kernfs_dir_next_pos() overlooks the situation that the dentry
corresponding to a given pos object has already been inactive. Hence,
when kernfs_dir_pos() returns the dentry with a hash value larger than
the original one, kernfs_dir_next_pos() returns the dentry next to the
one returned by kernfs_dir_pos(). As a result, the dentry returned by
kernfs_dir_pos() is skipped.
To fix this issue, try to find a next node only when the returned
object has a hash value equal to or smaller than the original one.
Signed-off-by: HATAYAMA Daisuke <[email protected]>
Suggested-by: Toshiyuki Okajima <[email protected]>
Cc: Eric W. Biederman <[email protected]>
---
fs/kernfs/dir.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 89d1dc1..8a2f49c 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -1622,7 +1622,7 @@ static int kernfs_dir_fop_release(struct inode *inode, struct file *filp)
struct kernfs_node *parent, ino_t ino, struct kernfs_node *pos)
{
pos = kernfs_dir_pos(ns, parent, ino, pos);
- if (pos) {
+ if (pos && pos->hash <= ino) {
do {
struct rb_node *node = rb_next(&pos->rb);
if (!node)
--
1.7.1
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Hatayama, Daisuke
> Sent: Saturday, May 19, 2018 12:43 AM
> To: '[email protected]' <[email protected]>
> Cc: Okajima, Toshiyuki/$B2,Eh(B $B<w9T(B <[email protected]>;
> [email protected]; '[email protected]'
> <[email protected]>
> Subject: [PATCH] kernfs: fix dentry unexpected skip
>
> kernfs_dir_next_pos() overlooks the situation that the dentry
> corresponding to a given pos object has already been inactive. Hence,
> when kernfs_dir_pos() returns the dentry with a hash value larger than
> the original one, kernfs_dir_next_pos() returns the dentry next to the
> one returned by kernfs_dir_pos(). As a result, the dentry returned by
> kernfs_dir_pos() is skipped.
>
> To fix this issue, try to find a next node only when the returned
> object has a hash value equal to or smaller than the original one.
>
> Signed-off-by: HATAYAMA Daisuke <[email protected]>
> Suggested-by: Toshiyuki Okajima <[email protected]>
> Cc: Eric W. Biederman <[email protected]>
> ---
> fs/kernfs/dir.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
> index 89d1dc1..8a2f49c 100644
> --- a/fs/kernfs/dir.c
> +++ b/fs/kernfs/dir.c
> @@ -1622,7 +1622,7 @@ static int kernfs_dir_fop_release(struct inode *inode,
> struct file *filp)
> struct kernfs_node *parent, ino_t ino, struct kernfs_node *pos)
> {
> pos = kernfs_dir_pos(ns, parent, ino, pos);
> - if (pos) {
> + if (pos && pos->hash <= ino) {
I found this condition still misses the case that the returend pos with
the same hash value but with different name is skipped. I'll post
v2 patch.
> do {
> struct rb_node *node = rb_next(&pos->rb);
> if (!node)
> --
> 1.7.1
>
>
>