CVE-2021-47482

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Source
https://nvd.nist.gov/vuln/detail/CVE-2021-47482
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47482.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-47482
Related
Published
2024-05-22T09:15:10Z
Modified
2024-09-18T03:17:28.934421Z
Summary
[none]
Details

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

net: batman-adv: fix error handling

Syzbot reported ODEBUG warning in batadvncmeshfree(). The problem was in wrong error handling in batadvmesh_init().

Before this patch batadvmeshinit() was calling batadvmeshfree() in case of any batadv*init() calls failure. This approach may work well, when there is some kind of indicator, which can tell which parts of batadv are initialized; but there isn't any.

All written above lead to cleaning up uninitialized fields. Even if we hide ODEBUG warning by initializing batpriv->nc.work, syzbot was able to hit GPF in batadvncpurgepaths(), because hash pointer in still NULL. [1]

To fix these bugs we can unwind batadv*init() calls one by one. It is good approach for 2 reasons: 1) It fixes bugs on error handling path 2) It improves the performance, since we won't call unneeded batadv*free() functions.

So, this patch makes all batadv*init() clean up all allocated memory before returning with an error to no call correspoing batadv*free() and open-codes batadvmeshfree() with proper order to avoid touching uninitialized fields.

References

Affected packages

Debian:11 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.10.84-1

Affected versions

5.*

5.10.46-4
5.10.46-5
5.10.70-1~bpo10+1
5.10.70-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.15.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.15.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}