[PATCH 06/11] locale: Fix UB on insert_weights

Adhemerval Zanella adhemerval.zanella@linaro.org
Wed May 7 14:17:24 GMT 2025


The ubsan triggers:

UBSAN: Undefined behaviour in programs/ld-collate.c:862:5 null pointer passed as argument 2, nonnull attribute declared at unknown:0:0,

The memcpy is only requires if current 'weights' is nonnull, so
check it before calling it.
---
 locale/programs/ld-collate.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/locale/programs/ld-collate.c b/locale/programs/ld-collate.c
index 7de3ba064d..4fa08bd273 100644
--- a/locale/programs/ld-collate.c
+++ b/locale/programs/ld-collate.c
@@ -858,7 +858,8 @@ insert_weights (struct linereader *ldfile, struct element_t *elem,
 		  max += 10;
 		  newp = (struct element_t **)
 		    alloca (max * sizeof (struct element_t *));
-		  memcpy (newp, weights, cnt * sizeof (struct element_t *));
+		  if (weights != NULL)
+		    memcpy (newp, weights, cnt * sizeof (struct element_t *));
 		  weights = newp;
 		}
 	      weights[cnt++] = charelem;
-- 
2.43.0



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