From 477b310dfd5ec662837e2e1cde87b9416dbcf67f Mon Sep 17 00:00:00 2001
From: Rhys Perry <pendingchaos02@gmail.com>
Date: Wed, 27 Sep 2023 15:55:25 +0100
Subject: [PATCH] util: skip zero-sized SHA1Update
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Fixes UBSan error:
src/util/sha1/sha1.c:140:8: runtime error: null pointer passed as argument 2, which is declared to never be null

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25853>
---
 src/util/mesa-sha1.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/util/mesa-sha1.h b/src/util/mesa-sha1.h
index 809fabc..c264927 100644
--- a/src/util/mesa-sha1.h
+++ b/src/util/mesa-sha1.h
@@ -44,7 +44,8 @@ _mesa_sha1_init(struct mesa_sha1 *ctx)
 static inline void
 _mesa_sha1_update(struct mesa_sha1 *ctx, const void *data, size_t size)
 {
-   SHA1Update(ctx, (const unsigned char *)data, size);
+   if (size)
+      SHA1Update(ctx, (const unsigned char *)data, size);
 }
 
 static inline void
-- 
2.7.4