CVE-2021-47173: misc/uss720: fix memory leak in uss720_probe

CVE-2021-47173: misc/uss720: fix memory leak in uss720_probe

[Greg Kroah-Hartman]

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

misc/uss720: fix memory leak in uss720_probe

uss720_probe forgets to decrease the refcount of usbdev in uss720_probe.
Fix this by decreasing the refcount of usbdev by usb_put_dev.

BUG: memory leak
unreferenced object 0xffff888101113800 (size 2048):
  comm "kworker/0:1", pid 7, jiffies 4294956777 (age 28.870s)
  hex dump (first 32 bytes):
    ff ff ff ff 31 00 00 00 00 00 00 00 00 00 00 00  ....1...........
    00 00 00 00 00 00 00 00 00 00 00 00 03 00 00 00  ................
  backtrace:
    [<ffffffff82b8e822>] kmalloc include/linux/slab.h:554 [inline]
    [<ffffffff82b8e822>] kzalloc include/linux/slab.h:684 [inline]
    [<ffffffff82b8e822>] usb_alloc_dev+0x32/0x450 drivers/usb/core/usb.c:582
    [<ffffffff82b98441>] hub_port_connect drivers/usb/core/hub.c:5129 [inline]
    [<ffffffff82b98441>] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline]
    [<ffffffff82b98441>] port_event drivers/usb/core/hub.c:5509 [inline]
    [<ffffffff82b98441>] hub_event+0x1171/0x20c0 drivers/usb/core/hub.c:5591
    [<ffffffff81259229>] process_one_work+0x2c9/0x600 kernel/workqueue.c:2275
    [<ffffffff81259b19>] worker_thread+0x59/0x5d0 kernel/workqueue.c:2421
    [<ffffffff81261228>] kthread+0x178/0x1b0 kernel/kthread.c:292
    [<ffffffff8100227f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

The Linux kernel CVE team has assigned CVE-2021-47173 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 4.4.271 with commit 5f46b2410db2
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 4.9.271 with commit 7889c70e6173
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 4.14.235 with commit bcb30cc8f8be
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 4.19.193 with commit 386918878ce4
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 5.4.124 with commit 36b5ff1db1a4
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 5.10.42 with commit 5394ae9d8c79
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 5.12.9 with commit a3c3face38cb
	Issue introduced in 2.6.14 with commit 0f36163d3abe and fixed in 5.13 with commit dcb4b8ad6a44

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2021-47173
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/usb/misc/uss720.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/5f46b2410db2c8f26b8bb91b40deebf4ec184391
	https://git.kernel.org/stable/c/7889c70e6173ef358f3cd7578db127a489035a42
	https://git.kernel.org/stable/c/bcb30cc8f8befcbdbcf7a016e4dfd4747c54a364
	https://git.kernel.org/stable/c/386918878ce4cd676e4607233866e03c9399a46a
	https://git.kernel.org/stable/c/36b5ff1db1a4ef4fdbc2bae364344279f033ad88
	https://git.kernel.org/stable/c/5394ae9d8c7961dd93807fdf1b12a1dde96b0a55
	https://git.kernel.org/stable/c/a3c3face38cb49932c62adcc1289914f1c742096
	https://git.kernel.org/stable/c/dcb4b8ad6a448532d8b681b5d1a7036210b622de