Headline

CVE-2020-10690: use-after-free in cdev_put() when a PTP device is removed while it's chardev is open

There is a use-after-free in kernel versions before 5.5 due to a race condition between the release of ptp_clock and cdev while resource deallocation. When a (high privileged) process allocates a ptp device file (like /dev/ptpX) and voluntarily goes to sleep. During this time if the underlying device is removed, it can cause an exploitable condition as the process wakes up to terminate and clean all attached files. The system crashes due to the cdev structure being invalid (as already freed) which is pointed to by the inode.

4 years ago

CVE

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#vulnerability #linux #red_hat

Bug 1817141 (CVE-2020-10690) - CVE-2020-10690 kernel: use-after-free in cdev_put() when a PTP device is removed while it’s chardev is open

Summary: CVE-2020-10690 kernel: use-after-free in cdev_put() when a PTP device is remo…

Keywords:

Status:

CLOSED ERRATA

Alias:

CVE-2020-10690

Product:

Security Response

Classification:

Other

Component:

vulnerability

Sub Component:

Version:

unspecified

Hardware:

All

OS:

Linux

Priority:

low

Severity:

low

Target Milestone:

—

Assignee:

Red Hat Product Security

QA Contact:

Docs Contact:

URL:

Whiteboard:

Depends On:

1774657 1787568 1798395 1817354 1817355 1817356 1817357 1817358 1826223 1888688

Blocks:

1811167

TreeView+

depends on / blocked

Reported:

2020-03-25 16:45 UTC by Guilherme de Almeida Suckevicz

Modified:

2021-02-16 20:23 UTC (History)

CC List:

48 users (show)

Fixed In Version:

kernel 5.5

Doc Type:

If docs needed, set a value

Doc Text:

There is a use-after-free problem seen due to a race condition between the release of ptp_clock and cdev while resource deallocation. When a (high privileged) process allocates a ptp device file (like /dev/ptpX) and voluntarily goes to sleep. During this time if the underlying device is removed, it can cause an exploitable condition as the process wakes up to terminate and clean all attached files. The system crashes due to the cdev structure being invalid (as already freed) which is pointed to by the inode.

Clone Of:

Environment:

Last Closed:

2020-09-29 22:00:24 UTC

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