[PATCH 06/14] Fix CFLAGS for UBSAN_BOUNDS on Clang

George-Aurelian Popescu
2020-09-14T17:29:42Z

From: George Popescu <georgepope@google.com>

When the kernel is compiled with Clang, UBSAN_BOUNDS inserts a brk after
the handler call, preventing it from printing any information processed
inside the buffer.
For Clang -fsanitize=bounds expands to -fsanitize=array-bounds and
-fsanitize=local-bounds, and the latter adds a brk after the handler
call

Signed-off-by: George Popescu <georgepope@google.com>
---
scripts/Makefile.ubsan | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan
index 27348029b2b8..3d15ac346c97 100644
--- a/scripts/Makefile.ubsan
+++ b/scripts/Makefile.ubsan
@@ -4,7 +4,14 @@ ifdef CONFIG_UBSAN_ALIGNMENT
endif

ifdef CONFIG_UBSAN_BOUNDS
- CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds)
+ # For Clang -fsanitize=bounds translates to -fsanitize=array-bounds and
+ # -fsanitize=local-bounds; the latter adds a brk right after the
+ # handler is called.
+ ifdef CONFIG_CC_IS_CLANG
+ CFLAGS_UBSAN += $(call cc-option, -fsanitize=array-bounds)
+ else
+ CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds)
+ endif
endif

ifdef CONFIG_UBSAN_MISC
--
2.28.0.618.gf4bc123cb7-goog