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 --- Documentation/ABI/testing/devlink-resource-mlxsw | 33 ++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/ABI/testing/devlink-resource-mlxsw (limited to 'Documentation/ABI/testing/devlink-resource-mlxsw') diff --git a/Documentation/ABI/testing/devlink-resource-mlxsw b/Documentation/ABI/testing/devlink-resource-mlxsw new file mode 100644 index 000000000..259ed2948 --- /dev/null +++ b/Documentation/ABI/testing/devlink-resource-mlxsw @@ -0,0 +1,33 @@ +What: /kvd/ +Date: 08-Jan-2018 +KernelVersion: v4.16 +Contact: mlxsw@mellanox.com +Description: The main database in the Spectrum device is a centralized + KVD database used for many of the tables used to configure + the chip including L2 FDB, L3 LPM, ECMP and more. The KVD + is divided into two sections, the first is hash-based table + and the second is a linear access table. The division + between the linear and hash-based sections is static and + require reload before the changes take effect. + +What: /kvd/linear +Date: 08-Jan-2018 +KernelVersion: v4.16 +Contact: mlxsw@mellanox.com +Description: The linear section of the KVD is managed by software as a + flat memory accessed using an index. + +What: /kvd/hash_single +Date: 08-Jan-2018 +KernelVersion: v4.16 +Contact: mlxsw@mellanox.com +Description: The hash based section of the KVD is managed by the switch + device. Used in case the key size is smaller or equal to + 64bit. + +What: /kvd/hash_double +Date: 08-Jan-2018 +KernelVersion: v4.16 +Contact: mlxsw@mellanox.com +Description: The hash based section of the KVD is managed by the switch + device. Used in case the key is larger than 64 bit. -- cgit v1.3.1