uefi runtime: Increase default size of name buffer

uefi/CHANGELOG.md

@@ -22,6 +22,8 @@
   zero. The allocation is retried instead, and in all failure cases an error is
   returned rather than panicking.
 - The `Display` impl for `CStr8` now excludes the trailing null character.
+- `VariableKeys` initializes with a larger name buffer to work around firmware
+  bugs on some devices.
 
 
 # uefi - 0.34.1 (2025-02-07)

uefi/src/runtime.rs

@@ -16,8 +16,12 @@ use uefi_raw::table::boot::MemoryDescriptor;
 
 #[cfg(feature = "alloc")]
 use {
-    crate::mem::make_boxed, crate::CString16, crate::Guid, alloc::borrow::ToOwned,
-    alloc::boxed::Box, alloc::vec::Vec,
+    crate::mem::make_boxed,
+    crate::CString16,
+    crate::Guid,
+    alloc::borrow::ToOwned,
+    alloc::boxed::Box,
+    alloc::{vec, vec::Vec},
 };
 
 #[cfg(all(feature = "unstable", feature = "alloc"))]
@@ -268,13 +272,14 @@ pub struct VariableKeys {
 #[cfg(feature = "alloc")]
 impl VariableKeys {
     fn new() -> Self {
-        // Create a the name buffer with a reasonable default capacity, and
-        // initialize it to an empty null-terminated string.
-        let mut name = Vec::with_capacity(32);
-        name.push(0);
+        // Create a name buffer with a large default size and zero
+        // initialize it. A Toshiba Satellite Pro R50-B-12P was found
+        // to not correctly update the VariableNameSize passed into
+        // GetNextVariableName and starting with a large buffer works
+        // around this issue.
+        let name = vec![0; 512];
 
         Self {
-            // Give the name buffer a reasonable default capacity.
             name,
             // The initial vendor GUID is arbitrary.
             vendor: VariableVendor(Guid::default()),