From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall 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 Signed-off-by: Stafford Horne --- drivers/net/wireguard/cookie.h | 59 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 drivers/net/wireguard/cookie.h (limited to 'drivers/net/wireguard/cookie.h') diff --git a/drivers/net/wireguard/cookie.h b/drivers/net/wireguard/cookie.h new file mode 100644 index 000000000..c4bd61ca0 --- /dev/null +++ b/drivers/net/wireguard/cookie.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. + */ + +#ifndef _WG_COOKIE_H +#define _WG_COOKIE_H + +#include "messages.h" +#include + +struct wg_peer; + +struct cookie_checker { + u8 secret[NOISE_HASH_LEN]; + u8 cookie_encryption_key[NOISE_SYMMETRIC_KEY_LEN]; + u8 message_mac1_key[NOISE_SYMMETRIC_KEY_LEN]; + u64 secret_birthdate; + struct rw_semaphore secret_lock; + struct wg_device *device; +}; + +struct cookie { + u64 birthdate; + bool is_valid; + u8 cookie[COOKIE_LEN]; + bool have_sent_mac1; + u8 last_mac1_sent[COOKIE_LEN]; + u8 cookie_decryption_key[NOISE_SYMMETRIC_KEY_LEN]; + u8 message_mac1_key[NOISE_SYMMETRIC_KEY_LEN]; + struct rw_semaphore lock; +}; + +enum cookie_mac_state { + INVALID_MAC, + VALID_MAC_BUT_NO_COOKIE, + VALID_MAC_WITH_COOKIE_BUT_RATELIMITED, + VALID_MAC_WITH_COOKIE +}; + +void wg_cookie_checker_init(struct cookie_checker *checker, + struct wg_device *wg); +void wg_cookie_checker_precompute_device_keys(struct cookie_checker *checker); +void wg_cookie_checker_precompute_peer_keys(struct wg_peer *peer); +void wg_cookie_init(struct cookie *cookie); + +enum cookie_mac_state wg_cookie_validate_packet(struct cookie_checker *checker, + struct sk_buff *skb, + bool check_cookie); +void wg_cookie_add_mac_to_packet(void *message, size_t len, + struct wg_peer *peer); + +void wg_cookie_message_create(struct message_handshake_cookie *src, + struct sk_buff *skb, __le32 index, + struct cookie_checker *checker); +void wg_cookie_message_consume(struct message_handshake_cookie *src, + struct wg_device *wg); + +#endif /* _WG_COOKIE_H */ -- cgit v1.3.1