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-rw-r--r--fs/iomap/swapfile.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c
index a648dbf6991e..a5e478de1417 100644
--- a/fs/iomap/swapfile.c
+++ b/fs/iomap/swapfile.c
@@ -170,6 +170,16 @@ int iomap_swapfile_activate(struct swap_info_struct *sis,
 			return ret;
 	}
 
+	/*
+	 * If this swapfile doesn't contain even a single page-aligned
+	 * contiguous range of blocks, reject this useless swapfile to
+	 * prevent confusion later on.
+	 */
+	if (isi.nr_pages == 0) {
+		pr_warn("swapon: Cannot find a single usable page in file.\n");
+		return -EINVAL;
+	}
+
 	*pagespan = 1 + isi.highest_ppage - isi.lowest_ppage;
 	sis->max = isi.nr_pages;
 	sis->pages = isi.nr_pages - 1;