9P: Cast to loff_t before multiplying

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: fb89b45cdf ("9P: introduction of a new cache=mmap model.")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2020-10-04 19:04:22 +01:00 committed by Dominique Martinet
parent 549738f15d
commit f5f7ab168b
1 changed files with 2 additions and 2 deletions

View File

@ -612,9 +612,9 @@ 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),
};