From 27cfa258951a465e3eae63ee1e715e902cd45578 Mon Sep 17 00:00:00 2001 From: Ye Bin Date: Wed, 15 Jun 2022 17:00:10 +0800 Subject: [PATCH 1/2] ext2: fix fs corruption when trying to remove a non-empty directory with IO error We got issue as follows: [home]# mount /dev/sdd test [home]# cd test [test]# ls dir1 lost+found [test]# rmdir dir1 ext2_empty_dir: inject fault [test]# ls lost+found [test]# cd .. [home]# umount test [home]# fsck.ext2 -fn /dev/sdd e2fsck 1.42.9 (28-Dec-2013) Pass 1: Checking inodes, blocks, and sizes Inode 4065, i_size is 0, should be 1024. Fix? no Pass 2: Checking directory structure Pass 3: Checking directory connectivity Unconnected directory inode 4065 (/???) Connect to /lost+found? no '..' in ... (4065) is / (2), should be (0). Fix? no Pass 4: Checking reference counts Inode 2 ref count is 3, should be 4. Fix? no Inode 4065 ref count is 2, should be 3. Fix? no Pass 5: Checking group summary information /dev/sdd: ********** WARNING: Filesystem still has errors ********** /dev/sdd: 14/128016 files (0.0% non-contiguous), 18477/512000 blocks Reason is same with commit 7aab5c84a0f6. We can't assume directory is empty when read directory entry failed. Link: https://lore.kernel.org/r/20220615090010.1544152-1-yebin10@huawei.com Signed-off-by: Ye Bin Signed-off-by: Jan Kara --- fs/ext2/dir.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c index 2c2f179b6977..43de293cef56 100644 --- a/fs/ext2/dir.c +++ b/fs/ext2/dir.c @@ -672,17 +672,14 @@ int ext2_empty_dir (struct inode * inode) void *page_addr = NULL; struct page *page = NULL; unsigned long i, npages = dir_pages(inode); - int dir_has_error = 0; for (i = 0; i < npages; i++) { char *kaddr; ext2_dirent * de; - page = ext2_get_page(inode, i, dir_has_error, &page_addr); + page = ext2_get_page(inode, i, 0, &page_addr); - if (IS_ERR(page)) { - dir_has_error = 1; - continue; - } + if (IS_ERR(page)) + goto not_empty; kaddr = page_addr; de = (ext2_dirent *)kaddr; From 4bca7e80b6455772b4bf3f536dcbc19aac424d6a Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 15 Jun 2022 15:22:29 +0200 Subject: [PATCH 2/2] init: Initialize noop_backing_dev_info early noop_backing_dev_info is used by superblocks of various pseudofilesystems such as kdevtmpfs. After commit 10e14073107d ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error") this broke because __mark_inode_dirty() started to access more fields from noop_backing_dev_info and this led to crashes inside locked_inode_to_wb_and_lock_list() called from __mark_inode_dirty(). Fix the problem by initializing noop_backing_dev_info before the filesystems get mounted. Fixes: 10e14073107d ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error") Reported-and-tested-by: Suzuki K Poulose Reported-and-tested-by: Alexandru Elisei Reported-and-tested-by: Guenter Roeck Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara --- drivers/base/init.c | 2 ++ include/linux/backing-dev.h | 2 ++ mm/backing-dev.c | 11 ++--------- 3 files changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/base/init.c b/drivers/base/init.c index d8d0fe687111..397eb9880cec 100644 --- a/drivers/base/init.c +++ b/drivers/base/init.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "base.h" @@ -20,6 +21,7 @@ void __init driver_init(void) { /* These are the core pieces */ + bdi_init(&noop_backing_dev_info); devtmpfs_init(); devices_init(); buses_init(); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 2bd073fa6bb5..d452071db572 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -119,6 +119,8 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); extern struct backing_dev_info noop_backing_dev_info; +int bdi_init(struct backing_dev_info *bdi); + /** * writeback_in_progress - determine whether there is writeback in progress * @wb: bdi_writeback of interest diff --git a/mm/backing-dev.c b/mm/backing-dev.c index ff60bd7d74e0..95550b8fa7fe 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -231,20 +231,13 @@ static __init int bdi_class_init(void) } postcore_initcall(bdi_class_init); -static int bdi_init(struct backing_dev_info *bdi); - static int __init default_bdi_init(void) { - int err; - bdi_wq = alloc_workqueue("writeback", WQ_MEM_RECLAIM | WQ_UNBOUND | WQ_SYSFS, 0); if (!bdi_wq) return -ENOMEM; - - err = bdi_init(&noop_backing_dev_info); - - return err; + return 0; } subsys_initcall(default_bdi_init); @@ -781,7 +774,7 @@ static void cgwb_remove_from_bdi_list(struct bdi_writeback *wb) #endif /* CONFIG_CGROUP_WRITEBACK */ -static int bdi_init(struct backing_dev_info *bdi) +int bdi_init(struct backing_dev_info *bdi) { int ret;