From 0c9df7fb80360802f241428be7104f79d7c0f4ee Mon Sep 17 00:00:00 2001 From: Yunlong Song Date: Thu, 26 May 2016 19:40:29 +0800 Subject: [PATCH] f2fs: return the errno to the caller to avoid using a wrong page Commit aaf9607516ed38825268515ef4d773289a44f429 ("f2fs: check node page contents all the time") pointed out that "sometimes it was reported that its contents was missing", so it checks the page's mapping and contents. When "nid != nid_of_node(page)", ERR_PTR(-EIO) will be returned to the caller. However, commit e1c51b9f1df2f9efc2ec11488717e40cd12015f9 ("f2fs: clean up node page updating flow") moves "nid != nid_of_node(page)" test to "f2fs_bug_on(sbi, nid != nid_of_node(page))", this will return a wrong page to the caller when F2FS_CHECK_FS is off when "sometimes it was reported that its contents was missing" happens. This patch restores to check node page contents all the time, and returns the errno to make the caller known something is wrong and avoid to use the page. This patch also moves f2fs_bug_on to its proper location. Signed-off-by: Yunlong Song Signed-off-by: Jaegeuk Kim --- fs/f2fs/node.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 641d60392bff..16532b31dcd6 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1142,16 +1142,21 @@ repeat: lock_page(page); - if (unlikely(!PageUptodate(page))) { - f2fs_put_page(page, 1); - return ERR_PTR(-EIO); - } + if (unlikely(!PageUptodate(page))) + goto out_err; + if (unlikely(page->mapping != NODE_MAPPING(sbi))) { f2fs_put_page(page, 1); goto repeat; } page_hit: - f2fs_bug_on(sbi, nid != nid_of_node(page)); + if(unlikely(nid != nid_of_node(page))) { + f2fs_bug_on(sbi, 1); + ClearPageUptodate(page); +out_err: + f2fs_put_page(page, 1); + return ERR_PTR(-EIO); + } return page; } -- 2.20.1