4.4-stable patches

added patches:
	tipc-fix-use-after-free-in-tipc_bcast_get_mode.patch

diff --git a/queue-4.4/series b/queue-4.4/series
index 20372992d4c839ab8f94671cbc9671675d7c5735..7970c67d8994b8d49e25277436f45ad2ebd66225 100644 (file)
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -62,3 +62,4 @@ device-property-keep-secondary-firmware-node-secondary-by-type.patch
 device-property-don-t-clear-secondary-pointer-for-shared-primary-firmware-node.patch
 staging-comedi-cb_pcidas-allow-2-channel-commands-for-ao-subdevice.patch
 xen-events-don-t-use-chip_data-for-legacy-irqs.patch
+tipc-fix-use-after-free-in-tipc_bcast_get_mode.patch

diff --git a/queue-4.4/tipc-fix-use-after-free-in-tipc_bcast_get_mode.patch b/queue-4.4/tipc-fix-use-after-free-in-tipc_bcast_get_mode.patch
new file mode 100644 (file)
index 0000000..f88292d
--- /dev/null
+++ b/queue-4.4/tipc-fix-use-after-free-in-tipc_bcast_get_mode.patch
@@ -0,0 +1,101 @@
+From fdeba99b1e58ecd18c2940c453e19e4ef20ff591 Mon Sep 17 00:00:00 2001
+From: Hoang Huu Le <hoang.h.le@dektech.com.au>
+Date: Thu, 27 Aug 2020 09:56:51 +0700
+Subject: tipc: fix use-after-free in tipc_bcast_get_mode
+
+From: Hoang Huu Le <hoang.h.le@dektech.com.au>
+
+commit fdeba99b1e58ecd18c2940c453e19e4ef20ff591 upstream.
+
+Syzbot has reported those issues as:
+
+==================================================================
+BUG: KASAN: use-after-free in tipc_bcast_get_mode+0x3ab/0x400 net/tipc/bcast.c:759
+Read of size 1 at addr ffff88805e6b3571 by task kworker/0:6/3850
+
+CPU: 0 PID: 3850 Comm: kworker/0:6 Not tainted 5.8.0-rc7-syzkaller #0
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+Workqueue: events tipc_net_finalize_work
+
+Thread 1's call trace:
+[...]
+  kfree+0x103/0x2c0 mm/slab.c:3757 <- bcbase releasing
+  tipc_bcast_stop+0x1b0/0x2f0 net/tipc/bcast.c:721
+  tipc_exit_net+0x24/0x270 net/tipc/core.c:112
+[...]
+
+Thread 2's call trace:
+[...]
+  tipc_bcast_get_mode+0x3ab/0x400 net/tipc/bcast.c:759 <- bcbase
+has already been freed by Thread 1
+
+  tipc_node_broadcast+0x9e/0xcc0 net/tipc/node.c:1744
+  tipc_nametbl_publish+0x60b/0x970 net/tipc/name_table.c:752
+  tipc_net_finalize net/tipc/net.c:141 [inline]
+  tipc_net_finalize+0x1fa/0x310 net/tipc/net.c:131
+  tipc_net_finalize_work+0x55/0x80 net/tipc/net.c:150
+[...]
+
+==================================================================
+BUG: KASAN: use-after-free in tipc_named_reinit+0xef/0x290 net/tipc/name_distr.c:344
+Read of size 8 at addr ffff888052ab2000 by task kworker/0:13/30628
+CPU: 0 PID: 30628 Comm: kworker/0:13 Not tainted 5.8.0-syzkaller #0
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+Workqueue: events tipc_net_finalize_work
+Call Trace:
+ __dump_stack lib/dump_stack.c:77 [inline]
+ dump_stack+0x1f0/0x31e lib/dump_stack.c:118
+ print_address_description+0x66/0x5a0 mm/kasan/report.c:383
+ __kasan_report mm/kasan/report.c:513 [inline]
+ kasan_report+0x132/0x1d0 mm/kasan/report.c:530
+ tipc_named_reinit+0xef/0x290 net/tipc/name_distr.c:344
+ tipc_net_finalize+0x85/0xe0 net/tipc/net.c:138
+ tipc_net_finalize_work+0x50/0x70 net/tipc/net.c:150
+ process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
+ worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
+ kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
+ ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
+[...]
+Freed by task 14058:
+ save_stack mm/kasan/common.c:48 [inline]
+ set_track mm/kasan/common.c:56 [inline]
+ kasan_set_free_info mm/kasan/common.c:316 [inline]
+ __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455
+ __cache_free mm/slab.c:3426 [inline]
+ kfree+0x10a/0x220 mm/slab.c:3757
+ tipc_exit_net+0x29/0x50 net/tipc/core.c:113
+ ops_exit_list net/core/net_namespace.c:186 [inline]
+ cleanup_net+0x708/0xba0 net/core/net_namespace.c:603
+ process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
+ worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
+ kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
+ ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
+
+Fix it by calling flush_scheduled_work() to make sure the
+tipc_net_finalize_work() stopped before releasing bcbase object.
+
+Reported-by: syzbot+6ea1f7a8df64596ef4d7@syzkaller.appspotmail.com
+Reported-by: syzbot+e9cc557752ab126c1b99@syzkaller.appspotmail.com
+Acked-by: Jon Maloy <jmaloy@redhat.com>
+Signed-off-by: Hoang Huu Le <hoang.h.le@dektech.com.au>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ net/tipc/core.c |    5 +++++
+ 1 file changed, 5 insertions(+)
+
+--- a/net/tipc/core.c
++++ b/net/tipc/core.c
+@@ -88,6 +88,11 @@ out_sk_rht:
+ static void __net_exit tipc_exit_net(struct net *net)
+ {
+       tipc_net_stop(net);
++
++      /* Make sure the tipc_net_finalize_work stopped
++       * before releasing the resources.
++       */
++      flush_scheduled_work();
+       tipc_bcast_stop(net);
+       tipc_nametbl_stop(net);
+       tipc_sk_rht_destroy(net);