kernel/shared_memory: Sanitize supplied size when unmapping

The kernel makes sure that the given size to unmap is always the same
size as the entire region managed by the shared memory instance,
otherwise it returns an error code signifying an invalid size.

This is similarly done for transfer memory (which we already check for).

1 files changed, 9 insertions, 1 deletions

diff --git a/src/core/hle/kernel/shared_memory.cpp b/src/core/hle/kernel/shared_memory.cpp
index 62861da36..273e6a25e 100644
--- a/src/core/hle/kernel/shared_memory.cpp
+++ b/src/core/hle/kernel/shared_memory.cpp
@@ -119,7 +119,15 @@ ResultCode SharedMemory::Map(Process& target_process, VAddr address, MemoryPermi
                                                      ConvertPermissions(permissions));
 }
 
-ResultCode SharedMemory::Unmap(Process& target_process, VAddr address) {
+ResultCode SharedMemory::Unmap(Process& target_process, VAddr address, u64 unmap_size) {
+    if (unmap_size != size) {
+        LOG_ERROR(Kernel,
+                  "Invalid size passed to Unmap. Size must be equal to the size of the "
+                  "memory managed. Shared memory size=0x{:016X}, Unmap size=0x{:016X}",
+                  size, unmap_size);
+        return ERR_INVALID_SIZE;
+    }
+
     // TODO(Subv): Verify what happens if the application tries to unmap an address that is not
     // mapped to a SharedMemory.
     return target_process.VMManager().UnmapRange(address, size);