[PATCH AUTOSEL 4.19 1/5] drm/amd/display: clear optc underflow before turn off odm clock

[PATCH AUTOSEL 4.19 1/5] drm/amd/display: clear optc underflow before turn off odm clock

[Sasha Levin]

From: Fudong Wang <Fudong.Wang@amd.com>

[ Upstream commit b2a93490201300a749ad261b5c5d05cb50179c44 ]

[Why]
After ODM clock off, optc underflow bit will be kept there always and clear not work.
We need to clear that before clock off.

[How]
Clear that if have when clock off.

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Fudong Wang <Fudong.Wang@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
index 411f89218e01..cb5c44b339e0 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
@@ -452,6 +452,11 @@ void optc1_enable_optc_clock(struct timing_generator *optc, bool enable)
 				OTG_CLOCK_ON, 1,
 				1, 1000);
 	} else  {
+
+		//last chance to clear underflow, otherwise, it will always there due to clock is off.
+		if (optc->funcs->is_optc_underflow_occurred(optc) == true)
+			optc->funcs->clear_optc_underflow(optc);
+
 		REG_UPDATE_2(OTG_CLOCK_CONTROL,
 				OTG_CLOCK_GATE_DIS, 0,
 				OTG_CLOCK_EN, 0);
-- 
2.35.1

[PATCH AUTOSEL 4.19 2/5] neigh: fix possible DoS due to net iface start/stop loop

[Sasha Levin]

From: "Denis V. Lunev" <den@openvz.org>

[ Upstream commit 66ba215cb51323e4e55e38fd5f250e0fae0cbc94 ]

Normal processing of ARP request (usually this is Ethernet broadcast
packet) coming to the host is looking like the following:
* the packet comes to arp_process() call and is passed through routing
  procedure
* the request is put into the queue using pneigh_enqueue() if
  corresponding ARP record is not local (common case for container
  records on the host)
* the request is processed by timer (within 80 jiffies by default) and
  ARP reply is sent from the same arp_process() using
  NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED condition (flag is set inside
  pneigh_enqueue())

And here the problem comes. Linux kernel calls pneigh_queue_purge()
which destroys the whole queue of ARP requests on ANY network interface
start/stop event through __neigh_ifdown().

This is actually not a problem within the original world as network
interface start/stop was accessible to the host 'root' only, which
could do more destructive things. But the world is changed and there
are Linux containers available. Here container 'root' has an access
to this API and could be considered as untrusted user in the hosting
(container's) world.

Thus there is an attack vector to other containers on node when
container's root will endlessly start/stop interfaces. We have observed
similar situation on a real production node when docker container was
doing such activity and thus other containers on the node become not
accessible.

The patch proposed doing very simple thing. It drops only packets from
the same namespace in the pneigh_queue_purge() where network interface
state change is detected. This is enough to prevent the problem for the
whole node preserving original semantics of the code.

v2:
	- do del_timer_sync() if queue is empty after pneigh_queue_purge()
v3:
	- rebase to net tree

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@kernel.org>
Cc: Yajun Deng <yajun.deng@linux.dev>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>
Cc: Konstantin Khorenko <khorenko@virtuozzo.com>
Cc: kernel@openvz.org
Cc: devel@openvz.org
Investigated-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/neighbour.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 6233e9856016..65e80aaa0948 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -224,14 +224,23 @@ static int neigh_del_timer(struct neighbour *n)
 	return 0;
 }
 
-static void pneigh_queue_purge(struct sk_buff_head *list)
+static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net)
 {
+	unsigned long flags;
 	struct sk_buff *skb;
 
-	while ((skb = skb_dequeue(list)) != NULL) {
-		dev_put(skb->dev);
-		kfree_skb(skb);
+	spin_lock_irqsave(&list->lock, flags);
+	skb = skb_peek(list);
+	while (skb != NULL) {
+		struct sk_buff *skb_next = skb_peek_next(skb, list);
+		if (net == NULL || net_eq(dev_net(skb->dev), net)) {
+			__skb_unlink(skb, list);
+			dev_put(skb->dev);
+			kfree_skb(skb);
+		}
+		skb = skb_next;
 	}
+	spin_unlock_irqrestore(&list->lock, flags);
 }
 
 static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
@@ -297,9 +306,9 @@ int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 	write_lock_bh(&tbl->lock);
 	neigh_flush_dev(tbl, dev);
 	pneigh_ifdown_and_unlock(tbl, dev);
-
-	del_timer_sync(&tbl->proxy_timer);
-	pneigh_queue_purge(&tbl->proxy_queue);
+	pneigh_queue_purge(&tbl->proxy_queue, dev_net(dev));
+	if (skb_queue_empty_lockless(&tbl->proxy_queue))
+		del_timer_sync(&tbl->proxy_timer);
 	return 0;
 }
 EXPORT_SYMBOL(neigh_ifdown);
@@ -1614,7 +1623,7 @@ int neigh_table_clear(int index, struct neigh_table *tbl)
 	/* It is not clean... Fix it to unload IPv6 module safely */
 	cancel_delayed_work_sync(&tbl->gc_work);
 	del_timer_sync(&tbl->proxy_timer);
-	pneigh_queue_purge(&tbl->proxy_queue);
+	pneigh_queue_purge(&tbl->proxy_queue, NULL);
 	neigh_ifdown(tbl, NULL);
 	if (atomic_read(&tbl->entries))
 		pr_crit("neighbour leakage\n");
-- 
2.35.1

[PATCH AUTOSEL 4.19 3/5] s390/hypfs: avoid error message under KVM

[Sasha Levin]

From: Juergen Gross <jgross@suse.com>

[ Upstream commit 7b6670b03641ac308aaa6fa2e6f964ac993b5ea3 ]

When booting under KVM the following error messages are issued:

hypfs.7f5705: The hardware system does not support hypfs
hypfs.7a79f0: Initialization of hypfs failed with rc=-61

Demote the severity of first message from "error" to "info" and issue
the second message only in other error cases.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20220620094534.18967-1-jgross@suse.com
[arch/s390/hypfs/hypfs_diag.c changed description]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/hypfs/hypfs_diag.c | 2 +-
 arch/s390/hypfs/inode.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/s390/hypfs/hypfs_diag.c b/arch/s390/hypfs/hypfs_diag.c
index 3452e18bb1ca..38105ba35c81 100644
--- a/arch/s390/hypfs/hypfs_diag.c
+++ b/arch/s390/hypfs/hypfs_diag.c
@@ -437,7 +437,7 @@ __init int hypfs_diag_init(void)
 	int rc;
 
 	if (diag204_probe()) {
-		pr_err("The hardware system does not support hypfs\n");
+		pr_info("The hardware system does not support hypfs\n");
 		return -ENODATA;
 	}
 	if (diag204_info_type == DIAG204_INFO_EXT) {
diff --git a/arch/s390/hypfs/inode.c b/arch/s390/hypfs/inode.c
index e4d17d9ea93d..4af5c0dd9fbe 100644
--- a/arch/s390/hypfs/inode.c
+++ b/arch/s390/hypfs/inode.c
@@ -494,9 +494,9 @@ static int __init hypfs_init(void)
 	hypfs_vm_exit();
 fail_hypfs_diag_exit:
 	hypfs_diag_exit();
+	pr_err("Initialization of hypfs failed with rc=%i\n", rc);
 fail_dbfs_exit:
 	hypfs_dbfs_exit();
-	pr_err("Initialization of hypfs failed with rc=%i\n", rc);
 	return rc;
 }
 device_initcall(hypfs_init)
-- 
2.35.1

[PATCH AUTOSEL 4.19 4/5] netfilter: conntrack: NF_CONNTRACK_PROCFS should no longer default to y

[Sasha Levin]

From: Geert Uytterhoeven <geert@linux-m68k.org>

[ Upstream commit aa5762c34213aba7a72dc58e70601370805fa794 ]

NF_CONNTRACK_PROCFS was marked obsolete in commit 54b07dca68557b09
("netfilter: provide config option to disable ancient procfs parts") in
v3.3.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 56cddadb65d0..92e0514f624f 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -117,7 +117,6 @@ config NF_CONNTRACK_ZONES
 
 config NF_CONNTRACK_PROCFS
 	bool "Supply CT list in procfs (OBSOLETE)"
-	default y
 	depends on PROC_FS
 	---help---
 	This option enables for the list of known conntrack entries
-- 
2.35.1

[PATCH AUTOSEL 4.19 5/5] ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead

[Sasha Levin]

From: Yang Jihong <yangjihong1@huawei.com>

[ Upstream commit c3b0f72e805f0801f05fa2aa52011c4bfc694c44 ]

ftrace_startup does not remove ops from ftrace_ops_list when
ftrace_startup_enable fails:

register_ftrace_function
  ftrace_startup
    __register_ftrace_function
      ...
      add_ftrace_ops(&ftrace_ops_list, ops)
      ...
    ...
    ftrace_startup_enable // if ftrace failed to modify, ftrace_disabled is set to 1
    ...
  return 0 // ops is in the ftrace_ops_list.

When ftrace_disabled = 1, unregister_ftrace_function simply returns without doing anything:
unregister_ftrace_function
  ftrace_shutdown
    if (unlikely(ftrace_disabled))
            return -ENODEV;  // return here, __unregister_ftrace_function is not executed,
                             // as a result, ops is still in the ftrace_ops_list
    __unregister_ftrace_function
    ...

If ops is dynamically allocated, it will be free later, in this case,
is_ftrace_trampoline accesses NULL pointer:

is_ftrace_trampoline
  ftrace_ops_trampoline
    do_for_each_ftrace_op(op, ftrace_ops_list) // OOPS! op may be NULL!

Syzkaller reports as follows:
[ 1203.506103] BUG: kernel NULL pointer dereference, address: 000000000000010b
[ 1203.508039] #PF: supervisor read access in kernel mode
[ 1203.508798] #PF: error_code(0x0000) - not-present page
[ 1203.509558] PGD 800000011660b067 P4D 800000011660b067 PUD 130fb8067 PMD 0
[ 1203.510560] Oops: 0000 [#1] SMP KASAN PTI
[ 1203.511189] CPU: 6 PID: 29532 Comm: syz-executor.2 Tainted: G    B   W         5.10.0 #8
[ 1203.512324] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 1203.513895] RIP: 0010:is_ftrace_trampoline+0x26/0xb0
[ 1203.514644] Code: ff eb d3 90 41 55 41 54 49 89 fc 55 53 e8 f2 00 fd ff 48 8b 1d 3b 35 5d 03 e8 e6 00 fd ff 48 8d bb 90 00 00 00 e8 2a 81 26 00 <48> 8b ab 90 00 00 00 48 85 ed 74 1d e8 c9 00 fd ff 48 8d bb 98 00
[ 1203.518838] RSP: 0018:ffffc900012cf960 EFLAGS: 00010246
[ 1203.520092] RAX: 0000000000000000 RBX: 000000000000007b RCX: ffffffff8a331866
[ 1203.521469] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000000010b
[ 1203.522583] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8df18b07
[ 1203.523550] R10: fffffbfff1be3160 R11: 0000000000000001 R12: 0000000000478399
[ 1203.524596] R13: 0000000000000000 R14: ffff888145088000 R15: 0000000000000008
[ 1203.525634] FS:  00007f429f5f4700(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000
[ 1203.526801] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1203.527626] CR2: 000000000000010b CR3: 0000000170e1e001 CR4: 00000000003706e0
[ 1203.528611] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1203.529605] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Therefore, when ftrace_startup_enable fails, we need to rollback registration
process and remove ops from ftrace_ops_list.

Link: https://lkml.kernel.org/r/20220818032659.56209-1-yangjihong1@huawei.com

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/trace/ftrace.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 998d141488a9..d2272fff2f59 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2748,6 +2748,16 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
 
 	ftrace_startup_enable(command);
 
+	/*
+	 * If ftrace is in an undefined state, we just remove ops from list
+	 * to prevent the NULL pointer, instead of totally rolling it back and
+	 * free trampoline, because those actions could cause further damage.
+	 */
+	if (unlikely(ftrace_disabled)) {
+		__unregister_ftrace_function(ops);
+		return -ENODEV;
+	}
+
 	ops->flags &= ~FTRACE_OPS_FL_ADDING;
 
 	return 0;
-- 
2.35.1