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/gpu/amdgpu/flashing.rst | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/gpu/amdgpu/flashing.rst (limited to 'Documentation/gpu/amdgpu/flashing.rst') diff --git a/Documentation/gpu/amdgpu/flashing.rst b/Documentation/gpu/amdgpu/flashing.rst new file mode 100644 index 000000000..bd745c42a --- /dev/null +++ b/Documentation/gpu/amdgpu/flashing.rst @@ -0,0 +1,33 @@ +======================= + dGPU firmware flashing +======================= + +IFWI +---- +Flashing the dGPU integrated firmware image (IFWI) is supported by GPUs that +use the PSP to orchestrate the update (Navi3x or newer GPUs). +For supported GPUs, `amdgpu` will export a series of sysfs files that can be +used for the flash process. + +The IFWI flash process is: + +1. Ensure the IFWI image is intended for the dGPU on the system. +2. "Write" the IFWI image to the sysfs file `psp_vbflash`. This will stage the IFWI in memory. +3. "Read" from the `psp_vbflash` sysfs file to initiate the flash process. +4. Poll the `psp_vbflash_status` sysfs file to determine when the flash process completes. + +USB-C PD F/W +------------ +On GPUs that support flashing an updated USB-C PD firmware image, the process +is done using the `usbc_pd_fw` sysfs file. + +* Reading the file will provide the current firmware version. +* Writing the name of a firmware payload stored in `/lib/firmware/amdgpu` to the sysfs file will initiate the flash process. + +The firmware payload stored in `/lib/firmware/amdgpu` can be named any name +as long as it doesn't conflict with other existing binaries that are used by +`amdgpu`. + +sysfs files +----------- +.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c -- cgit v1.3.1