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

net: batman-adv: fix error handling

Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was
in wrong error handling in batadv_mesh_init().

Before this patch batadv_mesh_init() was calling batadv_mesh_free() 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 bat_priv->nc.work, syzbot was able to hit
GPF in batadv_nc_purge_paths(), 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 batadv_mesh_free() with proper order to avoid touching
uninitialized fields.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 02 Apr 2025 15:30:00 +0000

Type Values Removed Values Added
First Time appeared Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc7:*:*:*:*:*:*
Vendors & Products Linux linux Kernel

Mon, 04 Nov 2024 12:15:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux kernel
CPEs cpe:2.3:a:linux:kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux kernel
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T07:12:02.779Z

Reserved: 2024-05-22T06:20:56.200Z

Link: CVE-2021-47482

cve-icon Vulnrichment

Updated: 2024-08-04T05:39:59.554Z

cve-icon NVD

Status : Analyzed

Published: 2024-05-22T09:15:10.150

Modified: 2025-04-02T15:09:19.797

Link: CVE-2021-47482

cve-icon Redhat

Severity : Low

Publid Date: 2024-05-22T00:00:00Z

Links: CVE-2021-47482 - Bugzilla

cve-icon OpenCVE Enrichment

No data.