This is a note to let you know that I've just added the patch titled ksmbd: fix possible null-deref in smb_lazy_parent_lease_break_close to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ksmbd-fix-possible-null-deref-in-smb_lazy_parent_lea.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 07b448a447d2838c0014e19f1957f7f7c98ccc1a Author: Marios Makassikis <mmakassikis@xxxxxxxxxx> Date: Wed Mar 13 15:11:38 2024 +0100 ksmbd: fix possible null-deref in smb_lazy_parent_lease_break_close [ Upstream commit 5fb282ba4fef8985a5acf2b32681f2ec07732561 ] rcu_dereference can return NULL, so make sure we check against that. Signed-off-by: Marios Makassikis <mmakassikis@xxxxxxxxxx> Acked-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c index 7bdae2adad228..58bafe23ded9a 100644 --- a/fs/smb/server/oplock.c +++ b/fs/smb/server/oplock.c @@ -1152,7 +1152,7 @@ void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp) opinfo = rcu_dereference(fp->f_opinfo); rcu_read_unlock(); - if (!opinfo->is_lease || opinfo->o_lease->version != 2) + if (!opinfo || !opinfo->is_lease || opinfo->o_lease->version != 2) return; p_ci = ksmbd_inode_lookup_lock(fp->filp->f_path.dentry->d_parent);