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/ethtool/linkinfo.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 net/ethtool/linkinfo.c (limited to 'net/ethtool/linkinfo.c') diff --git a/net/ethtool/linkinfo.c b/net/ethtool/linkinfo.c new file mode 100644 index 000000000..d5b3dbc53 --- /dev/null +++ b/net/ethtool/linkinfo.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include "common.h" +#include "netlink.h" + +struct linkinfo_req_info { + struct ethnl_req_info base; +}; + +struct linkinfo_reply_data { + struct ethnl_reply_data base; + struct ethtool_link_ksettings ksettings; + struct ethtool_link_settings *lsettings; +}; + +#define LINKINFO_REPDATA(__reply_base) \ + container_of(__reply_base, struct linkinfo_reply_data, base) + +const struct nla_policy ethnl_linkinfo_get_policy[] = { + [ETHTOOL_A_LINKINFO_HEADER] = + NLA_POLICY_NESTED(ethnl_header_policy), +}; + +static int linkinfo_prepare_data(const struct ethnl_req_info *req_base, + struct ethnl_reply_data *reply_base, + const struct genl_info *info) +{ + struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base); + struct net_device *dev = reply_base->dev; + int ret; + + data->lsettings = &data->ksettings.base; + + ret = ethnl_ops_begin(dev); + if (ret < 0) + return ret; + ret = netif_get_link_ksettings(dev, &data->ksettings); + if (ret < 0) + GENL_SET_ERR_MSG(info, "failed to retrieve link settings"); + ethnl_ops_complete(dev); + + return ret; +} + +static int linkinfo_reply_size(const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + return nla_total_size(sizeof(u8)) /* LINKINFO_PORT */ + + nla_total_size(sizeof(u8)) /* LINKINFO_PHYADDR */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX_CTRL */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TRANSCEIVER */ + + 0; +} + +static int linkinfo_fill_reply(struct sk_buff *skb, + const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + const struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base); + + if (nla_put_u8(skb, ETHTOOL_A_LINKINFO_PORT, data->lsettings->port) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_PHYADDR, + data->lsettings->phy_address) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX, + data->lsettings->eth_tp_mdix) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX_CTRL, + data->lsettings->eth_tp_mdix_ctrl) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TRANSCEIVER, + data->lsettings->transceiver)) + return -EMSGSIZE; + + return 0; +} + +/* LINKINFO_SET */ + +const struct nla_policy ethnl_linkinfo_set_policy[] = { + [ETHTOOL_A_LINKINFO_HEADER] = + NLA_POLICY_NESTED(ethnl_header_policy), + [ETHTOOL_A_LINKINFO_PORT] = { .type = NLA_U8 }, + [ETHTOOL_A_LINKINFO_PHYADDR] = { .type = NLA_U8 }, + [ETHTOOL_A_LINKINFO_TP_MDIX_CTRL] = { .type = NLA_U8 }, +}; + +static int +ethnl_set_linkinfo_validate(struct ethnl_req_info *req_info, + struct genl_info *info) +{ + const struct ethtool_ops *ops = req_info->dev->ethtool_ops; + + if (!ops->get_link_ksettings || !ops->set_link_ksettings) + return -EOPNOTSUPP; + return 1; +} + +static int +ethnl_set_linkinfo(struct ethnl_req_info *req_info, struct genl_info *info) +{ + struct ethtool_link_ksettings ksettings = {}; + struct ethtool_link_settings *lsettings; + struct net_device *dev = req_info->dev; + struct nlattr **tb = info->attrs; + bool mod = false; + int ret; + + ret = netif_get_link_ksettings(dev, &ksettings); + if (ret < 0) { + GENL_SET_ERR_MSG(info, "failed to retrieve link settings"); + return ret; + } + lsettings = &ksettings.base; + + ethnl_update_u8(&lsettings->port, tb[ETHTOOL_A_LINKINFO_PORT], &mod); + ethnl_update_u8(&lsettings->phy_address, tb[ETHTOOL_A_LINKINFO_PHYADDR], + &mod); + ethnl_update_u8(&lsettings->eth_tp_mdix_ctrl, + tb[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL], &mod); + if (!mod) + return 0; + + ret = dev->ethtool_ops->set_link_ksettings(dev, &ksettings); + if (ret < 0) { + GENL_SET_ERR_MSG(info, "link settings update failed"); + return ret; + } + + return 1; +} + +const struct ethnl_request_ops ethnl_linkinfo_request_ops = { + .request_cmd = ETHTOOL_MSG_LINKINFO_GET, + .reply_cmd = ETHTOOL_MSG_LINKINFO_GET_REPLY, + .hdr_attr = ETHTOOL_A_LINKINFO_HEADER, + .req_info_size = sizeof(struct linkinfo_req_info), + .reply_data_size = sizeof(struct linkinfo_reply_data), + + .prepare_data = linkinfo_prepare_data, + .reply_size = linkinfo_reply_size, + .fill_reply = linkinfo_fill_reply, + + .set_validate = ethnl_set_linkinfo_validate, + .set = ethnl_set_linkinfo, + .set_ntf_cmd = ETHTOOL_MSG_LINKINFO_NTF, +}; -- cgit v1.3.1