7

CVE-2022-48872

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

misc: fastrpc: Fix use-after-free race condition for maps

It is possible that in between calling fastrpc_map_get() until
map->fl->lock is taken in fastrpc_free_map(), another thread can call
fastrpc_map_lookup() and get a reference to a map that is about to be
deleted.

Rewrite fastrpc_map_get() to only increase the reference count of a map
if it's non-zero. Propagate this to callers so they can know if a map is
about to be deleted.

Fixes this warning:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 5 PID: 10100 at lib/refcount.c:25 refcount_warn_saturate
...
Call trace:
 refcount_warn_saturate
 [fastrpc_map_get inlined]
 [fastrpc_map_lookup inlined]
 fastrpc_map_create
 fastrpc_internal_invoke
 fastrpc_device_ioctl
 __arm64_sys_ioctl
 invoke_syscall
Data is provided by the National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 5.1 < 5.4.230
Linux ≫ Linux Kernel Version >= 5.5 < 5.10.165
Linux ≫ Linux Kernel Version >= 5.11 < 5.15.90
Linux ≫ Linux Kernel Version >= 5.16 < 6.2
Linux ≫ Linux Kernel Version6.2 Updaterc1
Linux ≫ Linux Kernel Version6.2 Updaterc2
Linux ≫ Linux Kernel Version6.2 Updaterc3
Linux ≫ Linux Kernel Version6.2 Updaterc4
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.02% 0.03
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 7 1 5.9
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.