Bug 1824923 (CVE-2020-11725)

Summary: CVE-2020-11725 kernel: improper handling of private_size*count multiplication due to count=info->owner typo
Product: [Other] Security Response Reporter: Guilherme de Almeida Suckevicz <gsuckevi>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: acaringi, airlied, allarkin, bhu, blc, brdeoliv, bskeggs, dhoward, dvlasenk, esammons, fhrbata, hdegoede, hkrzesin, iboverma, ichavero, itamar, jarodwilson, jeremy, jforbes, jglisse, jlelli, john.j5live, jonathan, josef, jross, jshortt, jstancek, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, masami256, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, qzhao, rt-maint, rvrbovsk, steved, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in the Linux kernel. The Advanced Linux Sound Architecture subsystem's snd_ctl_elem_add mishandles the private_size*count multiplication when the addition of audio control elements happen leading to a denial of service.
Story Points: ---
Clone Of: Environment:
Last Closed: 2020-05-28 10:12:07 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1824925, 1834224, 1834225, 1834226, 1834227, 1834228    
Bug Blocks: 1824929    

Description Guilherme de Almeida Suckevicz 2020-04-16 16:46:38 UTC
snd_ctl_elem_add in sound/core/control.c in the Linux kernel through 5.6.3 has a count=info->owner typo, which is mishandled in the private_size*count multiplication.

References:
https://lore.kernel.org/alsa-devel/s5h4ktmlfpx.wl-tiwai@suse.de/
https://github.com/torvalds/linux/blob/3b2549a3740efb8af0150415737067d87e466c5b/sound/core/control.c#L1434-L1474

Comment 1 Guilherme de Almeida Suckevicz 2020-04-16 16:47:13 UTC
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1824925]

Comment 2 Justin M. Forbes 2020-04-16 18:40:22 UTC
Takashi seems to feel that this is invalid and the CVE should be disputed.

Comment 13 Petr Matousek 2020-05-28 10:16:27 UTC
Statement:

This CVE is being disputed as invalid (https://nvd.nist.gov/vuln/detail/CVE-2020-11725) based on the arguments presented in https://lore.kernel.org/alsa-devel/s5h4ktmlfpx.wl-tiwai@suse.de/ .