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 --- include/net/fq.h | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 include/net/fq.h (limited to 'include/net/fq.h') diff --git a/include/net/fq.h b/include/net/fq.h new file mode 100644 index 000000000..99fbe4127 --- /dev/null +++ b/include/net/fq.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2016 Qualcomm Atheros, Inc + * + * Based on net/sched/sch_fq_codel.c + */ +#ifndef __NET_SCHED_FQ_H +#define __NET_SCHED_FQ_H + +#include +#include +#include + +struct fq_tin; + +/** + * struct fq_flow - per traffic flow queue + * + * @tin: owner of this flow. Used to manage collisions, i.e. when a packet + * hashes to an index which points to a flow that is already owned by a + * different tin the packet is destined to. In such case the implementer + * must provide a fallback flow + * @flowchain: can be linked to fq_tin's new_flows or old_flows. Used for DRR++ + * (deficit round robin) based round robin queuing similar to the one + * found in net/sched/sch_fq_codel.c + * @queue: sk_buff queue to hold packets + * @backlog: number of bytes pending in the queue. The number of packets can be + * found in @queue.qlen + * @deficit: used for DRR++ + */ +struct fq_flow { + struct fq_tin *tin; + struct list_head flowchain; + struct sk_buff_head queue; + u32 backlog; + int deficit; +}; + +/** + * struct fq_tin - a logical container of fq_flows + * + * Used to group fq_flows into a logical aggregate. DRR++ scheme is used to + * pull interleaved packets out of the associated flows. + * + * @new_flows: linked list of fq_flow + * @old_flows: linked list of fq_flow + */ +struct fq_tin { + struct list_head new_flows; + struct list_head old_flows; + struct list_head tin_list; + struct fq_flow default_flow; + u32 backlog_bytes; + u32 backlog_packets; + u32 overlimit; + u32 collisions; + u32 flows; + u32 tx_bytes; + u32 tx_packets; +}; + +/** + * struct fq - main container for fair queuing purposes + * + * @limit: max number of packets that can be queued across all flows + * @backlog: number of packets queued across all flows + */ +struct fq { + struct fq_flow *flows; + unsigned long *flows_bitmap; + + struct list_head tin_backlog; + spinlock_t lock; + u32 flows_cnt; + u32 limit; + u32 memory_limit; + u32 memory_usage; + u32 quantum; + u32 backlog; + u32 overlimit; + u32 overmemory; + u32 collisions; +}; + +typedef struct sk_buff *fq_tin_dequeue_t(struct fq *, + struct fq_tin *, + struct fq_flow *flow); + +typedef void fq_skb_free_t(struct fq *, + struct fq_tin *, + struct fq_flow *, + struct sk_buff *); + +/* Return %true to filter (drop) the frame. */ +typedef bool fq_skb_filter_t(struct fq *, + struct fq_tin *, + struct fq_flow *, + struct sk_buff *, + void *); + +#endif -- cgit v1.3.1