[PATCH v2] x86: um: vdso: Disable UBSAN instrumentation

From: Roberto Sassu
Date: Mon May 13 2024 - 09:12:00 EST


From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>

The UBSAN instrumentation cannot work in the vDSO since it is executing in
userspace, so disable it in the Makefile. Fixes the build failures such as:

CALL scripts/checksyscalls.sh
VDSO arch/x86/um/vdso/vdso.so.dbg
arch/x86/um/vdso/vdso.so.dbg: undefined symbols found

Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
arch/x86/um/vdso/Makefile | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/um/vdso/Makefile b/arch/x86/um/vdso/Makefile
index b86d634730b2..ca79c0de582e 100644
--- a/arch/x86/um/vdso/Makefile
+++ b/arch/x86/um/vdso/Makefile
@@ -3,8 +3,10 @@
# Building vDSO images for x86.
#

-# do not instrument on vdso because KASAN is not compatible with user mode
+# do not instrument on vdso because KASAN/UBSAN are not compatible with user
+# mode
KASAN_SANITIZE := n
+UBSAN_SANITIZE := n

# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
KCOV_INSTRUMENT := n
--
2.34.1