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/allowedips.h | 63 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 drivers/net/wireguard/allowedips.h (limited to 'drivers/net/wireguard/allowedips.h') diff --git a/drivers/net/wireguard/allowedips.h b/drivers/net/wireguard/allowedips.h new file mode 100644 index 000000000..931958cb6 --- /dev/null +++ b/drivers/net/wireguard/allowedips.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. + */ + +#ifndef _WG_ALLOWEDIPS_H +#define _WG_ALLOWEDIPS_H + +#include +#include +#include + +struct wg_peer; + +struct allowedips_node { + struct wg_peer __rcu *peer; + struct allowedips_node __rcu *bit[2]; + u8 cidr, bit_at_a, bit_at_b, bitlen; + u8 bits[16] __aligned(__alignof(u64)); + + /* Keep rarely used members at bottom to be beyond cache line. */ + unsigned long parent_bit_packed; + union { + struct list_head peer_list; + struct rcu_head rcu; + }; +}; + +struct allowedips { + struct allowedips_node __rcu *root4; + struct allowedips_node __rcu *root6; + u64 seq; +} __aligned(4); /* We pack the lower 2 bits of &root, but m68k only gives 16-bit alignment. */ + +void wg_allowedips_init(struct allowedips *table); +void wg_allowedips_free(struct allowedips *table, struct mutex *mutex); +int wg_allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip, + u8 cidr, struct wg_peer *peer, struct mutex *lock); +int wg_allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip, + u8 cidr, struct wg_peer *peer, struct mutex *lock); +int wg_allowedips_remove_v4(struct allowedips *table, const struct in_addr *ip, + u8 cidr, struct wg_peer *peer, struct mutex *lock); +int wg_allowedips_remove_v6(struct allowedips *table, const struct in6_addr *ip, + u8 cidr, struct wg_peer *peer, struct mutex *lock); +void wg_allowedips_remove_by_peer(struct allowedips *table, + struct wg_peer *peer, struct mutex *lock); +/* The ip input pointer should be __aligned(__alignof(u64))) */ +int wg_allowedips_read_node(struct allowedips_node *node, u8 ip[16], u8 *cidr); + +/* These return a strong reference to a peer: */ +struct wg_peer *wg_allowedips_lookup_dst(struct allowedips *table, + struct sk_buff *skb); +struct wg_peer *wg_allowedips_lookup_src(struct allowedips *table, + struct sk_buff *skb); + +#ifdef DEBUG +bool wg_allowedips_selftest(void); +#endif + +int wg_allowedips_slab_init(void); +void wg_allowedips_slab_uninit(void); + +#endif /* _WG_ALLOWEDIPS_H */ -- cgit v1.3.1