Fix NV0080_CTRL_CMD_GPU_GET_CLASSLIST to use RMAPI_PARAM_COPY_MAX_PAR…

…AMS_SIZE.

Earlier we were using a smaller limit (NV0080_CTRL_GPU_CLASSLIST_MAX_SIZE=160)
for the class list size. But Nvidia driver uses a 1 MB limit defined by
RMAPI_PARAM_COPY_MAX_PARAMS_SIZE.

Fixes 2939052 ("Add unimplemented commands used by
DeviceGetComputeRunningProcesses")

PiperOrigin-RevId: 601246811

pkg/abi/nvgpu/ctrl.go

@@ -19,6 +19,14 @@ const (
 	RM_GSS_LEGACY_MASK = 0x00008000
 )
 
+// From src/nvidia/inc/kernel/rmapi/param_copy.h:
+const (
+	// RMAPI_PARAM_COPY_MAX_PARAMS_SIZE is the size limit imposed while copying
+	// "embedded pointers" in rmapi parameter structs.
+	// See src/nvidia/src/kernel/rmapi/param_copy.c:rmapiParamsAcquire().
+	RMAPI_PARAM_COPY_MAX_PARAMS_SIZE = 1 * 1024 * 1024
+)
+
 // From src/common/sdk/nvidia/inc/ctrl/ctrlxxxx.h:
 
 // +marshal
@@ -95,12 +103,10 @@ const (
 	NV0080_CTRL_CMD_GPU_QUERY_SW_STATE_PERSISTENCE = 0x800288
 	NV0080_CTRL_CMD_GPU_GET_VIRTUALIZATION_MODE    = 0x800289
 	NV0080_CTRL_CMD_GPU_GET_CLASSLIST_V2           = 0x800292
-
-	NV0080_CTRL_GPU_CLASSLIST_MAX_SIZE = 160
 )
 
 // +marshal
-type NV0080_CTRL_CMD_GPU_GET_CLASSLIST_PARAMS struct {
+type NV0080_CTRL_GPU_GET_CLASSLIST_PARAMS struct {
 	NumClasses uint32
 	Pad        [4]byte
 	ClassList  P64

pkg/sentry/devices/nvproxy/frontend.go

@@ -549,6 +549,13 @@ func rmControlSimple(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters
 	return n, nil
 }
 
+func ctrlCmdFailWithStatus(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters, status uint32) error {
+	outIoctlParams := *ioctlParams
+	outIoctlParams.Status = status
+	_, err := outIoctlParams.CopyOut(fi.t, fi.ioctlParamsAddr)
+	return err
+}
+
 func ctrlClientSystemGetBuildVersion(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters) (uintptr, error) {
 	var ctrlParams nvgpu.NV0000_CTRL_SYSTEM_GET_BUILD_VERSION_PARAMS
 	if ctrlParams.SizeBytes() != int(ioctlParams.ParamsSize) {
@@ -588,8 +595,10 @@ func ctrlClientSystemGetBuildVersion(fi *frontendIoctlState, ioctlParams *nvgpu.
 }
 
 func ctrlDevGpuGetClasslist(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters) (uintptr, error) {
-	var ctrlParams nvgpu.NV0080_CTRL_CMD_GPU_GET_CLASSLIST_PARAMS
-
+	var ctrlParams nvgpu.NV0080_CTRL_GPU_GET_CLASSLIST_PARAMS
+	if ctrlParams.SizeBytes() != int(ioctlParams.ParamsSize) {
+		return 0, linuxerr.EINVAL
+	}
 	if _, err := ctrlParams.CopyIn(fi.t, addrFromP64(ioctlParams.Params)); err != nil {
 		return 0, err
 	}
@@ -600,10 +609,12 @@ func ctrlDevGpuGetClasslist(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Par
 		return rmControlSimple(fi, ioctlParams)
 	}
 
-	// classList pointer is not NULL. Do classList buffer management.
-	if ctrlParams.NumClasses > nvgpu.NV0080_CTRL_GPU_CLASSLIST_MAX_SIZE {
-		fi.ctx.Warningf("nvproxy: requested classlist size exceeds max (%d > %d)", ctrlParams.NumClasses, nvgpu.NV0080_CTRL_GPU_CLASSLIST_MAX_SIZE)
-		return 0, linuxerr.EINVAL
+	// classList pointer is not NULL. Check classList size against limit. See
+	// src/nvidia/src/kernel/rmapi/embedded_param_copy.c:embeddedParamCopyIn() =>
+	// case NV0080_CTRL_CMD_GPU_GET_CLASSLIST => RMAPI_PARAM_COPY_INIT().
+	// paramCopy.paramsSize is initialized as numClasses * sizeof(NvU32).
+	if ctrlParams.NumClasses*4 > nvgpu.RMAPI_PARAM_COPY_MAX_PARAMS_SIZE {
+		return 0, ctrlCmdFailWithStatus(fi, ioctlParams, nvgpu.NV_ERR_INVALID_ARGUMENT)
 	}
 
 	classList := make([]uint32, ctrlParams.NumClasses)

pkg/sentry/devices/nvproxy/frontend_unsafe.go

@@ -75,7 +75,7 @@ func ctrlClientSystemGetBuildVersionInvoke(fi *frontendIoctlState, ioctlParams *
 	return n, nil
 }
 
-func ctrlDevGpuGetClasslistInvoke(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters, ctrlParams *nvgpu.NV0080_CTRL_CMD_GPU_GET_CLASSLIST_PARAMS, classList []uint32) (uintptr, error) {
+func ctrlDevGpuGetClasslistInvoke(fi *frontendIoctlState, ioctlParams *nvgpu.NVOS54Parameters, ctrlParams *nvgpu.NV0080_CTRL_GPU_GET_CLASSLIST_PARAMS, classList []uint32) (uintptr, error) {
 	sentryCtrlParams := *ctrlParams
 	sentryCtrlParams.ClassList = p64FromPtr(unsafe.Pointer(&classList[0]))
 	n, err := rmControlInvoke(fi, ioctlParams, &sentryCtrlParams)