zig

commit 518dbd30cb985cd9a5d89a8201becf1bd398330e (tree)
parent 51ac8eb08e7542c25c7d3a0d1ebeac040544e4c0
Author: Andrew Kelley <andrew@ziglang.org>
Date:   Sun, 26 Jan 2020 18:52:43 -0500

Merge pull request #4133 from daurnimator/4087-free-sets-undefined

Sets memory to undefined when freed from allocator
Diffstat:
M
lib/std/http/headers.zig
 | 
2
+-
M
lib/std/mem.zig
 | 
3
+++

2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/lib/std/http/headers.zig b/lib/std/http/headers.zig
@@ -172,7 +172,7 @@ pub const Headers = struct {
             var dex = HeaderIndexList.init(self.allocator);
             try dex.append(n - 1);
             errdefer dex.deinit();
-            _ = try self.index.put(name, dex);
+            _ = try self.index.put(name_dup, dex);
         }
         self.data.appendAssumeCapacity(entry);
     }
diff --git a/lib/std/mem.zig b/lib/std/mem.zig
@@ -175,6 +175,7 @@ pub const Allocator = struct {
 
         const old_byte_slice = @sliceToBytes(old_mem);
         const byte_count = math.mul(usize, @sizeOf(T), new_n) catch return Error.OutOfMemory;
+        // Note: can't set shrunk memory to undefined as memory shouldn't be modified on realloc failure
         const byte_slice = try self.reallocFn(self, old_byte_slice, Slice.alignment, byte_count, new_alignment);
         assert(byte_slice.len == byte_count);
         if (new_n > old_mem.len) {
@@ -221,6 +222,7 @@ pub const Allocator = struct {
         const byte_count = @sizeOf(T) * new_n;
 
         const old_byte_slice = @sliceToBytes(old_mem);
+        @memset(old_byte_slice.ptr + byte_count, undefined, old_byte_slice.len - byte_count);
         const byte_slice = self.shrinkFn(self, old_byte_slice, Slice.alignment, byte_count, new_alignment);
         assert(byte_slice.len == byte_count);
         return @bytesToSlice(T, @alignCast(new_alignment, byte_slice));
@@ -234,6 +236,7 @@ pub const Allocator = struct {
         const bytes_len = bytes.len + @boolToInt(Slice.sentinel != null);
         if (bytes_len == 0) return;
         const non_const_ptr = @intToPtr([*]u8, @ptrToInt(bytes.ptr));
+        @memset(non_const_ptr, undefined, bytes_len);
         const shrink_result = self.shrinkFn(self, non_const_ptr[0..bytes_len], Slice.alignment, 0, 1);
         assert(shrink_result.len == 0);
     }