CVE-2021-47482
Essential information
- Published
- 22/05/2024 09:15
- Modified
- 22/05/2024 12:46
- Author
- —
- Creator
- —
- CISA KEV
- No
- CWE
- —
- CVSS vector
- — — —
Description
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.
NVD status
- Status
- Awaiting Analysis — CVE has been recently published to the CVE List and has been received by the NVD.
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- NVD
- View on NVD