SecurityFocus BUGTRAQ Mailing List: BugTraqLink Number One Link Number One Link
Number Two Link Number Two Link Number One Link Number One Link Number Two Link
Number Two
Entire Site Advisories Calendar Columnists Elsewhere
Guest Feature Infocus Library Links Mailing Lists
(all) -- BUGTRAQ -- FOCUS-IDS -- FOCUS-IH --
FOCUS-LINUX -- FOCUS-MS -- FOCUS-SUN -- FOCUS-VIRUS --
FORENSICS -- INCIDENTS -- PEN-TEST -- SEC JOBS -- SF
NEWS -- VULN-DEV News Products Services Tools Vulns
BUGTRAQ ARCHIVE
[ Message Index ] [ Thread Index ][ Reply ]
[ prev Msg by Date ][ next Msg by Date ]
To: BugTraq
Subject: FreeBSD Security Advisory
FreeBSD-SA-03:17.procfs
Date: Oct 3 2003 2:30PM
Author: FreeBSD Security Advisories
<security-advisories freebsd org>
Message-ID:
<200310031430.h93EUZHF045184@freefall.freebsd.org>
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
=============================================================================
FreeBSD-SA-03:17.procfs Security Advisory
The FreeBSD Project
Topic: kernel memory disclosure via procfs
Category: core
Module: sys
Announced: 2003-10-03
Credits: Joost Pol <joost pine nl>
Affects: All FreeBSD releases
Corrected: 2003-10-03 12:03:50 UTC (RELENG_4, 4.9-RC)
2003-10-03 13:02:17 UTC (RELENG_5_1, 5.1-RELEASE-p9)
2003-10-03 13:02:49 UTC (RELENG_5_0, 5.0-RELEASE-p17)
2003-10-03 13:03:44 UTC (RELENG_4_8, 4.8-RELEASE-p12)
2003-10-03 13:04:19 UTC (RELENG_4_7, 4.7-RELEASE-p22)
2003-10-03 13:05:05 UTC (RELENG_4_6, 4.6-RELEASE-p25)
2003-10-03 13:05:44 UTC (RELENG_4_5, 4.5-RELEASE-p36)
2003-10-03 13:06:32 UTC (RELENG_4_4, 4.4-RELEASE-p46)
2003-10-03 13:07:37 UTC (RELENG_4_3, 4.3-RELEASE-p42)
FreeBSD only: YES
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit
<URL:http://www.freebsd.org/security/>.
I. Background
The process file system, procfs(5), implements a view of the system
process table inside the file system. It is normally mounted on
/proc, and is required for the complete operation of programs such as
ps(1) and w(1).
The Linux process file system, linprocfs(5), emulates a subset of
Linux's process file system and is required for the complete operation
of some Linux binaries.
II. Problem Description
The procfs and linprocfs implementations use uiomove(9) and the
related `struct uio' in order to fulfill read and write requests.
Several cases were identified where members of `struct uio' were not
properly validated before being used. In particular, the `uio_offset'
member may be negative or extremely large, and was used to compute the
region of kernel memory to be returned to the user.
III. Impact
A malicious local user could arrange to use a negative or extremely
large offset when reading from a procfs ``file'', causing a system
crash, or causing the kernel to return a large portion of kernel
memory. Such memory might contain sensitive information, such as
portions of the file cache or terminal buffers. This information
might be directly useful, or it might be leveraged to obtain elevated
privileges in some way. For example, a terminal buffer might include
a user-entered password.
IV. Workaround
Unmount the procfs and linprocfs filesystems if they are mounted.
Execute the following command as root:
umount -a -t procfs,linprocfs
Also, remove or comment out any lines in fstab(5) that reference
`procfs' or `linprocfs', so that they will not be re-mounted at next
reboot.
V. Solution
1) Upgrade your vulnerable system to 4-STABLE, or to the
RELENG_5_1, RELENG_4_8, or RELENG_4_7 security branch dated
after the correction date.
2) To patch your present system:
a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.
[FreeBSD 4.3]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs43.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs43.patch.asc
[FreeBSD 4.4 and later 4.x]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs4x.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs4x.patch.asc
[FreeBSD 5.0]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs50.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs50.patch.asc
[FreeBSD 5.1]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs51.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:17/procfs51.patch.asc
b) Apply the patch.
# cd /usr/src
# patch < /path/to/patch
c) Recompile your kernel as described in
<URL:http://www.freebsd.org/handbook/kernelconfig.html>
and reboot the system.
VI. Correction details
The following list contains the revision numbers of each file that was
corrected in FreeBSD.
Branch Revision
Path
- -------------------------------------------------------------------------
RELENG_4
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.9
src/sys/kern/kern_subr.c 1.31.2.3
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.4
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.4
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.4
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.2.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.5
src/sys/sys/uio.h 1.11.2.2
RELENG_5_1
src/UPDATING 1.251.2.11
src/sys/conf/newvers.sh 1.50.2.11
src/sys/fs/procfs/procfs_dbregs.c 1.22.2.1
src/sys/fs/procfs/procfs_fpregs.c 1.28.2.1
src/sys/fs/procfs/procfs_regs.c 1.27.2.1
src/sys/fs/pseudofs/pseudofs_vnops.c 1.35.2.1
src/sys/kern/kern_subr.c 1.74.2.1
src/sys/sys/uio.h 1.27.2.1
RELENG_5_0
src/UPDATING 1.229.2.23
src/sys/conf/newvers.sh 1.48.2.18
src/sys/fs/procfs/procfs_dbregs.c 1.21.2.1
src/sys/fs/procfs/procfs_fpregs.c 1.27.2.1
src/sys/fs/procfs/procfs_regs.c 1.26.2.1
src/sys/fs/pseudofs/pseudofs_vnops.c 1.32.2.1
src/sys/kern/kern_subr.c 1.63.2.1
src/sys/sys/uio.h 1.23.2.1
RELENG_4_8
src/UPDATING 1.73.2.80.2.14
src/sys/conf/newvers.sh 1.44.2.29.2.13
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.8.10.1
src/sys/kern/kern_subr.c 1.31.2.2.6.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.3.8.1
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.3.8.1
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.3.8.1
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.14.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.4.8.1
src/sys/sys/uio.h 1.11.2.1.8.1
RELENG_4_7
src/UPDATING 1.73.2.74.2.25
src/sys/conf/newvers.sh 1.44.2.26.2.24
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.8.8.1
src/sys/kern/kern_subr.c 1.31.2.2.4.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.3.6.1
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.3.6.1
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.3.6.1
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.12.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.4.6.1
src/sys/sys/uio.h 1.11.2.1.6.1
RELENG_4_6
src/UPDATING 1.73.2.68.2.54
src/sys/conf/newvers.sh 1.44.2.23.2.42
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.8.6.1
src/sys/kern/kern_subr.c 1.31.2.2.2.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.3.4.1
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.3.4.1
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.3.4.1
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.10.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.4.4.1
src/sys/sys/uio.h 1.11.2.1.4.1
RELENG_4_5
src/UPDATING 1.73.2.50.2.53
src/sys/conf/newvers.sh 1.44.2.20.2.37
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.8.4.1
src/sys/kern/kern_subr.c 1.31.2.1.2.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.3.2.1
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.3.2.1
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.3.2.1
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.8.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.4.2.1
src/sys/sys/uio.h 1.11.2.1.2.1
RELENG_4_4
src/UPDATING 1.73.2.43.2.54
src/sys/conf/newvers.sh 1.44.2.17.2.45
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.8.2.1
src/sys/kern/kern_subr.c 1.31.6.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.2.2.2
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.2.2.2
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.2.2.2
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.6.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.3.4.2
src/sys/sys/uio.h 1.11.6.1
RELENG_4_3
src/UPDATING 1.73.2.28.2.41
src/sys/conf/newvers.sh 1.44.2.14.2.31
src/sys/i386/linux/linprocfs/linprocfs_misc.c 1.3.2.5.2.1
src/sys/kern/kern_subr.c 1.31.4.1
src/sys/miscfs/procfs/procfs_dbregs.c 1.4.2.1.2.2
src/sys/miscfs/procfs/procfs_fpregs.c 1.11.2.1.2.2
src/sys/miscfs/procfs/procfs_regs.c 1.10.2.1.2.2
src/sys/miscfs/procfs/procfs_rlimit.c 1.5.4.1
src/sys/miscfs/procfs/procfs_status.c 1.20.2.3.2.2
src/sys/sys/uio.h 1.11.4.1
- -------------------------------------------------------------------------
VII. References
<URL:http://www.pine.nl/press/pine-cert-20030902.txt>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (FreeBSD)
iD8DBQE/fYXyFdaIBMps37IRArbkAJ4qv/N215x61BW2NTyl6e4WY/DGLACgirQd
evgz6IOFh0L8fLRBHjbKO4A=
=Np7P
-----END PGP SIGNATURE-----
Want to link to this message? Use this URL:
<http://www.securityfocus.com/archive/1/340111>
Disclaimer, Terms & Conditions
About this List
Featured Lists:
ARIS Users
bugtraq
bugtraq-es
bugtraq-french NEW
bugtraq-jp
firewalls
focus-ids
focus-ih
focus-linux
focus-ms
focus-sun
focus-unix-other
focus-virus
forensics
forensics-es
honeypots
incidents
libnet
pen-test
secevents
secpapers
secprog
sectools
secureshell
security-basics
security-management NEW
securityjobs
vpn
vuln-dev
webappsec
Newsletters:
sf-news
ms-secnews
linux-secnews
[ more . . . ]
Privacy Statement
Copyright © 1999-2003 SecurityFocus