From ae44f9c286da3fbb3f827076403ea64fa9adfef2 Mon Sep 17 00:00:00 2001
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: Wed, 4 Aug 2021 20:07:34 -0700
Subject: [PATCH] iomap: Add another assertion to inline data handling

Check that the file tail does not cross a page boundary.  Requested by
Andreas.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
 fs/iomap/buffered-io.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 8ee0211bea86..586d9d078ce1 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -215,6 +215,8 @@ static int iomap_read_inline_data(struct inode *inode, struct page *page,
 	if (PageUptodate(page))
 		return PAGE_SIZE - poff;
 
+	if (WARN_ON_ONCE(size > PAGE_SIZE - poff))
+		return -EIO;
 	if (WARN_ON_ONCE(size > PAGE_SIZE -
 			 offset_in_page(iomap->inline_data)))
 		return -EIO;