This is a note to let you know that I've just added the patch titled
net/tls: Fix sk_psock refcnt leak in bpf_exec_tx_verdict()
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-tls-fix-sk_psock-refcnt-leak-in-bpf_exec_tx_verdict.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue 12 May 2020 10:55:24 AM CEST
From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Date: Sat, 25 Apr 2020 20:54:37 +0800
Subject: net/tls: Fix sk_psock refcnt leak in bpf_exec_tx_verdict()
From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
[ Upstream commit 095f5614bfe16e5b3e191b34ea41b10d6fdd4ced ]
bpf_exec_tx_verdict() invokes sk_psock_get(), which returns a reference
of the specified sk_psock object to "psock" with increased refcnt.
When bpf_exec_tx_verdict() returns, local variable "psock" becomes
invalid, so the refcount should be decreased to keep refcount balanced.
The reference counting issue happens in one exception handling path of
bpf_exec_tx_verdict(). When "policy" equals to NULL but "psock" is not
NULL, the function forgets to decrease the refcnt increased by
sk_psock_get(), causing a refcnt leak.
Fix this issue by calling sk_psock_put() on this error path before
bpf_exec_tx_verdict() returns.
Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tls/tls_sw.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -797,6 +797,8 @@ static int bpf_exec_tx_verdict(struct sk
*copied -= sk_msg_free(sk, msg);
tls_free_open_rec(sk);
}
+ if (psock)
+ sk_psock_put(sk, psock);
return err;
}
more_data:
Patches currently in stable-queue which might be from xiyuyang19@xxxxxxxxxxxx are
queue-5.4/net-tls-fix-sk_psock-refcnt-leak-in-bpf_exec_tx_verdict.patch
queue-5.4/net-tls-fix-sk_psock-refcnt-leak-when-in-tls_data_ready.patch
