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Subject[PATCH 2/7] buffer: Promote to unsigned long long before shifting
Date
On 32-bit systems, this shift will overflow for files larger than 4GB.

Cc: stable@vger.kernel.org
Fixes: 5417169026c3 ("[FS] Implement block_page_mkwrite.")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
fs/buffer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 50bbc99e3d96..66f4765e60ee 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2515,7 +2515,7 @@ int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
}

/* page is wholly or partially inside EOF */
- if (((page->index + 1) << PAGE_SHIFT) > size)
+ if (((page->index + 1ULL) << PAGE_SHIFT) > size)
end = size & ~PAGE_MASK;
else
end = PAGE_SIZE;
--
2.28.0
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