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From:   Jia Zhu <zhujia.zj@bytedance.com>
To:     linux-erofs@lists.ozlabs.org
Cc:     linux-kernel@vger.kernel.org, jefflexu@linux.alibaba.com,
        yinxin.x@bytedance.com, xiang@kernel.org,
        Jia Zhu <zhujia.zj@bytedance.com>
Subject: [PATCH] erofs: explicit cast blkaddr to u64 before shift operation
Date:   Thu, 13 Apr 2023 11:57:34 +0800
Message-Id: <20230413035734.15457-1-zhujia.zj@bytedance.com>
MIME-Version: 1.0
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Precedence: bulk

We should explicitly cast @blkaddr from u32 to u64 before the shift
operation to return the larger type.

Fixes: b1c2d99b18ff ("erofs: avoid hardcoded blocksize for subpage block support")
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
---
 fs/erofs/data.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index aa7f9e4f86fb..6fe9a779fa91 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -35,7 +35,7 @@ void *erofs_bread(struct erofs_buf *buf, erofs_blk_t blkaddr,
 		  enum erofs_kmap_type type)
 {
 	struct inode *inode = buf->inode;
-	erofs_off_t offset = blkaddr << inode->i_blkbits;
+	erofs_off_t offset = (erofs_off_t)blkaddr << inode->i_blkbits;
 	pgoff_t index = offset >> PAGE_SHIFT;
 	struct page *page = buf->page;
 	struct folio *folio;
-- 
2.20.1