4.14-stable patches

added patches:
	tcp-fix-tcp_mtup_probe_success-vs-wrong-snd_cwnd.patch

diff --git a/queue-4.14/series b/queue-4.14/series
index 22ba86f7c62348537bb9f5e966cac42b5ac75a79..018928a5422b43fe96e638000a431b342ee6b8a0 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -216,3 +216,4 @@ md-raid0-ignore-raid0-layout-if-the-second-zone-has-only-one-device.patch
 mtd-cfi_cmdset_0002-move-and-rename-chip_check-chip_ready-chip_good_for_write.patch
 mtd-cfi_cmdset_0002-use-chip_ready-for-write-on-s29gl064n.patch
 pci-qcom-fix-unbalanced-phy-init-on-probe-errors.patch
+tcp-fix-tcp_mtup_probe_success-vs-wrong-snd_cwnd.patch

diff --git a/queue-4.14/tcp-fix-tcp_mtup_probe_success-vs-wrong-snd_cwnd.patch b/queue-4.14/tcp-fix-tcp_mtup_probe_success-vs-wrong-snd_cwnd.patch
new file mode 100644 (file)
index 0000000..6266456
--- /dev/null
+++ b/queue-4.14/tcp-fix-tcp_mtup_probe_success-vs-wrong-snd_cwnd.patch
@@ -0,0 +1,107 @@
+From 11825765291a93d8e7f44230da67b9f607c777bf Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Fri, 27 May 2022 14:28:29 -0700
+Subject: tcp: fix tcp_mtup_probe_success vs wrong snd_cwnd
+
+From: Eric Dumazet <edumazet@google.com>
+
+commit 11825765291a93d8e7f44230da67b9f607c777bf upstream.
+
+syzbot got a new report [1] finally pointing to a very old bug,
+added in initial support for MTU probing.
+
+tcp_mtu_probe() has checks about starting an MTU probe if
+tcp_snd_cwnd(tp) >= 11.
+
+But nothing prevents tcp_snd_cwnd(tp) to be reduced later
+and before the MTU probe succeeds.
+
+This bug would lead to potential zero-divides.
+
+Debugging added in commit 40570375356c ("tcp: add accessors
+to read/set tp->snd_cwnd") has paid off :)
+
+While we are at it, address potential overflows in this code.
+
+[1]
+WARNING: CPU: 1 PID: 14132 at include/net/tcp.h:1219 tcp_mtup_probe_success+0x366/0x570 net/ipv4/tcp_input.c:2712
+Modules linked in:
+CPU: 1 PID: 14132 Comm: syz-executor.2 Not tainted 5.18.0-syzkaller-07857-gbabf0bb978e3 #0
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+RIP: 0010:tcp_snd_cwnd_set include/net/tcp.h:1219 [inline]
+RIP: 0010:tcp_mtup_probe_success+0x366/0x570 net/ipv4/tcp_input.c:2712
+Code: 74 08 48 89 ef e8 da 80 17 f9 48 8b 45 00 65 48 ff 80 80 03 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 aa b0 c5 f8 <0f> 0b e9 16 fe ff ff 48 8b 4c 24 08 80 e1 07 38 c1 0f 8c c7 fc ff
+RSP: 0018:ffffc900079e70f8 EFLAGS: 00010287
+RAX: ffffffff88c0f7f6 RBX: ffff8880756e7a80 RCX: 0000000000040000
+RDX: ffffc9000c6c4000 RSI: 0000000000031f9e RDI: 0000000000031f9f
+RBP: 0000000000000000 R08: ffffffff88c0f606 R09: ffffc900079e7520
+R10: ffffed101011226d R11: 1ffff1101011226c R12: 1ffff1100eadcf50
+R13: ffff8880756e72c0 R14: 1ffff1100eadcf89 R15: dffffc0000000000
+FS:  00007f643236e700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
+CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
+CR2: 00007f1ab3f1e2a0 CR3: 0000000064fe7000 CR4: 00000000003506e0
+DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
+DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
+Call Trace:
+ <TASK>
+ tcp_clean_rtx_queue+0x223a/0x2da0 net/ipv4/tcp_input.c:3356
+ tcp_ack+0x1962/0x3c90 net/ipv4/tcp_input.c:3861
+ tcp_rcv_established+0x7c8/0x1ac0 net/ipv4/tcp_input.c:5973
+ tcp_v6_do_rcv+0x57b/0x1210 net/ipv6/tcp_ipv6.c:1476
+ sk_backlog_rcv include/net/sock.h:1061 [inline]
+ __release_sock+0x1d8/0x4c0 net/core/sock.c:2849
+ release_sock+0x5d/0x1c0 net/core/sock.c:3404
+ sk_stream_wait_memory+0x700/0xdc0 net/core/stream.c:145
+ tcp_sendmsg_locked+0x111d/0x3fc0 net/ipv4/tcp.c:1410
+ tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1448
+ sock_sendmsg_nosec net/socket.c:714 [inline]
+ sock_sendmsg net/socket.c:734 [inline]
+ __sys_sendto+0x439/0x5c0 net/socket.c:2119
+ __do_sys_sendto net/socket.c:2131 [inline]
+ __se_sys_sendto net/socket.c:2127 [inline]
+ __x64_sys_sendto+0xda/0xf0 net/socket.c:2127
+ do_syscall_x64 arch/x86/entry/common.c:50 [inline]
+ do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
+ entry_SYSCALL_64_after_hwframe+0x46/0xb0
+RIP: 0033:0x7f6431289109
+Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
+RSP: 002b:00007f643236e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
+RAX: ffffffffffffffda RBX: 00007f643139c100 RCX: 00007f6431289109
+RDX: 00000000d0d0c2ac RSI: 0000000020000080 RDI: 000000000000000a
+RBP: 00007f64312e308d R08: 0000000000000000 R09: 0000000000000000
+R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
+R13: 00007fff372533af R14: 00007f643236e300 R15: 0000000000022000
+
+Fixes: 5d424d5a674f ("[TCP]: MTU probing")
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Reported-by: syzbot <syzkaller@googlegroups.com>
+Acked-by: Yuchung Cheng <ycheng@google.com>
+Acked-by: Neal Cardwell <ncardwell@google.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/ipv4/tcp_input.c |   11 +++++++----
+ 1 file changed, 7 insertions(+), 4 deletions(-)
+
+--- a/net/ipv4/tcp_input.c
++++ b/net/ipv4/tcp_input.c
+@@ -2619,12 +2619,15 @@ static void tcp_mtup_probe_success(struc
+ {
+       struct tcp_sock *tp = tcp_sk(sk);
+       struct inet_connection_sock *icsk = inet_csk(sk);
++      u64 val;
+ 
+-      /* FIXME: breaks with very large cwnd */
+       tp->prior_ssthresh = tcp_current_ssthresh(sk);
+-      tp->snd_cwnd = tp->snd_cwnd *
+-                     tcp_mss_to_mtu(sk, tp->mss_cache) /
+-                     icsk->icsk_mtup.probe_size;
++
++      val = (u64)tp->snd_cwnd * tcp_mss_to_mtu(sk, tp->mss_cache);
++      do_div(val, icsk->icsk_mtup.probe_size);
++      WARN_ON_ONCE((u32)val != val);
++      tp->snd_cwnd = max_t(u32, 1U, val);
++
+       tp->snd_cwnd_cnt = 0;
+       tp->snd_cwnd_stamp = tcp_jiffies32;
+       tp->snd_ssthresh = tcp_current_ssthresh(sk);