From 5716a37020e08b3e93d2f4f7ed14ebf137029dd5 Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Wed, 19 May 2021 08:40:11 +1000
Subject: [PATCH] cifs: fix memory leak in smb2_copychunk_range
commit d201d7631ca170b038e7f8921120d05eec70d7c5 upstream.
When using smb2_copychunk_range() for large ranges we will
run through several iterations of a loop calling SMB2_ioctl()
but never actually free the returned buffer except for the final
iteration.
This leads to memory leaks everytime a large copychunk is requested.
Fixes: 9bf0c9cd4314 ("CIFS: Fix SMB2/SMB3 Copy offload support (refcopy) for large files")
Cc: <stable@vger.kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/cifs/smb2ops.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 67edd6e03f80..fffba1b1da2e 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -629,6 +629,8 @@ smb2_clone_range(const unsigned int xid,
cpu_to_le32(min_t(u32, len, tcon->max_bytes_chunk));
/* Request server copy to target from src identified by key */
+ kfree(retbuf);
+ retbuf = NULL;
rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
trgtfile->fid.volatile_fid, FSCTL_SRV_COPYCHUNK_WRITE,
true /* is_fsctl */, (char *)pcchunk,