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

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

From: Aurelien Aptel <aap...@suse.com>

commit d339adc12a4f885b572c5412e4869af8939db854 upstream.

The request buffers are freed right before copying the pointers.
Use the func args instead which are identical and still valid.

Simple reproducer (requires KASAN enabled) on a cifs mount:

echo foo > foo ; tail -f foo & rm foo

Cc: <sta...@vger.kernel.org> # 4.20
Fixes: 179e44d49c2f ("smb3: add tracepoint for sending lease break responses to 
server")
Signed-off-by: Aurelien Aptel <aap...@suse.com>
Signed-off-by: Steve French <stfre...@microsoft.com>
Reviewed-by: Paulo Alcantara <palcant...@suse.de>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 fs/cifs/smb2pdu.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -4339,8 +4339,8 @@ SMB2_lease_break(const unsigned int xid,
        rc = cifs_send_recv(xid, ses, &rqst, &resp_buf_type, flags, &rsp_iov);
        cifs_small_buf_release(req);
 
-       please_key_low = (__u64 *)req->LeaseKey;
-       please_key_high = (__u64 *)(req->LeaseKey+8);
+       please_key_low = (__u64 *)lease_key;
+       please_key_high = (__u64 *)(lease_key+8);
        if (rc) {
                cifs_stats_fail_inc(tcon, SMB2_OPLOCK_BREAK_HE);
                trace_smb3_lease_err(le32_to_cpu(lease_state), tcon->tid,


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