From 50b7d85680086126d7bd91dae81d57d4cb1ab6b7 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 15 Oct 2020 20:13:04 -0700 Subject: [PATCH] ramfs: fix nommu mmap with gaps in the page cache ramfs needs to check that pages are both physically contiguous and contiguous in the file. If the page cache happens to have, eg, page A for index 0 of the file, no page for index 1, and page A+1 for index 2, then an mmap of the first two pages of the file will succeed when it should fail. Fixes: 642fb4d1f1dd ("[PATCH] NOMMU: Provide shared-writable mmap support on ramfs") Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton Cc: David Howells Link: https://lkml.kernel.org/r/20200914122239.GO6583@casper.infradead.org Signed-off-by: Linus Torvalds --- fs/ramfs/file-nommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c index 414695454956..355523f4a4bf 100644 --- a/fs/ramfs/file-nommu.c +++ b/fs/ramfs/file-nommu.c @@ -224,7 +224,7 @@ static unsigned long ramfs_nommu_get_unmapped_area(struct file *file, if (!pages) goto out_free; - nr = find_get_pages(inode->i_mapping, &pgoff, lpages, pages); + nr = find_get_pages_contig(inode->i_mapping, pgoff, lpages, pages); if (nr != lpages) goto out_free_pages; /* leave if some pages were missing */