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/llc_if.h | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 include/net/llc_if.h (limited to 'include/net/llc_if.h') diff --git a/include/net/llc_if.h b/include/net/llc_if.h new file mode 100644 index 000000000..a33325961 --- /dev/null +++ b/include/net/llc_if.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef LLC_IF_H +#define LLC_IF_H +/* + * Copyright (c) 1997 by Procom Technology,Inc. + * 2001 by Arnaldo Carvalho de Melo + */ +/* Defines LLC interface to network layer */ +/* Available primitives */ +#include +#include +#include +#include +#include + +#define LLC_DATAUNIT_PRIM 1 +#define LLC_CONN_PRIM 2 +#define LLC_DATA_PRIM 3 +#define LLC_DISC_PRIM 4 +#define LLC_RESET_PRIM 5 +#define LLC_FLOWCONTROL_PRIM 6 /* Not supported at this time */ +#define LLC_DISABLE_PRIM 7 +#define LLC_XID_PRIM 8 +#define LLC_TEST_PRIM 9 +#define LLC_SAP_ACTIVATION 10 +#define LLC_SAP_DEACTIVATION 11 + +#define LLC_NBR_PRIMITIVES 11 + +#define LLC_IND 1 +#define LLC_CONFIRM 2 + +/* Primitive type */ +#define LLC_PRIM_TYPE_REQ 1 +#define LLC_PRIM_TYPE_IND 2 +#define LLC_PRIM_TYPE_RESP 3 +#define LLC_PRIM_TYPE_CONFIRM 4 + +/* Reset reasons, remote entity or local LLC */ +#define LLC_RESET_REASON_REMOTE 1 +#define LLC_RESET_REASON_LOCAL 2 + +/* Disconnect reasons */ +#define LLC_DISC_REASON_RX_DM_RSP_PDU 0 +#define LLC_DISC_REASON_RX_DISC_CMD_PDU 1 +#define LLC_DISC_REASON_ACK_TMR_EXP 2 + +/* Confirm reasons */ +#define LLC_STATUS_CONN 0 /* connect confirm & reset confirm */ +#define LLC_STATUS_DISC 1 /* connect confirm & reset confirm */ +#define LLC_STATUS_FAILED 2 /* connect confirm & reset confirm */ +#define LLC_STATUS_IMPOSSIBLE 3 /* connect confirm */ +#define LLC_STATUS_RECEIVED 4 /* data conn */ +#define LLC_STATUS_REMOTE_BUSY 5 /* data conn */ +#define LLC_STATUS_REFUSE 6 /* data conn */ +#define LLC_STATUS_CONFLICT 7 /* disconnect conn */ +#define LLC_STATUS_RESET_DONE 8 /* */ + +int llc_establish_connection(struct sock *sk, const u8 *lmac, u8 *dmac, + u8 dsap); +int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb); +int llc_send_disc(struct sock *sk); +#endif /* LLC_IF_H */ -- cgit v1.3.1