riscv/qemu: avoid overlapped copy of init data

This fixes init data corruption by avoid copying in overlaping cases. Due to linker alignment handling, sometimes _eronly and _sdata just differes a few bytes thus copying shall be avoided. Signed-off-by: Yanfeng Liu <[email protected]>
yf13 · Aug 1, 2024 · 43614ee · 43614ee
1 parent cbb6e05
commit 43614ee
Showing 1 changed file with 8 additions and 0 deletions.
diff --git a/arch/risc-v/src/qemu-rv/qemu_rv_start.c b/arch/risc-v/src/qemu-rv/qemu_rv_start.c
@@ -100,6 +100,14 @@ static void qemu_rv_copy_data(void)
    * end of all of the other read-only data (.text, .rodata) at _eronly.
    */
 
+  /* Check overlap to avoid copying */
+
+  if (_edata - _sdata + _eronly >= _sdata &&
+      _edata - _sdata + _eronly <= _edata)
+    {
+      return;
+    }
+
   for (src = (const uint32_t *)_eronly,
        dest = (uint32_t *)_sdata; dest < (uint32_t *)_edata;
       )