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/9p/Kconfig | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 net/9p/Kconfig (limited to 'net/9p/Kconfig') diff --git a/net/9p/Kconfig b/net/9p/Kconfig new file mode 100644 index 000000000..22f8c1678 --- /dev/null +++ b/net/9p/Kconfig @@ -0,0 +1,63 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# 9P protocol configuration +# + +menuconfig NET_9P + tristate "Plan 9 Resource Sharing Support (9P2000)" + select NETFS_SUPPORT + help + If you say Y here, you will get experimental support for + Plan 9 resource sharing via the 9P2000 protocol. + + See for more information. + + If unsure, say N. + +if NET_9P + +config NET_9P_FD + default NET_9P + imply INET + imply UNIX + tristate "9P FD Transport" + help + This builds support for transports over TCP, Unix sockets and + filedescriptors. + +config NET_9P_VIRTIO + depends on VIRTIO + tristate "9P Virtio Transport" + help + This builds support for a transports between + guest partitions and a host partition. + +config NET_9P_XEN + depends on XEN + select XEN_XENBUS_FRONTEND + tristate "9P Xen Transport" + help + This builds support for a transport for 9pfs between + two Xen domains. + +config NET_9P_USBG + tristate "9P USB Gadget Transport" + depends on USB_GADGET + select CONFIGFS_FS + select USB_LIBCOMPOSITE + help + This builds support for a transport for 9pfs over + usb gadget. + +config NET_9P_RDMA + depends on INET && INFINIBAND && INFINIBAND_ADDR_TRANS + tristate "9P RDMA Transport (Experimental)" + help + This builds support for an RDMA transport. + +config NET_9P_DEBUG + bool "Debug information" + help + Say Y if you want the 9P subsystem to log debug information. + +endif -- cgit v1.3.1