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/atm/Kconfig | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 net/atm/Kconfig (limited to 'net/atm/Kconfig') diff --git a/net/atm/Kconfig b/net/atm/Kconfig new file mode 100644 index 000000000..dfdc3a855 --- /dev/null +++ b/net/atm/Kconfig @@ -0,0 +1,37 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Asynchronous Transfer Mode (ATM) +# + +config ATM + tristate "Asynchronous Transfer Mode (ATM)" + help + ATM is a high-speed networking technology for Local Area Networks + and Wide Area Networks. It uses a fixed packet size and is + connection oriented, allowing for the negotiation of minimum + bandwidth requirements. + + In order to participate in an ATM network, your Linux box needs an + ATM networking card. If you have that, say Y here and to the driver + of your ATM card below. + + Note that you need a set of user-space programs to actually make use + of ATM. See the file for + further details. + +config ATM_BR2684 + tristate "RFC1483/2684 Bridged protocols" + depends on ATM && INET + help + ATM PVCs can carry ethernet PDUs according to RFC2684 (formerly 1483) + This device will act like an ethernet from the kernels point of view, + with the traffic being carried by ATM PVCs (currently 1 PVC/device). + This is sometimes used over DSL lines. If in doubt, say N. + +config ATM_BR2684_IPFILTER + bool "Per-VC IP filter kludge" + depends on ATM_BR2684 + help + This is an experimental mechanism for users who need to terminate a + large number of IP-only vcc's. Do not enable this unless you are sure + you know what you are doing. -- cgit v1.3.1