From: Sasha Levin <sashal@kernel.org>
Date: Thu, 29 Aug 2019 03:38:12 +0000 (-0400)
Subject: fixes for 4.19
X-Git-Tag: v4.14.141~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0c7efce02eb4f7db4c8ecc9944b85c6b28febfa9;p=thirdparty%2Fkernel%2Fstable-queue.git

fixes for 4.19

Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/queue-4.19/rxrpc-fix-local-refcounting.patch b/queue-4.19/rxrpc-fix-local-refcounting.patch
new file mode 100644
index 00000000000..fdadc6bab08
--- /dev/null
+++ b/queue-4.19/rxrpc-fix-local-refcounting.patch
@@ -0,0 +1,73 @@
+From ff320ff4fb793dbc818edab538f5e660259b0024 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 9 Aug 2019 22:47:47 +0100
+Subject: rxrpc: Fix local refcounting
+
+[ Upstream commit 68553f1a6f746bf860bce3eb42d78c26a717d9c0 ]
+
+Fix rxrpc_unuse_local() to handle a NULL local pointer as it can be called
+on an unbound socket on which rx->local is not yet set.
+
+The following reproduced (includes omitted):
+
+	int main(void)
+	{
+		socket(AF_RXRPC, SOCK_DGRAM, AF_INET);
+		return 0;
+	}
+
+causes the following oops to occur:
+
+	BUG: kernel NULL pointer dereference, address: 0000000000000010
+	...
+	RIP: 0010:rxrpc_unuse_local+0x8/0x1b
+	...
+	Call Trace:
+	 rxrpc_release+0x2b5/0x338
+	 __sock_release+0x37/0xa1
+	 sock_close+0x14/0x17
+	 __fput+0x115/0x1e9
+	 task_work_run+0x72/0x98
+	 do_exit+0x51b/0xa7a
+	 ? __context_tracking_exit+0x4e/0x10e
+	 do_group_exit+0xab/0xab
+	 __x64_sys_exit_group+0x14/0x17
+	 do_syscall_64+0x89/0x1d4
+	 entry_SYSCALL_64_after_hwframe+0x49/0xbe
+
+Reported-by: syzbot+20dee719a2e090427b5f@syzkaller.appspotmail.com
+Fixes: 730c5fd42c1e ("rxrpc: Fix local endpoint refcounting")
+Signed-off-by: David Howells <dhowells@redhat.com>
+cc: Jeffrey Altman <jaltman@auristor.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ net/rxrpc/local_object.c | 12 +++++++-----
+ 1 file changed, 7 insertions(+), 5 deletions(-)
+
+diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
+index 27f4bbe85e799..c752ad4870678 100644
+--- a/net/rxrpc/local_object.c
++++ b/net/rxrpc/local_object.c
+@@ -407,11 +407,13 @@ void rxrpc_unuse_local(struct rxrpc_local *local)
+ {
+ 	unsigned int au;
+ 
+-	au = atomic_dec_return(&local->active_users);
+-	if (au == 0)
+-		rxrpc_queue_local(local);
+-	else
+-		rxrpc_put_local(local);
++	if (local) {
++		au = atomic_dec_return(&local->active_users);
++		if (au == 0)
++			rxrpc_queue_local(local);
++		else
++			rxrpc_put_local(local);
++	}
+ }
+ 
+ /*
+-- 
+2.20.1
+
diff --git a/queue-4.19/series b/queue-4.19/series
index 2f60c4576cd..904bfca5a89 100644
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -97,3 +97,4 @@ powerpc-allow-flush_-inval_-dcache_range-to-work-across-ranges-4gb.patch
 rxrpc-fix-local-endpoint-refcounting.patch
 rxrpc-fix-read-after-free-in-rxrpc_queue_local.patch
 rxrpc-fix-local-endpoint-replacement.patch
+rxrpc-fix-local-refcounting.patch