From: Tavian Barnes <tavianator@tavianator.com>
Date: Fri, 21 Jun 2024 20:39:58 +0000 (-0400)
Subject: bcachefs: varint: Avoid left-shift of a negative value
X-Git-Tag: v6.11-rc1~120^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ee1b8dc17ac367f3fbea18fee4f7825eb11eb757;p=thirdparty%2Fkernel%2Flinux.git

bcachefs: varint: Avoid left-shift of a negative value

Shifting a negative value left is undefined.

Signed-off-by: Tavian Barnes <tavianator@tavianator.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---

diff --git a/fs/bcachefs/varint.c b/fs/bcachefs/varint.c
index cb4f33ed9ab37..a9ebcd82c6025 100644
--- a/fs/bcachefs/varint.c
+++ b/fs/bcachefs/varint.c
@@ -85,7 +85,7 @@ int bch2_varint_encode_fast(u8 *out, u64 v)
 
 	if (likely(bytes < 9)) {
 		v <<= bytes;
-		v |= ~(~0 << (bytes - 1));
+		v |= ~(~0U << (bytes - 1));
 	} else {
 		*out++ = 255;
 		bytes = 9;