From: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Fixes: fb89b45cdfdc ("9P: introduction of a new cache=mmap model.") Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Dominique Martinet <asmadeus@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/9p/vfs_file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -624,9 +624,9 @@ static void v9fs_mmap_vm_close(struct vm 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), };
