From 1257bf8052bd70dbb4ad70bc23e31f19a8db3f26 Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Fri, 24 Aug 2018 10:02:40 +0800 Subject: [PATCH] staging: erofs: fix potential overflow in z_erofs_vle_normalaccess_readpage{,s} As Dan reported in the LKP mailing list: https://lists.01.org/pipermail/kbuild-all/2018-August/051558.html New smatch warnings: drivers/staging/erofs/unzip_vle.c:1359 z_erofs_vle_normalaccess_readpages() warn: should '()->index << 12' be a 64 bit type? Old smatch warnings: drivers/staging/erofs/unzip_vle.c:1322 z_erofs_vle_normalaccess_readpage() warn: should 'page->index << 12' be a 64 bit type? It needs to cast variable's type to erofs_off_t before left shifting. Reported-by: Dan Carpenter Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman --- drivers/staging/erofs/unzip_vle.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index 6c4c9280cb8c..22f9a02a75f9 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -1314,7 +1314,7 @@ static int z_erofs_vle_normalaccess_readpage(struct file *file, LIST_HEAD(pagepool); #if (EROFS_FS_ZIP_CACHE_LVL >= 2) - f.cachedzone_la = page->index << PAGE_SHIFT; + f.cachedzone_la = (erofs_off_t)page->index << PAGE_SHIFT; #endif err = z_erofs_do_read_page(&f, page, &pagepool); (void)z_erofs_vle_work_iter_end(&f.builder); @@ -1347,7 +1347,7 @@ static inline int __z_erofs_vle_normalaccess_readpages( LIST_HEAD(pagepool); #if (EROFS_FS_ZIP_CACHE_LVL >= 2) - f.cachedzone_la = lru_to_page(pages)->index << PAGE_SHIFT; + f.cachedzone_la = (erofs_off_t)lru_to_page(pages)->index << PAGE_SHIFT; #endif for (; nr_pages; --nr_pages) { struct page *page = lru_to_page(pages); -- 2.30.2