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 --- net/openvswitch/meter.h | 62 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 net/openvswitch/meter.h (limited to 'net/openvswitch/meter.h') diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h new file mode 100644 index 000000000..8bbf983cd --- /dev/null +++ b/net/openvswitch/meter.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2017 Nicira, Inc. + */ + +#ifndef METER_H +#define METER_H 1 + +#include +#include +#include +#include +#include +#include +#include + +#include "flow.h" +struct datapath; + +#define DP_MAX_BANDS 1 +#define DP_METER_ARRAY_SIZE_MIN BIT_ULL(10) +#define DP_METER_NUM_MAX (200000UL) + +struct dp_meter_band { + u32 type; + u32 rate; + u32 burst_size; + u64 bucket; /* 1/1000 packets, or in bits */ + struct ovs_flow_stats stats; +}; + +struct dp_meter { + spinlock_t lock; /* Per meter lock */ + struct rcu_head rcu; + u32 id; + u16 kbps:1, keep_stats:1; + u16 n_bands; + u32 max_delta_t; + u64 used; + struct ovs_flow_stats stats; + struct dp_meter_band bands[] __counted_by(n_bands); +}; + +struct dp_meter_instance { + struct rcu_head rcu; + u32 n_meters; + struct dp_meter __rcu *dp_meters[] __counted_by(n_meters); +}; + +struct dp_meter_table { + struct dp_meter_instance __rcu *ti; + u32 count; + u32 max_meters_allowed; +}; + +extern struct genl_family dp_meter_genl_family; +int ovs_meters_init(struct datapath *dp); +void ovs_meters_exit(struct datapath *dp); +bool ovs_meter_execute(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, u32 meter_id); + +#endif /* meter.h */ -- cgit v1.3.1