https://www.openwall.com/lists/oss-security/2022/12/21/6

           * Products
               + Openwall GNU/*/Linux   server OS
               + Linux Kernel Runtime Guard
               + John the Ripper   password cracker
                   o Free & Open Source for any platform
                   o in the cloud
                   o Pro for Linux
                   o Pro for macOS
               + Wordlists   for password cracking
               + passwdqc   policy enforcement
                   o Free & Open Source for Unix
                   o Pro for Windows (Active Directory)
               + yescrypt   KDF & password hashing
               + yespower   Proof-of-Work (PoW)
               + crypt_blowfish   password hashing
               + phpass   ditto in PHP
               + tcb   better password shadowing
               + Pluggable Authentication Modules
Openwall       + scanlogd   port scan detector
               + popa3d   tiny POP3 daemon
               + blists   web interface to mailing lists
               + msulogin   single user mode login
               + php_mt_seed   mt_rand() cracker
           * Services
           * Publications
               + Articles
               + Presentations
           * Resources
               + Mailing lists
               + Community wiki
               + Source code repositories (GitHub)
               + Source code repositories (CVSweb)
               + File archive & mirrors
               + How to verify digital signatures
               + OVE IDs
           * What's new

Follow @Openwall on Twitter for new release announcements and other
news

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date: Wed, 21 Dec 2022 18:13:17 +0100
From: Dmitry Vyukov <dvyukov@...gle.com>
To: oss-security@...ts.openwall.com
Subject: [Linux] /proc/pid/stat parsing bugs

Hello,

This is not a single vulnerability, the list of affected software is
large, but it's not a security issue for all of it.

It occurred to me that most of the Linux procfs /proc/pid/stat and
/proc/pid/task/tid/stat parsing code out there is buggy. The fine
contains a set of numbers about the task:
https://man7.org/linux/man-pages/man5/proc.5.html

e.g. $ cat /proc/self/stat
1715376 (cat) R 1544883 1715376 1544883 34819 1715376 4194304 106 0 0
0 0 0 0 0 20 0 1 0 42505561 9207808 237 18446744073709551615
93955355631616 93955355651497 140737444557056 0 0 0 0 0 0 0 0 0 17 36
0 0 0 0 0 93955355667504 93955355669120 93955385581568 140737444559745
140737444559765 140737444559765 140737444564971 0

Most of the code splits it by space and takes an N-th field.
The problem is that the process name "(cat)" can contain spaces (and
brackets). Potentially some important software (containers/sandboxes)
can be tricked into getting wrong data, and I've seen cases close to
stack overflows (buffer for a fixed number of fields is allocated on
stack).

Some examples:
OpenJDK:
https://sourcegraph.com/github.com/openjdk/jdk/-/blob/src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c?L133-139
https://sourcegraph.com/github.com/openjdk/jdk8u/-/blob/jdk/src/solaris/native/sun/management/OperatingSystemImpl.c?L223-229

Ansible:
https://sourcegraph.com/github.com/ansible/ansible/-/blob/lib/ansible/modules/yum.py?L507-510

Libuv:
https://sourcegraph.com/github.com/libuv/libuv/-/blob/src/unix/linux.c?L674-701

bdwgc:
https://sourcegraph.com/github.com/mono/linux-packaging-mono/-/blob/external/bdwgc/os_dep.c?L1138-1155

But really most of the code that does it:
https://sourcegraph.com/search?q=context:global+/%5C%22%5C/proc%5C/.*%5C/stat%5C%22/

The only way to parse it is to do strrchr(')') first (fortunately it
contains just one unescaped string).

Thanks

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is
counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists
on Wikipedia and check out these guidelines on proper formatting of
your messages.