Bug 1677778 (CVE-2019-10140) - CVE-2019-10140 kernel: overlayfs: NULL pointer dereference in ovl_posix_acl_create function in fs/overlayfs/dir.c
Summary: CVE-2019-10140 kernel: overlayfs: NULL pointer dereference in ovl_posix_acl_c...
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2019-10140
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1729240 1677705 1685356 1685357 1696289 1696290 1696291 1696292 1726955
Blocks: 1677780
TreeView+ depends on / blocked
 
Reported: 2019-02-15 20:49 UTC by Laura Pardo
Modified: 2021-10-25 09:51 UTC (History)
49 users (show)

Fixed In Version:
Doc Type: If docs needed, set a value
Doc Text:
A vulnerability was found in Linux kernel's implementation of overlayfs. An attacker with local access can create a denial of service situation via NULL pointer dereference in ovl_posix_acl_create function in fs/overlayfs/dir.c. This can allow attackers with ability to create directories on overlayfs to crash the kernel creating a denial of service (DOS).
Clone Of:
Environment:
Last Closed: 2021-10-25 09:51:27 UTC
Embargoed:

Attachments (Terms of Use)
Fix for flaw. (374 bytes, patch)
2019-08-15 07:14 UTC, Wade Mealing 		no flags Details | Diff
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Description Laura Pardo 2019-02-15 20:49:33 UTC 
A vulnerability was found in Linux Kernels implementation of overlayfs. An attacker with local access can create a denial of service situation via NULL  pointer dereference in ovl_posix_acl_create function in fs/overlayfs/dir.c. The ovl_create function can return a positive number leading to a null pointer derference of path in may_open.

This can allow attackers with ability to create directories on overlayfs to crash the kernel creating a Denial Of Service (DOS).

This flaw likely only affects Red Hat Enterprise Linux 7 based products as this issue was created by by human-error in the backporting process.


References:
https://bugzilla.redhat.com/show_bug.cgi?id=1677705

Proposed fix:
https://bugzilla.redhat.com/show_bug.cgi?id=1677778
Comment 5 Laura Pardo 2019-05-24 18:21:02 UTC 
Acknowledgments:

Name: Vasily Averin (Virtuozzo)
Comment 10 Wade Mealing 2019-08-15 03:51:05 UTC 
Mitigation: 

Some systems may wish to use device-mapper as an alternative to overlayfs.  This does not remove the flaw if overlayfs module is still in use.
Comment 11 Wade Mealing 2019-08-15 07:14:11 UTC 
Created attachment 1604006 [details]
Fix for flaw.
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