[PATCH AUTOSEL 4.9 02/36] e1000e: allow non-monotonic SYSTIM readings

[PATCH AUTOSEL 4.9 02/36] e1000e: allow non-monotonic SYSTIM readings

[Sasha Levin]

From: Miroslav Lichvar <mlichvar@redhat.com>

[ Upstream commit e1f65b0d70e9e5c80e15105cd96fa00174d7c436 ]

It seems with some NICs supported by the e1000e driver a SYSTIM reading
may occasionally be few microseconds before the previous reading and if
enabled also pass e1000e_sanitize_systim() without reaching the maximum
number of rereads, even if the function is modified to check three
consecutive readings (i.e. it doesn't look like a double read error).
This causes an underflow in the timecounter and the PHC time jumps hours
ahead.

This was observed on 82574, I217 and I219. The fastest way to reproduce
it is to run a program that continuously calls the PTP_SYS_OFFSET ioctl
on the PHC.

Modify e1000e_phc_gettime() to use timecounter_cyc2time() instead of
timecounter_read() in order to allow non-monotonic SYSTIM readings and
prevent the PHC from jumping.

Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Acked-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/e1000e/ptp.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000e/ptp.c b/drivers/net/ethernet/intel/e1000e/ptp.c
index ad03763e009a..a9f8edc17827 100644
--- a/drivers/net/ethernet/intel/e1000e/ptp.c
+++ b/drivers/net/ethernet/intel/e1000e/ptp.c
@@ -191,10 +191,14 @@ static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 						     ptp_clock_info);
 	unsigned long flags;
-	u64 ns;
+	u64 cycles, ns;
 
 	spin_lock_irqsave(&adapter->systim_lock, flags);
-	ns = timecounter_read(&adapter->tc);
+
+	/* Use timecounter_cyc2time() to allow non-monotonic SYSTIM readings */
+	cycles = adapter->cc.read(&adapter->cc);
+	ns = timecounter_cyc2time(&adapter->tc, cycles);
+
 	spin_unlock_irqrestore(&adapter->systim_lock, flags);
 
 	*ts = ns_to_timespec64(ns);
@@ -250,9 +254,12 @@ static void e1000e_systim_overflow_work(struct work_struct *work)
 						     systim_overflow_work.work);
 	struct e1000_hw *hw = &adapter->hw;
 	struct timespec64 ts;
+	u64 ns;
 
-	adapter->ptp_clock_info.gettime64(&adapter->ptp_clock_info, &ts);
+	/* Update the timecounter */
+	ns = timecounter_read(&adapter->tc);
 
+	ts = ns_to_timespec64(ns);
 	e_dbg("SYSTIM overflow check at %lld.%09lu\n",
 	      (long long) ts.tv_sec, ts.tv_nsec);
 
-- 
2.19.1

[PATCH AUTOSEL 4.9 17/36] net: call sk_dst_reset when set SO_DONTROUTE

[Sasha Levin]

From: yupeng <yupeng0921@gmail.com>

[ Upstream commit 0fbe82e628c817e292ff588cd5847fc935e025f2 ]

after set SO_DONTROUTE to 1, the IP layer should not route packets if
the dest IP address is not in link scope. But if the socket has cached
the dst_entry, such packets would be routed until the sk_dst_cache
expires. So we should clean the sk_dst_cache when a user set
SO_DONTROUTE option. Below are server/client python scripts which
could reprodue this issue:

server side code:

==========================================================================
import socket
import struct
import time

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('0.0.0.0', 9000))
s.listen(1)
sock, addr = s.accept()
sock.setsockopt(socket.SOL_SOCKET, socket.SO_DONTROUTE, struct.pack('i', 1))
while True:
    sock.send(b'foo')
    time.sleep(1)
==========================================================================

client side code:
==========================================================================
import socket
import time

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('server_address', 9000))
while True:
    data = s.recv(1024)
    print(data)
==========================================================================

Signed-off-by: yupeng <yupeng0921@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/sock.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/core/sock.c b/net/core/sock.c
index 1c4c43483b54..8566da877ec2 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -699,6 +699,7 @@ int sock_setsockopt(struct socket *sock, int level, int optname,
 		break;
 	case SO_DONTROUTE:
 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
+		sk_dst_reset(sk);
 		break;
 	case SO_BROADCAST:
 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
-- 
2.19.1