tree 44cc5c3c07e28d7b88b21733bcc192258f25bec4
parent bd756613f02baa088d2ebb476b40c1334ef97cf6
author Benjamin Block <bblock@linux.ibm.com> 1562101321 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1591165008 +0200

scsi: zfcp: fix request object use-after-free in send path causing wrong traces

[ Upstream commit 106d45f350c7cac876844dc685845cba4ffdb70b ]

When tracing instances where we open and close WKA ports, we also pass the
request-ID of the respective FSF command.

But after successfully sending the FSF command we must not use the
request-object anymore, as this might result in an use-after-free (see
"zfcp: fix request object use-after-free in send path causing seqno
errors" ).

To fix this add a new variable that caches the request-ID before sending
the request. This won't change during the hand-off to the FCP channel,
and so it's safe to trace this cached request-ID later, instead of using
the request object.

Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Fixes: d27a7cb91960 ("zfcp: trace on request for open and close of WKA port")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>