--- /dev/null
+From 0665886ad1392e6b5bae85d7a6ccbed48dca1522 Mon Sep 17 00:00:00 2001
+From: Takashi Iwai <tiwai@suse.de>
+Date: Wed, 20 Apr 2022 15:02:47 +0200
+Subject: ALSA: usb-audio: Clear MIDI port active flag after draining
+
+From: Takashi Iwai <tiwai@suse.de>
+
+commit 0665886ad1392e6b5bae85d7a6ccbed48dca1522 upstream.
+
+When a rawmidi output stream is closed, it calls the drain at first,
+then does trigger-off only when the drain returns -ERESTARTSYS as a
+fallback. It implies that each driver should turn off the stream
+properly after the drain. Meanwhile, USB-audio MIDI interface didn't
+change the port->active flag after the drain. This may leave the
+output work picking up the port that is closed right now, which
+eventually leads to a use-after-free for the already released rawmidi
+object.
+
+This patch fixes the bug by properly clearing the port->active flag
+after the output drain.
+
+Reported-by: syzbot+70e777a39907d6d5fd0a@syzkaller.appspotmail.com
+Cc: <stable@vger.kernel.org>
+Link: https://lore.kernel.org/r/00000000000011555605dceaff03@google.com
+Link: https://lore.kernel.org/r/20220420130247.22062-1-tiwai@suse.de
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ sound/usb/midi.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/sound/usb/midi.c
++++ b/sound/usb/midi.c
+@@ -1210,6 +1210,7 @@ static void snd_usbmidi_output_drain(str
+ } while (drain_urbs && timeout);
+ finish_wait(&ep->drain_wait, &wait);
+ }
++ port->active = 0;
+ spin_unlock_irq(&ep->buffer_lock);
+ }
+
--- /dev/null
+From c89dffc70b340780e5b933832d8c3e045ef3791e Mon Sep 17 00:00:00 2001
+From: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
+Date: Mon, 18 Jan 2021 14:59:20 +0900
+Subject: tcp: Fix potential use-after-free due to double kfree()
+
+From: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
+
+commit c89dffc70b340780e5b933832d8c3e045ef3791e upstream.
+
+Receiving ACK with a valid SYN cookie, cookie_v4_check() allocates struct
+request_sock and then can allocate inet_rsk(req)->ireq_opt. After that,
+tcp_v4_syn_recv_sock() allocates struct sock and copies ireq_opt to
+inet_sk(sk)->inet_opt. Normally, tcp_v4_syn_recv_sock() inserts the full
+socket into ehash and sets NULL to ireq_opt. Otherwise,
+tcp_v4_syn_recv_sock() has to reset inet_opt by NULL and free the full
+socket.
+
+The commit 01770a1661657 ("tcp: fix race condition when creating child
+sockets from syncookies") added a new path, in which more than one cores
+create full sockets for the same SYN cookie. Currently, the core which
+loses the race frees the full socket without resetting inet_opt, resulting
+in that both sock_put() and reqsk_put() call kfree() for the same memory:
+
+ sock_put
+ sk_free
+ __sk_free
+ sk_destruct
+ __sk_destruct
+ sk->sk_destruct/inet_sock_destruct
+ kfree(rcu_dereference_protected(inet->inet_opt, 1));
+
+ reqsk_put
+ reqsk_free
+ __reqsk_free
+ req->rsk_ops->destructor/tcp_v4_reqsk_destructor
+ kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1));
+
+Calling kmalloc() between the double kfree() can lead to use-after-free, so
+this patch fixes it by setting NULL to inet_opt before sock_put().
+
+As a side note, this kind of issue does not happen for IPv6. This is
+because tcp_v6_syn_recv_sock() clones both ipv6_opt and pktopts which
+correspond to ireq_opt in IPv4.
+
+Fixes: 01770a166165 ("tcp: fix race condition when creating child sockets from syncookies")
+CC: Ricardo Dias <rdias@singlestore.com>
+Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
+Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com>
+Reviewed-by: Eric Dumazet <edumazet@google.com>
+Link: https://lore.kernel.org/r/20210118055920.82516-1-kuniyu@amazon.co.jp
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/ipv4/tcp_ipv4.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/net/ipv4/tcp_ipv4.c
++++ b/net/ipv4/tcp_ipv4.c
+@@ -1503,6 +1503,8 @@ struct sock *tcp_v4_syn_recv_sock(const
+ tcp_move_syn(newtp, req);
+ ireq->ireq_opt = NULL;
+ } else {
++ newinet->inet_opt = NULL;
++
+ if (!req_unhash && found_dup_sk) {
+ /* This code path should only be executed in the
+ * syncookie case only
+@@ -1510,8 +1512,6 @@ struct sock *tcp_v4_syn_recv_sock(const
+ bh_unlock_sock(newsk);
+ sock_put(newsk);
+ newsk = NULL;
+- } else {
+- newinet->inet_opt = NULL;
+ }
+ }
+ return newsk;
projects / thirdparty / kernel / stable-queue.git / commitdiff
