2022-11-25 04:11:29

by Rock Li(李宏伟)

Subject: [PATCH] ocfs2: fix infinite loop for orphan entry list

Orphan file may be in the recover list already when the ip_next_orphan
is NULL (for example, orphan file is second tail elementof recover
list). In this scenario, the file could be added to the list twice
and infinite loop happened. So we need another pointer value here(EFAULT)
instead of NULL for the list tail element.

Signed-off-by: lihongweizz <[email protected]>
---
fs/ocfs2/journal.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 126671e..4620013 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -2207,7 +2207,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
enum ocfs2_orphan_reco_type orphan_reco_type)
{
int ret = 0;
- struct inode *inode = NULL;
+ struct inode *inode = ERR_PTR(-EFAULT);
struct inode *iter;
struct ocfs2_inode_info *oi;
struct buffer_head *di_bh = NULL;
@@ -2224,7 +2224,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
if (ret)
mlog_errno(ret);

- while (inode) {
+ while (!IS_ERR(inode)) {
oi = OCFS2_I(inode);
trace_ocfs2_recover_orphans_iput(
(unsigned long long)oi->ip_blkno);
--
1.8.3.1

2022-11-25 09:48:32

by Joseph Qi

Subject: Re: [PATCH] ocfs2: fix infinite loop for orphan entry list

On 11/25/22 11:41 AM, lihongweizz wrote:
> Orphan file may be in the recover list already when the ip_next_orphan
> is NULL (for example, orphan file is second tail elementof recover
> list). In this scenario, the file could be added to the list twice
> and infinite loop happened. So we need another pointer value here(EFAULT)
> instead of NULL for the list tail element.
>

Don't understand how it happens. Is this a real issue you encountered?
When queue orphans, it will bypass those already in recover list.

Thanks,
Joseph

> Signed-off-by: lihongweizz <[email protected]>
> ---
> fs/ocfs2/journal.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
> index 126671e..4620013 100644
> --- a/fs/ocfs2/journal.c
> +++ b/fs/ocfs2/journal.c
> @@ -2207,7 +2207,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
> enum ocfs2_orphan_reco_type orphan_reco_type)
> {
> int ret = 0;
> - struct inode *inode = NULL;
> + struct inode *inode = ERR_PTR(-EFAULT);
> struct inode *iter;
> struct ocfs2_inode_info *oi;
> struct buffer_head *di_bh = NULL;
> @@ -2224,7 +2224,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
> if (ret)
> mlog_errno(ret);
>
> - while (inode) {
> + while (!IS_ERR(inode)) {
> oi = OCFS2_I(inode);
> trace_ocfs2_recover_orphans_iput(
> (unsigned long long)oi->ip_blkno);