openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted

sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.

    l.lwz   r29,0(r4)
    l.lwz   r27,0(r5)
    l.sw    0(r4),r27
    l.sw    0(r5),r29

The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.

A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.

This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.

Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.

[shorne@gmail.com: fix comment style]
Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>

1 files changed, 75 insertions, 0 deletions

diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
new file mode 100644
index 000000000..20810cf06
--- /dev/null
+++ b/net/bluetooth/mgmt_util.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+   BlueZ - Bluetooth protocol stack for Linux
+   Copyright (C) 2015  Intel Coropration
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
+   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
+   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
+   SOFTWARE IS DISCLAIMED.
+*/
+
+struct mgmt_mesh_tx {
+	struct list_head list;
+	int index;
+	size_t param_len;
+	struct sock *sk;
+	u8 handle;
+	u8 instance;
+	u8 param[sizeof(struct mgmt_cp_mesh_send) + 31];
+};
+
+struct mgmt_pending_cmd {
+	struct list_head list;
+	u16 opcode;
+	struct hci_dev *hdev;
+	void *param;
+	size_t param_len;
+	struct sock *sk;
+	struct sk_buff *skb;
+	void *user_data;
+	int (*cmd_complete)(struct mgmt_pending_cmd *cmd, u8 status);
+};
+
+struct sk_buff *mgmt_alloc_skb(struct hci_dev *hdev, u16 opcode,
+			       unsigned int size);
+int mgmt_send_event_skb(unsigned short channel, struct sk_buff *skb, int flag,
+			struct sock *skip_sk);
+int mgmt_send_event(u16 event, struct hci_dev *hdev, unsigned short channel,
+		    void *data, u16 data_len, int flag, struct sock *skip_sk);
+int mgmt_cmd_status(struct sock *sk, u16 index, u16 cmd, u8 status);
+int mgmt_cmd_complete(struct sock *sk, u16 index, u16 cmd, u8 status,
+		      void *rp, size_t rp_len);
+
+struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
+					   struct hci_dev *hdev);
+void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev, bool remove,
+			  void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
+			  void *data);
+struct mgmt_pending_cmd *mgmt_pending_add(struct sock *sk, u16 opcode,
+					  struct hci_dev *hdev,
+					  void *data, u16 len);
+struct mgmt_pending_cmd *mgmt_pending_new(struct sock *sk, u16 opcode,
+					  struct hci_dev *hdev,
+					  void *data, u16 len);
+void mgmt_pending_free(struct mgmt_pending_cmd *cmd);
+void mgmt_pending_remove(struct mgmt_pending_cmd *cmd);
+bool __mgmt_pending_listed(struct hci_dev *hdev, struct mgmt_pending_cmd *cmd);
+bool mgmt_pending_listed(struct hci_dev *hdev, struct mgmt_pending_cmd *cmd);
+bool mgmt_pending_valid(struct hci_dev *hdev, struct mgmt_pending_cmd *cmd);
+void mgmt_mesh_foreach(struct hci_dev *hdev,
+		       void (*cb)(struct mgmt_mesh_tx *mesh_tx, void *data),
+		       void *data, struct sock *sk);
+struct mgmt_mesh_tx *mgmt_mesh_find(struct hci_dev *hdev, u8 handle);
+struct mgmt_mesh_tx *mgmt_mesh_next(struct hci_dev *hdev, struct sock *sk);
+struct mgmt_mesh_tx *mgmt_mesh_add(struct sock *sk, struct hci_dev *hdev,
+				   void *data, u16 len);
+void mgmt_mesh_remove(struct mgmt_mesh_tx *mesh_tx);