On Wed, Apr 13, 2022 at 7:06 AM Ronnie Sahlberg <lsahlber@xxxxxxxxxx> wrote:
>
> On umount, cifs_sb->tlink_tree might contain entries that do not represent
> a valid tcon.
> Check the tcon for error before we dereference it.
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> ---
> fs/cifs/cifsfs.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index aba0783a8f09..25719b70564a 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -266,10 +266,11 @@ static void cifs_kill_sb(struct super_block *sb)
> * before we kill the sb.
> */
> if (cifs_sb->root) {
> - node = rb_first(root);
> - while (node != NULL) {
> + for(node = rb_first(root); node; node = rb_next(node)) {
> tlink = rb_entry(node, struct tcon_link, tl_rbnode);
> tcon = tlink_tcon(tlink);
> + if (IS_ERR(tcon))
> + continue;
> cfid = &tcon->crfid;
> mutex_lock(&cfid->fid_mutex);
> if (cfid->dentry) {
> @@ -277,7 +278,6 @@ static void cifs_kill_sb(struct super_block *sb)
> cfid->dentry = NULL;
> }
> mutex_unlock(&cfid->fid_mutex);
> - node = rb_next(node);
> }
>
> /* finally release root dentry */
> --
> 2.30.2
>
The changes look good to me.
Reviewed-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx>
Does this cover all the mount failure scenarios, Ronnie?
--
Regards,
Shyam
