[PATCH net 1/2] tipc: error path leak fixes in tipc_enable_bearer()

Fix memory leak in tipc_enable_bearer() if enable_media() fails, and
cleanup with bearer_disable() if tipc_mon_create() fails.

Acked-by: Ying Xue <redacted>
Acked-by: Jon Maloy <redacted>
Signed-off-by: Tommi Rantala <redacted>
---
 net/tipc/bearer.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 47ec121574ce..c8001471da6c 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c

@@ -324,6 +324,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	if (res) {
 		pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
 			name, -res);
+		kfree(b);
 		return -EINVAL;
 	}
 

@@ -347,8 +348,10 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	if (skb)
 		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
 
-	if (tipc_mon_create(net, bearer_id))
+	if (tipc_mon_create(net, bearer_id)) {
+		bearer_disable(net, b);
 		return -ENOMEM;
+	}
 
 	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
 		name,

-- 
2.14.3

Calling tipc_mon_delete() before the monitor has been created will oops.
This can happen in tipc_enable_bearer() error path if tipc_disc_create()
fails.

[   48.589074] BUG: unable to handle kernel paging request at 0000000000001008
[   48.590266] IP: tipc_mon_delete+0xea/0x270 [tipc]
[   48.591223] PGD 1e60c5067 P4D 1e60c5067 PUD 1eb0cf067 PMD 0
[   48.592230] Oops: 0000 [#1] SMP KASAN
[   48.595610] CPU: 5 PID: 1199 Comm: tipc Tainted: G    B            4.15.0-rc4-pc64-dirty #5
[   48.597176] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[   48.598489] RIP: 0010:tipc_mon_delete+0xea/0x270 [tipc]
[   48.599347] RSP: 0018:ffff8801d827f668 EFLAGS: 00010282
[   48.600705] RAX: ffff8801ee813f00 RBX: 0000000000000204 RCX: 0000000000000000
[   48.602183] RDX: 1ffffffff1de6a75 RSI: 0000000000000297 RDI: 0000000000000297
[   48.604373] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff1dd1533
[   48.605607] R10: ffffffff8eafbb05 R11: fffffbfff1dd1534 R12: 0000000000000050
[   48.607082] R13: dead000000000200 R14: ffffffff8e73f310 R15: 0000000000001020
[   48.608228] FS:  00007fc686484800(0000) GS:ffff8801f5540000(0000) knlGS:0000000000000000
[   48.610189] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   48.611459] CR2: 0000000000001008 CR3: 00000001dda70002 CR4: 00000000003606e0
[   48.612759] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   48.613831] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   48.615038] Call Trace:
[   48.615635]  tipc_enable_bearer+0x415/0x5e0 [tipc]
[   48.620623]  tipc_nl_bearer_enable+0x1ab/0x200 [tipc]
[   48.625118]  genl_family_rcv_msg+0x36b/0x570
[   48.631233]  genl_rcv_msg+0x5a/0xa0
[   48.631867]  netlink_rcv_skb+0x1cc/0x220
[   48.636373]  genl_rcv+0x24/0x40
[   48.637306]  netlink_unicast+0x29c/0x350
[   48.639664]  netlink_sendmsg+0x439/0x590
[   48.642014]  SYSC_sendto+0x199/0x250
[   48.649912]  do_syscall_64+0xfd/0x2c0
[   48.650651]  entry_SYSCALL64_slow_path+0x25/0x25
[   48.651843] RIP: 0033:0x7fc6859848e3
[   48.652539] RSP: 002b:00007ffd25dff938 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   48.654003] RAX: ffffffffffffffda RBX: 00007ffd25dff990 RCX: 00007fc6859848e3
[   48.655303] RDX: 0000000000000054 RSI: 00007ffd25dff990 RDI: 0000000000000003
[   48.656512] RBP: 00007ffd25dff980 R08: 00007fc685c35fc0 R09: 000000000000000c
[   48.657697] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000d13010
[   48.658840] R13: 00007ffd25e009c0 R14: 0000000000000000 R15: 0000000000000000
[   48.662972] RIP: tipc_mon_delete+0xea/0x270 [tipc] RSP: ffff8801d827f668
[   48.664073] CR2: 0000000000001008
[   48.664576] ---[ end trace e811818d54d5ce88 ]---

Acked-by: Ying Xue <redacted>
Acked-by: Jon Maloy <redacted>
Signed-off-by: Tommi Rantala <redacted>
---
 net/tipc/monitor.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/tipc/monitor.c b/net/tipc/monitor.c
index 8e884ed06d4b..32dc33a94bc7 100644
--- a/net/tipc/monitor.c
+++ b/net/tipc/monitor.c

@@ -642,9 +642,13 @@ void tipc_mon_delete(struct net *net, int bearer_id)
 {
 	struct tipc_net *tn = tipc_net(net);
 	struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
-	struct tipc_peer *self = get_self(net, bearer_id);
+	struct tipc_peer *self;
 	struct tipc_peer *peer, *tmp;
 
+	if (!mon)
+		return;
+
+	self = get_self(net, bearer_id);
 	write_lock_bh(&mon->lock);
 	tn->monitors[bearer_id] = NULL;
 	list_for_each_entry_safe(peer, tmp, &self->list, list) {

-- 
2.14.3


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From: Tommi Rantala <redacted>
Date: Fri, 22 Dec 2017 09:35:16 +0200

Fix memory leak in tipc_enable_bearer() if enable_media() fails, and
cleanup with bearer_disable() if tipc_mon_create() fails.

Acked-by: Ying Xue <redacted>
Acked-by: Jon Maloy <redacted>
Signed-off-by: Tommi Rantala <redacted>

Applied.

From: Tommi Rantala <redacted>
Date: Fri, 22 Dec 2017 09:35:17 +0200

Calling tipc_mon_delete() before the monitor has been created will oops.
This can happen in tipc_enable_bearer() error path if tipc_disc_create()
fails.

 ...

Acked-by: Ying Xue <redacted>
Acked-by: Jon Maloy <redacted>
Signed-off-by: Tommi Rantala <redacted>

Applied.