From 7b461610882c8baa64d56dade57cdbfb686739fa Mon Sep 17 00:00:00 2001 From: Gael Blivet Date: Fri, 17 Jul 2026 09:37:20 +0200 Subject: [PATCH] ksmbd: fix AsyncId zeroed before use in smb2_lock() cancel response release_async_work() zeroes work->async_id before the CANCELLED path calls smb2_send_interim_resp(work, STATUS_CANCELLED), which reads work->async_id to build the response's AsyncId field. The cancellation response for a cancelled blocked-lock request is sent with AsyncId=0 instead of the id the client received in the original STATUS_PENDING response for this request. Checked against every other release_async_work() call site in this file: smb2_read()/smb2_write() don't send a further async response afterward (their status goes out on the synchronous path instead), and smb2_notify()'s two async paths already transfer the id to a separate struct before releasing, so this reordering is scoped to smb2_lock() only. Send the STATUS_CANCELLED response while work->async_id is still valid, then release the async work afterward. Signed-off-by: Gael Blivet Assisted-by: Claude:claude-sonnet-5 Signed-off-by: Namjae Jeon --- fs/smb/server/smb2pdu.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 8d8567b73c43..18d1369b41f0 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -9319,22 +9319,25 @@ int smb2_lock(struct ksmbd_work *work) spin_unlock(&fp->f_lock); list_del(&smb_lock->llist); - release_async_work(work); - - if (work->state == KSMBD_WORK_ACTIVE) - goto retry; - - locks_free_lock(flock); if (work->state == KSMBD_WORK_CANCELLED) { rsp->hdr.Status = STATUS_CANCELLED; kfree(smb_lock); smb2_send_interim_resp(work, STATUS_CANCELLED); + release_async_work(work); + locks_free_lock(flock); work->send_no_response = 1; goto out; } + release_async_work(work); + + if (work->state == KSMBD_WORK_ACTIVE) + goto retry; + + locks_free_lock(flock); + rsp->hdr.Status = STATUS_RANGE_NOT_LOCKED; kfree(smb_lock);