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From:   George-Aurelian Popescu <georgepope@google.com>
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        George Popescu <georgepope@google.com>
Subject: [PATCH 06/14] Fix CFLAGS for UBSAN_BOUNDS on Clang
Date:   Mon, 14 Sep 2020 17:27:42 +0000
Message-Id: <20200914172750.852684-7-georgepope@google.com>
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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