[UNSTABLE][PATCH 2/5] UBUNTU: SAUCE: objtool: make objtool SLS validation fatal when building with CONFIG_SLS=y

[Dimitri John Ledkov]

BugLink: https://bugs.launchpad.net/bugs/2046440

Make objtool SLS validation fatal when building with CONFIG_SLS=y,
currently it is a build.log warning only.

This is a standalone patch, such that if regressions are identified
(with any config or toolchain configuration) it can be reverted until
relevant identified code is fixed up or otherwise
ignored/silecned/marked as safe.

Signed-off-by: Dimitri John Ledkov <dimitri.ledkov at canonical.com>
Link: https://lore.kernel.org/all/20231213134303.2302285-3-dimitri.ledkov@canonical.com/
---
 tools/objtool/check.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 15df4afae2..9709f037f1 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -4500,7 +4500,9 @@ static int validate_sls(struct objtool_file *file)
 		}
 	}
 
-	return warnings;
+	/* SLS is an optional security safety feature, make it fatal
+	 * to ensure no new code is introduced that fails SLS */
+	return -warnings;
 }
 
 static bool ignore_noreturn_call(struct instruction *insn)
-- 
2.34.1