rusticl: check for overrun status when deserializing

Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32253>
(cherry picked from commit 813edb6cea)

.pick_status.json

@@ -954,7 +954,7 @@
         "description": "rusticl: check for overrun status when deserializing",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null,
         "notes": null

src/gallium/frontends/rusticl/core/kernel.rs

@@ -25,6 +25,7 @@ use std::convert::TryInto;
 use std::fmt::Debug;
 use std::fmt::Display;
 use std::ops::Index;
+use std::ops::Not;
 use std::os::raw::c_void;
 use std::ptr;
 use std::slice;
@@ -58,8 +59,10 @@ pub enum KernelArgType {
 
 impl KernelArgType {
     fn deserialize(blob: &mut blob_reader) -> Option<Self> {
-        Some(match unsafe { blob_read_uint8(blob) } {
+        // SAFETY: we get 0 on an overrun, but we verify that later and act accordingly.
+        let res = match unsafe { blob_read_uint8(blob) } {
             0 => {
+                // SAFETY: same here
                 let size = unsafe { blob_read_uint16(blob) };
                 KernelArgType::Constant(size)
             }
@@ -71,7 +74,9 @@ impl KernelArgType {
             6 => KernelArgType::MemConstant,
             7 => KernelArgType::MemLocal,
             _ => return None,
-        })
+        };
+
+        blob.overrun.not().then_some(res)
     }
 
     fn serialize(&self, blob: &mut blob) {
@@ -192,13 +197,14 @@ impl KernelArg {
     }
 
     fn deserialize(blob: &mut blob_reader) -> Option<Vec<Self>> {
-        unsafe {
-            let len = blob_read_uint16(blob) as usize;
+        // SAFETY: we check the overrun status, blob_read returns 0 in such a case.
+        let len = unsafe { blob_read_uint16(blob) } as usize;
         let mut res = Vec::with_capacity(len);
 
         for _ in 0..len {
             let spirv = spirv::SPIRVKernelArg::deserialize(blob)?;
-                let dead = blob_read_uint8(blob) != 0;
+            // SAFETY: we check the overrun status
+            let dead = unsafe { blob_read_uint8(blob) } != 0;
             let kind = KernelArgType::deserialize(blob)?;
 
             res.push(Self {
@@ -208,8 +214,7 @@ impl KernelArg {
             });
         }
 
-            Some(res)
-        }
+        blob.overrun.not().then_some(res)
     }
 }
 
@@ -1080,18 +1085,16 @@ impl SPIRVToNirResult {
         let args = KernelArg::deserialize(&mut reader)?;
         let default_build = CompilationResult::deserialize(&mut reader, d)?;
 
+        // SAFETY: on overrun this returns 0
         let optimized = match unsafe { blob_read_uint8(&mut reader) } {
             0 => None,
             _ => Some(CompilationResult::deserialize(&mut reader, d)?),
         };
 
-        Some(SPIRVToNirResult::new(
-            d,
-            kernel_info,
-            args,
-            default_build,
-            optimized,
-        ))
+        reader
+            .overrun
+            .not()
+            .then(|| SPIRVToNirResult::new(d, kernel_info, args, default_build, optimized))
     }
 
     // we can't use Self here as the nir shader might be compiled to a cso already and we can't

src/gallium/frontends/rusticl/mesa/compiler/clc/spirv.rs

@@ -9,6 +9,7 @@ use mesa_rust_util::string::*;
 
 use std::ffi::CString;
 use std::fmt::Debug;
+use std::ops::Not;
 use std::os::raw::c_char;
 use std::os::raw::c_void;
 use std::ptr;
@@ -484,7 +485,8 @@ impl SPIRVKernelArg {
                 _ => return None,
             };
 
-            Some(Self {
+            // check overrun to ensure nothing went wrong
+            blob.overrun.not().then(|| Self {
                 name: String::from_utf8_unchecked(name.to_owned()),
                 type_name: String::from_utf8_unchecked(type_name.to_owned()),
                 access_qualifier: clc_kernel_arg_access_qualifier(access_qualifier),

src/gallium/frontends/rusticl/mesa/compiler/nir.rs

@@ -5,6 +5,7 @@ use mesa_rust_util::offset_of;
 use std::convert::TryInto;
 use std::ffi::CString;
 use std::marker::PhantomData;
+use std::ops::Not;
 use std::ptr;
 use std::ptr::NonNull;
 use std::slice;
@@ -158,7 +159,9 @@ impl NirShader {
         blob: &mut blob_reader,
         options: *const nir_shader_compiler_options,
     ) -> Option<Self> {
-        unsafe { Self::new(nir_deserialize(ptr::null_mut(), options, blob)) }
+        // we already create the NirShader here so it gets automatically deallocated on overrun.
+        let nir = Self::new(unsafe { nir_deserialize(ptr::null_mut(), options, blob) })?;
+        blob.overrun.not().then_some(nir)
     }
 
     pub fn serialize(&self, blob: &mut blob) {