Bug 1399528 (CVE-2016-9644)

Summary: CVE-2016-9644 kernel: Incorrect fix for CVE-2016-9178
Product: [Other] Security Response Reporter: Andrej Nemec <anemec>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: agordeev, aquini, arm-mgr, bhu, dhoward, esammons, fhrbata, gansalmon, iboverma, ichavero, itamar, jforbes, jkacur, jkastner, joelsmith, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, nmurray, pholasek, plougher, rt-maint, rvrbovsk, vdronov, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Fixed In Version: Doc Type: If docs needed, set a value
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Clone Of: Environment:
Last Closed: 2016-11-29 09:17:27 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1415125    
Bug Blocks:    

Description Andrej Nemec 2016-11-29 09:16:01 UTC
The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux
kernel 4.4.22 through 4.4.28 contains extended asm statements that are
incompatible with the exception table, which allows local users to obtain root
access on non-SMEP platforms via a crafted application.  NOTE: this
vulnerability exists because of incorrect backporting of the CVE-2016-9178 patch
to older kernels.

Above refers to a new issue which affected some Linux stable lines, which backported 1c109fabbd51863475cd12ac206bdd249aee35af without also backporting 548acf19234dbda5a52d5a8e7e205af46e9da840.



Upstream patches:


Comment 2 Vladis Dronov 2017-01-20 10:51:47 UTC
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1415125]