Makefile: Enable -Wcast-function-type

In order to make sure new function cast mismatches are not introduced in the kernel (to avoid tripping CFI checking), the kernel should be globally built with -Wcast-function-type. Link: KSPP#20 Co-developed-by: Kees Cook <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Gustavo A. R. Silva <[email protected]>
hudan8080808 · Nov 15, 2021 · 552a23a · 552a23a
1 parent fa55b7d
commit 552a23a
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/Makefile b/Makefile
@@ -953,6 +953,11 @@ KBUILD_CFLAGS += -Wvla
 # disable pointer signed / unsigned warnings in gcc 4.0
 KBUILD_CFLAGS += -Wno-pointer-sign
 
+# In order to make sure new function cast mismatches are not introduced
+# in the kernel (to avoid tripping CFI checking), the kernel should be
+# globally built with -Wcast-function-type.
+KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
+
 # disable stringop warnings in gcc 8+
 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)