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/sunrpc/netlink.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 net/sunrpc/netlink.h (limited to 'net/sunrpc/netlink.h') diff --git a/net/sunrpc/netlink.h b/net/sunrpc/netlink.h new file mode 100644 index 000000000..2c1012303 --- /dev/null +++ b/net/sunrpc/netlink.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/sunrpc_cache.yaml */ +/* YNL-GEN kernel header */ +/* To regenerate run: tools/net/ynl/ynl-regen.sh */ + +#ifndef _LINUX_SUNRPC_GEN_H +#define _LINUX_SUNRPC_GEN_H + +#include +#include + +#include + +/* Common nested types */ +extern const struct nla_policy sunrpc_ip_map_nl_policy[SUNRPC_A_IP_MAP_EXPIRY + 1]; +extern const struct nla_policy sunrpc_unix_gid_nl_policy[SUNRPC_A_UNIX_GID_EXPIRY + 1]; + +int sunrpc_nl_ip_map_get_reqs_dumpit(struct sk_buff *skb, + struct netlink_callback *cb); +int sunrpc_nl_ip_map_set_reqs_doit(struct sk_buff *skb, struct genl_info *info); +int sunrpc_nl_unix_gid_get_reqs_dumpit(struct sk_buff *skb, + struct netlink_callback *cb); +int sunrpc_nl_unix_gid_set_reqs_doit(struct sk_buff *skb, + struct genl_info *info); +int sunrpc_nl_cache_flush_doit(struct sk_buff *skb, struct genl_info *info); + +enum { + SUNRPC_NLGRP_NONE, + SUNRPC_NLGRP_EXPORTD, +}; + +extern struct genl_family sunrpc_nl_family; + +#endif /* _LINUX_SUNRPC_GEN_H */ -- cgit v1.3.1