From 0db6e7161e3333a2a119e592cc215909d53d8ecc Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Sun, 4 Oct 2020 19:04:22 +0100 Subject: [PATCH] 9P: Cast to loff_t before multiplying commit f5f7ab168b9a60e12a4b8f2bb6fcc91321dc23c1 upstream. On 32-bit systems, this multiplication will overflow for files larger than 4GB. Link: http://lkml.kernel.org/r/20201004180428.14494-2-willy@infradead.org Cc: stable@vger.kernel.org Fixes: fb89b45cdfdc ("9P: introduction of a new cache=mmap model.") Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Dominique Martinet Signed-off-by: Greg Kroah-Hartman --- fs/9p/vfs_file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c index fe7f0bd2048e..ee9cabac1204 100644 --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -609,9 +609,9 @@ static void v9fs_mmap_vm_close(struct vm_area_struct *vma) struct writeback_control wbc = { .nr_to_write = LONG_MAX, .sync_mode = WB_SYNC_ALL, - .range_start = vma->vm_pgoff * PAGE_SIZE, + .range_start = (loff_t)vma->vm_pgoff * PAGE_SIZE, /* absolute end, byte at end included */ - .range_end = vma->vm_pgoff * PAGE_SIZE + + .range_end = (loff_t)vma->vm_pgoff * PAGE_SIZE + (vma->vm_end - vma->vm_start - 1), };