summaryrefslogtreecommitdiffstats
path: root/kernel/Makefile
diff options
context:
space:
mode:
authorDmitry Vyukov <dvyukov@google.com>2020-12-16 05:46:46 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-16 07:46:19 +0100
commitc1cb05e77f8e3ec89eec7bed64af07cd20ed24de (patch)
treeab165480ee3fbf898a9de293f75952f2e3e46cbb /kernel/Makefile
parentubsan: expand tests and reporting (diff)
downloadlinux-c1cb05e77f8e3ec89eec7bed64af07cd20ed24de.tar.xz
linux-c1cb05e77f8e3ec89eec7bed64af07cd20ed24de.zip
kcov: don't instrument with UBSAN
Both KCOV and UBSAN use compiler instrumentation. If UBSAN detects a bug in KCOV, it may cause infinite recursion via printk and other common functions. We already don't instrument KCOV with KASAN/KCSAN for this reason, don't instrument it with UBSAN as well. As a side effect this also resolves the following gcc warning: conflicting types for built-in function '__sanitizer_cov_trace_switch'; expected 'void(long unsigned int, void *)' [-Wbuiltin-declaration-mismatch] It's only reported when kcov.c is compiled with any of the sanitizers enabled. Size of the arguments is correct, it's just that gcc uses 'long' on 64-bit arches and 'long long' on 32-bit arches, while kernel type is always 'long long'. Link: https://lkml.kernel.org/r/20201209100152.2492072-1-dvyukov@google.com Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Suggested-by: Marco Elver <elver@google.com> Acked-by: Marco Elver <elver@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/Makefile')
-rw-r--r--kernel/Makefile3
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index dddf51266719..aa7368c7eabf 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -34,8 +34,11 @@ KCOV_INSTRUMENT_extable.o := n
KCOV_INSTRUMENT_stacktrace.o := n
# Don't self-instrument.
KCOV_INSTRUMENT_kcov.o := n
+# If sanitizers detect any issues in kcov, it may lead to recursion
+# via printk, etc.
KASAN_SANITIZE_kcov.o := n
KCSAN_SANITIZE_kcov.o := n
+UBSAN_SANITIZE_kcov.o := n
CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector
obj-y += sched/