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authorHyunwoo Kim <v4bel@theori.io>2023-12-09 11:55:18 +0100
committerLuiz Augusto von Dentz <luiz.von.dentz@intel.com>2023-12-15 17:54:18 +0100
commit2e07e8348ea454615e268222ae3fc240421be768 (patch)
tree2f11a56621670d5286765251725e03531e5fce08
parentBluetooth: Add more enc key size check (diff)
downloadlinux-2e07e8348ea454615e268222ae3fc240421be768.tar.xz
linux-2e07e8348ea454615e268222ae3fc240421be768.zip
Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg
This can cause a race with bt_sock_ioctl() because bt_sock_recvmsg() gets the skb from sk->sk_receive_queue and then frees it without holding lock_sock. A use-after-free for a skb occurs with the following flow. ``` bt_sock_recvmsg() -> skb_recv_datagram() -> skb_free_datagram() bt_sock_ioctl() -> skb_peek() ``` Add lock_sock to bt_sock_recvmsg() to fix this issue. Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim <v4bel@theori.io> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
-rw-r--r--net/bluetooth/af_bluetooth.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 336a76165454..b93464ac3517 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -309,11 +309,14 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
if (flags & MSG_OOB)
return -EOPNOTSUPP;
+ lock_sock(sk);
+
skb = skb_recv_datagram(sk, flags, &err);
if (!skb) {
if (sk->sk_shutdown & RCV_SHUTDOWN)
- return 0;
+ err = 0;
+ release_sock(sk);
return err;
}
@@ -343,6 +346,8 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
skb_free_datagram(sk, skb);
+ release_sock(sk);
+
if (flags & MSG_TRUNC)
copied = skblen;