[PATCH 7.0 23/76] smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()

7.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Stefan Metzmacher <[email protected]>

commit 27b7c3e916218b5eb2ee350211140e961bfc49be upstream.

smbd_send_batch_flush() already calls smbd_free_send_io(),
so we should not call it again after smbd_post_send()
moved it to the batch list.

Reported-by: Ruikai Peng <[email protected]>
Closes: https://lore.kernel.org/linux-cifs/CAFD3drNOSJ05y3A+jNXSDxW-2w09KHQ0DivhxQ_pcc7immVVOQ@mail.gmail.com/
Fixes: 21538121efe6 ("smb: client: make use of smbdirect_socket.send_io.bcredits")
Cc: [email protected]
Cc: Steve French <[email protected]>
Cc: Tom Talpey <[email protected]>
Cc: Long Li <[email protected]>
Cc: Ruikai Peng <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Acked-by: Paulo Alcantara (Red Hat) <[email protected]>
Acked-by: Namjae Jeon <[email protected]>
Signed-off-by: Stefan Metzmacher <[email protected]>
Tested-by: Ruikai Peng <[email protected]>
Signed-off-by: Steve French <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 fs/smb/client/smbdirect.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/fs/smb/client/smbdirect.c
+++ b/fs/smb/client/smbdirect.c
@@ -1551,17 +1551,25 @@ static int smbd_post_send_iter(struct sm
 
 	rc = smbd_post_send(sc, batch, request);
 	if (!rc) {
+		/*
+		 * From here request is moved to batch
+		 * and we should not free it explicitly.
+		 */
+
 		if (batch != &_batch)
 			return 0;
 
 		rc = smbd_send_batch_flush(sc, batch, true);
 		if (!rc)
 			return 0;
+
+		goto err_flush;
 	}
 
 err_dma:
 	smbd_free_send_io(request);
 
+err_flush:
 err_alloc:
 	atomic_inc(&sc->send_io.credits.count);
 	wake_up(&sc->send_io.credits.wait_queue);