mirror of
https://github.com/torvalds/linux.git
synced 2026-10-09 12:06:03 +02:00
Linux kernel source tree
2dfa6688aa
Dan Carpenter kindly reported:
<quote>
The patch d27a7cb91960: "zfcp: trace on request for open and close of
WKA port" from Aug 10, 2016, leads to the following static checker
warning:
drivers/s390/scsi/zfcp_fsf.c:1615 zfcp_fsf_open_wka_port()
warn: 'req' was already freed.
drivers/s390/scsi/zfcp_fsf.c
1609 zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
1610 retval = zfcp_fsf_req_send(req);
1611 if (retval)
1612 zfcp_fsf_req_free(req);
^^^
Freed.
1613 out:
1614 spin_unlock_irq(&qdio->req_q_lock);
1615 if (req && !IS_ERR(req))
1616 zfcp_dbf_rec_run_wka("fsowp_1", wka_port, req->req_id);
^^^^^^^^^^^
Use after free.
1617 return retval;
1618 }
Same thing for zfcp_fsf_close_wka_port() as well.
</quote>
Rather than relying on req being NULL (or ERR_PTR) for all cases where
we don't want to trace or should not trace,
simply check retval which is unconditionally initialized with -EIO != 0
and it can only become 0 on successful retval = zfcp_fsf_req_send(req).
With that we can also remove the then again unnecessary unconditional
initialization of req which was introduced with that earlier commit.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.