[PATCH v5 09/36] vmlinux.lds.h: Add .gnu.version* to COMMON_DISCARDS

Kees Cook
2020-07-31T23:08:41Z

For vmlinux linking, no architecture uses the .gnu.version* sections,
so remove it via the COMMON_DISCARDS macro in preparation for adding
--orphan-handling=warn more widely. This is a work-around for what
appears to be a bug[1] in ld.bfd which warns for this synthetic section
even when none is found in input objects, and even when no section is
emitted for an output object[2].

[1] https://sourceware.org/bugzilla/show_bug.cgi?id=26153
[2] https://lore.kernel.org/lkml/202006221524.CEB86E036B@keescook/

Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
include/asm-generic/vmlinux.lds.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index ff65a20faf4c..22985cf02130 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -933,7 +933,9 @@
#define COMMON_DISCARDS \
*(.discard) \
*(.discard.*) \
- *(.modinfo)
+ *(.modinfo) \
+ /* ld.bfd warns about .gnu.version* even when not emitted */ \
+ *(.gnu.version*) \

#define DISCARDS \
/DISCARD/ : { \
--
2.25.1