast+0x171/0x200
[ 4791.169058]  netlink_sendmsg+0x224/0x3f0
[ 4791.169771]  sock_sendmsg+0x5e/0x60
[ 4791.170475]  ___sys_sendmsg+0x2ae/0x330
[ 4791.171183]  ? ___sys_recvmsg+0x159/0x1f0
[ 4791.171894]  ? do_wp_page+0x9c/0x790
[ 4791.172595]  ? __handle_mm_fault+0xcd3/0x19e0
[ 4791.173309]  __sys_sendmsg+0x59/0xa0
[ 4791.174024]  do_syscall_64+0x5c/0xb0
[ 4791.174725]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 4791.175435] RIP: 0033:0x7f0aa41497b8
[ 4791.176129] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5
4
[ 4791.177532] RSP: 002b:00007fff4e37d588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 4791.178243] RAX: ffffffffffffffda RBX: 000000005d8132f7 RCX: 00007f0aa41497b8
[ 4791.178947] RDX: 0000000000000000 RSI: 00007fff4e37d5f0 RDI: 0000000000000003
[ 4791.179662] RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000020149a0
[ 4791.180382] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001
[ 4791.181100] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000

In htb_change_class() function save parent->leaf.q to local temporary
variable and put reference to it after sch tree lock is released in order
not to call potentially sleeping cls API in atomic section. This is safe to
do because Qdisc has already been reset by qdisc_purge_queue() inside sch
tree lock critical section.

Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sched/sch_htb.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 7bcf20ef91453..8184c87da8bec 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1302,6 +1302,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 	struct htb_class *cl = (struct htb_class *)*arg, *parent;
 	struct nlattr *opt = tca[TCA_OPTIONS];
 	struct nlattr *tb[TCA_HTB_MAX + 1];
+	struct Qdisc *parent_qdisc = NULL;
 	struct tc_htb_opt *hopt;
 	u64 rate64, ceil64;
 	int warn = 0;
@@ -1401,7 +1402,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 		if (parent && !parent->level) {
 			/* turn parent into inner node */
 			qdisc_purge_queue(parent->leaf.q);
-			qdisc_put(parent->leaf.q);
+			parent_qdisc = parent->leaf.q;
 			if (parent->prio_activity)
 				htb_deactivate(q, parent);
 
@@ -1480,6 +1481,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 	cl->cbuffer = PSCHED_TICKS2NS(hopt->cbuffer);
 
 	sch_tree_unlock(sch);
+	qdisc_put(parent_qdisc);
 
 	if (warn)
 		pr_warn("HTB: quantum of class %X is %s. Consider r2q change.\n",
-- 
2.20.1

[PATCH AUTOSEL 5.3 26/33] net: sched: multiq: don't call qdisc_put() while holding tree lock

[Sasha Levin]

From: Vlad Buslov <vladbu@mellanox.com>

[ Upstream commit c2999f7fb05b87da4060e38150c70fa46794d82b ]

Recent changes that removed rtnl dependency from rules update path of tc
also made tcf_block_put() function sleeping. This function is called from
ops->destroy() of several Qdisc implementations, which in turn is called by
qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock,
which results sleeping-while-atomic BUG.

Steps to reproduce for multiq:

tc qdisc add dev ens1f0 root handle 1: multiq
tc qdisc add dev ens1f0 parent 1:10 handle 50: sfq perturb 10
ethtool -L ens1f0 combined 2
tc qdisc change dev ens1f0 root handle 1: multiq

Resulting dmesg:

[ 5539.419344] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909
[ 5539.420945] in_atomic(): 1, irqs_disabled(): 0, pid: 27658, name: tc
[ 5539.422435] INFO: lockdep is turned off.
[ 5539.423904] CPU: 21 PID: 27658 Comm: tc Tainted: G        W         5.3.0-rc8+ #721
[ 5539.425400] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 5539.426911] Call Trace:
[ 5539.428380]  dump_stack+0x85/0xc0
[ 5539.429823]  ___might_sleep.cold+0xac/0xbc
[ 5539.431262]  __mutex_lock+0x5b/0x960
[ 5539.432682]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 5539.434103]  ? __nla_validate_parse+0x51/0x840
[ 5539.435493]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 5539.436903]  tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 5539.438327]  tcf_block_put_ext.part.0+0x21/0x50
[ 5539.439752]  tcf_block_put+0x50/0x70
[ 5539.441165]  sfq_destroy+0x15/0x50 [sch_sfq]
[ 5539.442570]  qdisc_destroy+0x5f/0x160
[ 5539.444000]  multiq_tune+0x14a/0x420 [sch_multiq]
[ 5539.445421]  tc_modify_qdisc+0x324/0x840
[ 5539.446841]  rtnetlink_rcv_msg+0x170/0x4b0
[ 5539.448269]  ? netlink_deliver_tap+0x95/0x400
[ 5539.449691]  ? rtnl_dellink+0x2d0/0x2d0
[ 5539.451116]  netlink_rcv_skb+0x49/0x110
[ 5539.452522]  netlink_unicast+0x171/0x200
[ 5539.453914]  netlink_sendmsg+0x224/0x3f0
[ 5539.455304]  sock_sendmsg+0x5e/0x60
[ 5539.456686]  ___sys_sendmsg+0x2ae/0x330
[ 5539.458071]  ? ___sys_recvmsg+0x159/0x1f0
[ 5539.459461]  ? do_wp_page+0x9c/0x790
[ 5539.460846]  ? __handle_mm_fault+0xcd3/0x19e0
[ 5539.462263]  __sys_sendmsg+0x59/0xa0
[ 5539.463661]  do_syscall_64+0x5c/0xb0
[ 5539.465044]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 5539.466454] RIP: 0033:0x7f1fe08177b8
[ 5539.467863] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5
4
[ 5539.470906] RSP: 002b:00007ffe812de5d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 5539.472483] RAX: ffffffffffffffda RBX: 000000005d8135e3 RCX: 00007f1fe08177b8
[ 5539.474069] RDX: 0000000000000000 RSI: 00007ffe812de640 RDI: 0000000000000003
[ 5539.475655] RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000182e9b0
[ 5539.477203] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001
[ 5539.478699] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000

Rearrange locking in multiq_tune() in following ways:

- In loop that removes Qdiscs from disabled queues, call
  qdisc_purge_queue() instead of qdisc_tree_flush_backlog() on Qdisc that
  is being destroyed. Save the Qdisc in temporary allocated array and call
  qdisc_put() on each element of the array after sch tree lock is released.
  This is safe to do because Qdiscs have already been reset by
  qdisc_purge_queue() inside sch tree lock critical section.

- Do the same change for second loop that initializes Qdiscs for newly
  enabled queues in multiq_tune() function. Since sch tree lock is obtained
  and released on each iteration of this loop, just call qdisc_put()
  directly outside of critical section. Don't verify that old Qdisc is not
  noop_qdisc before releasing reference to it because such check is already
  performed by qdisc_put*() functions.

Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sched/sch_multiq.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
index e1087746f6a29..b2b7fdb06fc62 100644
--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -174,7 +174,8 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
 {
 	struct multiq_sched_data *q = qdisc_priv(sch);
 	struct tc_multiq_qopt *qopt;
-	int i;
+	struct Qdisc **removed;
+	int i, n_removed = 0;
 
 	if (!netif_is_multiqueue(qdisc_dev(sch)))
 		return -EOPNOTSUPP;
@@ -185,6 +186,11 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
 
 	qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
 
+	removed = kmalloc(sizeof(*removed) * (q->max_bands - q->bands),
+			  GFP_KERNEL);
+	if (!removed)
+		return -ENOMEM;
+
 	sch_tree_lock(sch);
 	q->bands = qopt->bands;
 	for (i = q->bands; i < q->max_bands; i++) {
@@ -192,13 +198,17 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
 			struct Qdisc *child = q->queues[i];
 
 			q->queues[i] = &noop_qdisc;
-			qdisc_tree_flush_backlog(child);
-			qdisc_put(child);
+			qdisc_purge_queue(child);
+			removed[n_removed++] = child;
 		}
 	}
 
 	sch_tree_unlock(sch);
 
+	for (i = 0; i < n_removed; i++)
+		qdisc_put(removed[i]);
+	kfree(removed);
+
 	for (i = 0; i < q->bands; i++) {
 		if (q->queues[i] == &noop_qdisc) {
 			struct Qdisc *child, *old;
@@ -213,11 +223,10 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
 				if (child != &noop_qdisc)
 					qdisc_hash_add(child, true);
 
-				if (old != &noop_qdisc) {
-					qdisc_tree_flush_backlog(old);
-					qdisc_put(old);
-				}
+				if (old != &noop_qdisc)
+					qdisc_purge_queue(old);
 				sch_tree_unlock(sch);
+				qdisc_put(old);
 			}
 		}
 	}
-- 
2.20.1

[PATCH AUTOSEL 5.3 29/33] ipv6: Handle race in addrconf_dad_work

[Sasha Levin]

From: David Ahern <dsahern@gmail.com>

[ Upstream commit a3ce2a21bb8969ae27917281244fa91bf5f286d7 ]

Rajendra reported a kernel panic when a link was taken down:

[ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
[ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290

<snip>

[ 6870.570501] Call Trace:
[ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40
[ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0
[ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260
[ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430
[ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430
[ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490
[ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430
[ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0
[ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60
[ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70
[ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0

addrconf_dad_work is kicked to be scheduled when a device is brought
up. There is a race between addrcond_dad_work getting scheduled and
taking the rtnl lock and a process taking the link down (under rtnl).
The latter removes the host route from the inet6_addr as part of
addrconf_ifdown which is run for NETDEV_DOWN. The former attempts
to use the host route in ipv6_ifa_notify. If the down event removes
the host route due to the race to the rtnl, then the BUG listed above
occurs.

This scenario does not occur when the ipv6 address is not kept
(net.ipv6.conf.all.keep_addr_on_down = 0) as addrconf_ifdown sets the
state of the ifp to DEAD. Handle when the addresses are kept by checking
IF_READY which is reset by addrconf_ifdown.

The 'dead' flag for an inet6_addr is set only under rtnl, in
addrconf_ifdown and it means the device is getting removed (or IPv6 is
disabled). The interesting cases for changing the idev flag are
addrconf_notify (NETDEV_UP and NETDEV_CHANGE) and addrconf_ifdown
(reset the flag). The former does not have the idev lock - only rtnl;
the latter has both. Based on that the existing dead + IF_READY check
can be moved to right after the rtnl_lock in addrconf_dad_work.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv6/addrconf.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 4c87594d1389d..10093b8dd5483 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -4032,6 +4032,12 @@ static void addrconf_dad_work(struct work_struct *w)
 
 	rtnl_lock();
 
+	/* check if device was taken down before this delayed work
+	 * function could be canceled
+	 */
+	if (idev->dead || !(idev->if_flags & IF_READY))
+		goto out;
+
 	spin_lock_bh(&ifp->lock);
 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
 		action = DAD_BEGIN;
@@ -4077,11 +4083,6 @@ static void addrconf_dad_work(struct work_struct *w)
 		goto out;
 
 	write_lock_bh(&idev->lock);
-	if (idev->dead || !(idev->if_flags & IF_READY)) {
-		write_unlock_bh(&idev->lock);
-		goto out;
-	}
-
 	spin_lock(&ifp->lock);
 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
 		spin_unlock(&ifp->lock);
-- 
2.20.1

[PATCH AUTOSEL 5.3 31/33] sctp: add chunks to sk_backlog when the newsk sk_socket is not set

[Sasha Levin]

From: Xin Long <lucien.xin@gmail.com>

[ Upstream commit 819be8108fded0b9e710bbbf81193e52f7bab2f7 ]

This patch is to fix a NULL-ptr deref in selinux_socket_connect_helper:

  [...] kasan: GPF could be caused by NULL-ptr deref or user memory access
  [...] RIP: 0010:selinux_socket_connect_helper+0x94/0x460
  [...] Call Trace:
  [...]  selinux_sctp_bind_connect+0x16a/0x1d0
  [...]  security_sctp_bind_connect+0x58/0x90
  [...]  sctp_process_asconf+0xa52/0xfd0 [sctp]
  [...]  sctp_sf_do_asconf+0x785/0x980 [sctp]
  [...]  sctp_do_sm+0x175/0x5a0 [sctp]
  [...]  sctp_assoc_bh_rcv+0x285/0x5b0 [sctp]
  [...]  sctp_backlog_rcv+0x482/0x910 [sctp]
  [...]  __release_sock+0x11e/0x310
  [...]  release_sock+0x4f/0x180
  [...]  sctp_accept+0x3f9/0x5a0 [sctp]
  [...]  inet_accept+0xe7/0x720

It was caused by that the 'newsk' sk_socket was not set before going to
security sctp hook when processing asconf chunk with SCTP_PARAM_ADD_IP
or SCTP_PARAM_SET_PRIMARY:

  inet_accept()->
    sctp_accept():
      lock_sock():
          lock listening 'sk'
                                          do_softirq():
                                            sctp_rcv():  <-- [1]
                                                asconf chunk arrives and
                                                enqueued in 'sk' backlog
      sctp_sock_migrate():
          set asoc's sk to 'newsk'
      release_sock():
          sctp_backlog_rcv():
            lock 'newsk'
            sctp_process_asconf()  <-- [2]
            unlock 'newsk'
    sock_graft():
        set sk_socket  <-- [3]

As it shows, at [1] the asconf chunk would be put into the listening 'sk'
backlog, as accept() was holding its sock lock. Then at [2] asconf would
get processed with 'newsk' as asoc's sk had been set to 'newsk'. However,
'newsk' sk_socket is not set until [3], while selinux_sctp_bind_connect()
would deref it, then kernel crashed.

Here to fix it by adding the chunk to sk_backlog until newsk sk_socket is
set when .accept() is done.

Note that sk->sk_socket can be NULL when the sock is closed, so SOCK_DEAD
flag is also needed to check in sctp_newsk_ready().

Thanks to Ondrej for reviewing the code.

Fixes: d452930fd3b9 ("selinux: Add SCTP support")
Reported-by: Ying Xu <yinxu@redhat.com>
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/sctp/sctp.h |  5 +++++
 net/sctp/input.c        | 12 +++++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 5d60f13d2347b..3ab5c6bbb90bd 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -610,4 +610,9 @@ static inline __u32 sctp_min_frag_point(struct sctp_sock *sp, __u16 datasize)
 	return sctp_mtu_payload(sp, SCTP_DEFAULT_MINSEGMENT, datasize);
 }
 
+static inline bool sctp_newsk_ready(const struct sock *sk)
+{
+	return sock_flag(sk, SOCK_DEAD) || sk->sk_socket;
+}
+
 #endif /* __net_sctp_h__ */
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 1008cdc44dd61..156e24ad54ea4 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -243,7 +243,7 @@ int sctp_rcv(struct sk_buff *skb)
 		bh_lock_sock(sk);
 	}
 
-	if (sock_owned_by_user(sk)) {
+	if (sock_owned_by_user(sk) || !sctp_newsk_ready(sk)) {
 		if (sctp_add_backlog(sk, skb)) {
 			bh_unlock_sock(sk);
 			sctp_chunk_free(chunk);
@@ -321,7 +321,7 @@ int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 		local_bh_disable();
 		bh_lock_sock(sk);
 
-		if (sock_owned_by_user(sk)) {
+		if (sock_owned_by_user(sk) || !sctp_newsk_ready(sk)) {
 			if (sk_add_backlog(sk, skb, sk->sk_rcvbuf))
 				sctp_chunk_free(chunk);
 			else
@@ -336,7 +336,13 @@ int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 		if (backloged)
 			return 0;
 	} else {
-		sctp_inq_push(inqueue, chunk);
+		if (!sctp_newsk_ready(sk)) {
+			if (!sk_add_backlog(sk, skb, sk->sk_rcvbuf))
+				return 0;
+			sctp_chunk_free(chunk);
+		} else {
+			sctp_inq_push(inqueue, chunk);
+		}
 	}
 
 done:
-- 
2.20.1

Re: [PATCH AUTOSEL 5.3 12/33] blackhole_netdev: fix syzkaller reported issue

[Sasha Levin]

On Fri, Oct 25, 2019 at 09:54:44AM -0400, Sasha Levin wrote:
>From: Mahesh Bandewar <maheshb@google.com>
>
>[ Upstream commit b0818f80c8c1bc215bba276bd61c216014fab23b ]
>
>While invalidating the dst, we assign backhole_netdev instead of
>loopback device. However, this device does not have idev pointer
>and hence no ip6_ptr even if IPv6 is enabled. Possibly this has
>triggered the syzbot reported crash.
>
>The syzbot report does not have reproducer, however, this is the
>only device that doesn't have matching idev created.
>
>Crash instruction is :
>
>static inline bool ip6_ignore_linkdown(const struct net_device *dev)
>{
>        const struct inet6_dev *idev = __in6_dev_get(dev);
>
>        return !!idev->cnf.ignore_routes_with_linkdown; <= crash
>}
>
>Also ipv6 always assumes presence of idev and never checks for it
>being NULL (as does the above referenced code). So adding a idev
>for the blackhole_netdev to avoid this class of crashes in the future.
>
>Signed-off-by: David S. Miller <davem@davemloft.net>
>Signed-off-by: Sasha Levin <sashal@kernel.org>

I've dropped this patch.

-- 
Thanks,
Sasha