CVE-2021-47482
See a problem?- 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
-
- https://git.kernel.org/stable/c/07533f1a673ce1126d0a72ef1e4b5eaaa3dd6d20
- https://git.kernel.org/stable/c/0c6b199f09be489c48622537a550787fc80aea73
- https://git.kernel.org/stable/c/6422e8471890273994fe8cc6d452b0dcd2c9483e
- https://git.kernel.org/stable/c/6f68cd634856f8ca93bafd623ba5357e0f648c68
- https://git.kernel.org/stable/c/a8f7359259dd5923adc6129284fdad12fc5db347
- https://git.kernel.org/stable/c/b0a2cd38553c77928ef1646ed1518486b1e70ae8
- https://git.kernel.org/stable/c/e50f957652190b5a88a8ebce7e5ab14ebd0d3f00
- https://git.kernel.org/stable/c/fbf150b16a3635634b7dfb7f229d8fcd643c6c51
- https://security-tracker.debian.org/tracker/CVE-2021-47482
Affected packages
Debian:11 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:12 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:13 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source