From b9f2e5763eeda2787c54b897a12d21560397549f Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Fri, 18 Oct 2024 04:33:10 +0900 Subject: [PATCH] nilfs2: fix kernel bug due to missing clearing of checked flag stable inclusion from stable-v6.6.60 commit f2f1fa446676c21edb777e6d2bc4fa8f956fab68 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB37AW CVE: CVE-2024-50230 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f2f1fa446676c21edb777e6d2bc4fa8f956fab68 -------------------------------- commit 41e192ad2779cae0102879612dfe46726e4396aa upstream. Syzbot reported that in directory operations after nilfs2 detects filesystem corruption and degrades to read-only, __block_write_begin_int(), which is called to prepare block writes, may fail the BUG_ON check for accesses exceeding the folio/page size, triggering a kernel bug. This was found to be because the "checked" flag of a page/folio was not cleared when it was discarded by nilfs2's own routine, which causes the sanity check of directory entries to be skipped when the directory page/folio is reloaded. So, fix that. This was necessary when the use of nilfs2's own page discard routine was applied to more than just metadata files. Link: https://lkml.kernel.org/r/20241017193359.5051-1-konishi.ryusuke@gmail.com Fixes: 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption") Signed-off-by: Ryusuke Konishi Reported-by: syzbot+d6ca2daf692c7a82f959@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d6ca2daf692c7a82f959 Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Wang Jinchao --- fs/nilfs2/page.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c index d1a148f0cae3..c4ca554bd73c 100644 --- a/fs/nilfs2/page.c +++ b/fs/nilfs2/page.c @@ -395,6 +395,7 @@ void nilfs_clear_dirty_page(struct page *page, bool silent) ClearPageUptodate(page); ClearPageMappedToDisk(page); + ClearPageChecked(page); if (page_has_buffers(page)) { struct buffer_head *bh, *head; -- Gitee