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/smc/smc_sysctl.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 net/smc/smc_sysctl.h (limited to 'net/smc/smc_sysctl.h') diff --git a/net/smc/smc_sysctl.h b/net/smc/smc_sysctl.h new file mode 100644 index 000000000..8538915af --- /dev/null +++ b/net/smc/smc_sysctl.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * smc_sysctl.c: sysctl interface to SMC subsystem. + * + * Copyright (c) 2022, Alibaba Inc. + * + * Author: Tony Lu + * + */ + +#ifndef _SMC_SYSCTL_H +#define _SMC_SYSCTL_H + +#ifdef CONFIG_SYSCTL + +int __net_init smc_sysctl_net_init(struct net *net); +void __net_exit smc_sysctl_net_exit(struct net *net); + +#else + +static inline int smc_sysctl_net_init(struct net *net) +{ + net->smc.sysctl_autocorking_size = SMC_AUTOCORKING_DEFAULT_SIZE; + net->smc.sysctl_max_links_per_lgr = SMC_LINKS_PER_LGR_MAX_PREFER; + net->smc.sysctl_max_conns_per_lgr = SMC_CONN_PER_LGR_PREFER; + net->smc.sysctl_smcr_max_send_wr = SMCR_MAX_SEND_WR_DEF; + net->smc.sysctl_smcr_max_recv_wr = SMCR_MAX_RECV_WR_DEF; + return 0; +} + +static inline void smc_sysctl_net_exit(struct net *net) { } + +#endif /* CONFIG_SYSCTL */ + +#endif /* _SMC_SYSCTL_H */ -- cgit v1.3.1