From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757275Ab1HFAJj (ORCPT ); Fri, 5 Aug 2011 20:09:39 -0400 Received: from cantor2.suse.de ([195.135.220.15]:39236 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757239Ab1HFAJe (ORCPT ); Fri, 5 Aug 2011 20:09:34 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Aug 5 17:02:53 2011 Message-Id: <20110806000253.797609559@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 05 Aug 2011 17:02:19 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Dan Rosenberg , Richard Henderson , Ivan Kokshaysky , Matt Turner Subject: [49/55] alpha: fix several security issues In-Reply-To: <20110806000257.GA25498@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Dan Rosenberg commit 21c5977a836e399fc710ff2c5367845ed5c2527f upstream. Fix several security issues in Alpha-specific syscalls. Untested, but mostly trivial. 1. Signedness issue in osf_getdomainname allows copying out-of-bounds kernel memory to userland. 2. Signedness issue in osf_sysinfo allows copying large amounts of kernel memory to userland. 3. Typo (?) in osf_getsysinfo bounds minimum instead of maximum copy size, allowing copying large amounts of kernel memory to userland. 4. Usage of user pointer in osf_wait4 while under KERNEL_DS allows privilege escalation via writing return value of sys_wait4 to kernel memory. Signed-off-by: Dan Rosenberg Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/alpha/kernel/osf_sys.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -431,7 +431,7 @@ SYSCALL_DEFINE2(osf_getdomainname, char return -EFAULT; len = namelen; - if (namelen > 32) + if (len > 32) len = 32; down_read(&uts_sem); @@ -618,7 +618,7 @@ SYSCALL_DEFINE3(osf_sysinfo, int, comman down_read(&uts_sem); res = sysinfo_table[offset]; len = strlen(res)+1; - if (len > count) + if ((unsigned long)len > (unsigned long)count) len = count; if (copy_to_user(buf, res, len)) err = -EFAULT; @@ -673,7 +673,7 @@ SYSCALL_DEFINE5(osf_getsysinfo, unsigned return 1; case GSI_GET_HWRPB: - if (nbytes < sizeof(*hwrpb)) + if (nbytes > sizeof(*hwrpb)) return -EINVAL; if (copy_to_user(buffer, hwrpb, nbytes) != 0) return -EFAULT; @@ -1035,6 +1035,7 @@ SYSCALL_DEFINE4(osf_wait4, pid_t, pid, i { struct rusage r; long ret, err; + unsigned int status = 0; mm_segment_t old_fs; if (!ur) @@ -1043,13 +1044,15 @@ SYSCALL_DEFINE4(osf_wait4, pid_t, pid, i old_fs = get_fs(); set_fs (KERNEL_DS); - ret = sys_wait4(pid, ustatus, options, (struct rusage __user *) &r); + ret = sys_wait4(pid, (unsigned int __user *) &status, options, + (struct rusage __user *) &r); set_fs (old_fs); if (!access_ok(VERIFY_WRITE, ur, sizeof(*ur))) return -EFAULT; err = 0; + err |= put_user(status, ustatus); err |= __put_user(r.ru_utime.tv_sec, &ur->ru_utime.tv_sec); err |= __put_user(r.ru_utime.tv_usec, &ur->ru_utime.tv_usec); err |= __put_user(r.ru_stime.tv_sec, &ur->ru_stime.tv_sec);