From: Icecream95 <ixn@disroot.org>
Date: Wed, 14 Jul 2021 00:47:30 +0000 (+1200)
Subject: pan/decode: Avoid undefined behaviour on shift in bits()
X-Git-Tag: upstream/22.3.5~20200
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=04c02418d74703812a39405df14e130c2d6fd098;p=platform%2Fupstream%2Fmesa.git

pan/decode: Avoid undefined behaviour on shift in bits()

v2: Return 0 instead of `word` (Alyssa)

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11869>
---

diff --git a/src/panfrost/lib/decode.c b/src/panfrost/lib/decode.c
index 07366e4..7a67121 100644
--- a/src/panfrost/lib/decode.c
+++ b/src/panfrost/lib/decode.c
@@ -451,6 +451,9 @@ bits(u32 word, u32 lo, u32 hi)
         if (hi - lo >= 32)
                 return word; // avoid undefined behavior with the shift
 
+        if (lo >= 32)
+                return 0;
+
         return (word >> lo) & ((1 << (hi - lo)) - 1);
 }