This is a note to let you know that I've just added the patch titled
nfc: Avoid endless loops caused by repeated llcp_sock_connect()
to the 4.19-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:
nfc-avoid-endless-loops-caused-by-repeated-llcp_sock_connect.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4b5db93e7f2afbdfe3b78e37879a85290187e6f1 Mon Sep 17 00:00:00 2001
From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Date: Thu, 25 Mar 2021 11:51:13 +0800
Subject: nfc: Avoid endless loops caused by repeated llcp_sock_connect()
MIME-Version: 1.0
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From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
commit 4b5db93e7f2afbdfe3b78e37879a85290187e6f1 upstream.
When sock_wait_state() returns -EINPROGRESS, "sk->sk_state" is
LLCP_CONNECTING. In this case, llcp_sock_connect() is repeatedly invoked,
nfc_llcp_sock_link() will add sk to local->connecting_sockets twice.
sk->sk_node->next will point to itself, that will make an endless loop
and hang-up the system.
To fix it, check whether sk->sk_state is LLCP_CONNECTING in
llcp_sock_connect() to avoid repeated invoking.
Fixes: b4011239a08e ("NFC: llcp: Fix non blocking sockets connections")
Reported-by: "kiyin(尹亮)" <kiyin@xxxxxxxxxxx>
Link: https://www.openwall.com/lists/oss-security/2020/11/01/1
Cc: <stable@xxxxxxxxxxxxxxx> #v3.11
Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/nfc/llcp_sock.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -685,6 +685,10 @@ static int llcp_sock_connect(struct sock
ret = -EISCONN;
goto error;
}
+ if (sk->sk_state == LLCP_CONNECTING) {
+ ret = -EINPROGRESS;
+ goto error;
+ }
dev = nfc_get_device(addr->dev_idx);
if (dev == NULL) {
Patches currently in stable-queue which might be from nixiaoming@xxxxxxxxxx are
queue-4.19/nfc-avoid-endless-loops-caused-by-repeated-llcp_sock_connect.patch
queue-4.19/nfc-fix-memory-leak-in-llcp_sock_connect.patch
queue-4.19/nfc-fix-refcount-leak-in-llcp_sock_bind.patch
queue-4.19/nfc-fix-refcount-leak-in-llcp_sock_connect.patch
