From: Rohith Surabattula rohiths@microsoft.com
commit 1254100030b3377e8302f9c75090ab191d73ee7c upstream.
Mid callback needs to be called only when valid data is read into pages.
These patches address a problem found during decryption offload: CIFS: VFS: trying to dequeue a deleted mid that could cause a refcount use after free: Workqueue: smb3decryptd smb2_decrypt_offload [cifs]
Signed-off-by: Rohith Surabattula rohiths@microsoft.com Reviewed-by: Pavel Shilovsky pshilov@microsoft.com CC: Stable stable@vger.kernel.org #5.4+ Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/cifs/smb2ops.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
--- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -4415,7 +4415,25 @@ static void smb2_decrypt_offload(struct dw->server->vals->read_rsp_size, dw->ppages, dw->npages, dw->len, true); - mid->callback(mid); + if (rc >= 0) { +#ifdef CONFIG_CIFS_STATS2 + mid->when_received = jiffies; +#endif + mid->callback(mid); + } else { + spin_lock(&GlobalMid_Lock); + if (dw->server->tcpStatus == CifsNeedReconnect) { + mid->mid_state = MID_RETRY_NEEDED; + spin_unlock(&GlobalMid_Lock); + mid->callback(mid); + } else { + mid->mid_state = MID_REQUEST_SUBMITTED; + mid->mid_flags &= ~(MID_DELETED); + list_add_tail(&mid->qhead, + &dw->server->pending_mid_q); + spin_unlock(&GlobalMid_Lock); + } + } cifs_mid_q_entry_release(mid); }