Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753700Ab1FKSwU (ORCPT ); Sat, 11 Jun 2011 14:52:20 -0400 Received: from mx1.vsecurity.com ([209.67.252.12]:55849 "EHLO mx1.vsecurity.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752276Ab1FKSwS (ORCPT ); Sat, 11 Jun 2011 14:52:18 -0400 Subject: [PATCH] alpha: fix several security issues From: Dan Rosenberg To: linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com Cc: security@kernel.org Content-Type: text/plain; charset="UTF-8" Date: Sat, 11 Jun 2011 14:52:05 -0400 Message-ID: <1307818325.1906.14.camel@dan> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2777 Lines: 84 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 --- arch/alpha/kernel/osf_sys.c | 11 +++++++---- 1 files changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 376f221..98fb16d 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -409,7 +409,7 @@ SYSCALL_DEFINE2(osf_getdomainname, char __user *, name, int, namelen) return -EFAULT; len = namelen; - if (namelen > 32) + if (len > 32) len = 32; down_read(&uts_sem); @@ -594,7 +594,7 @@ SYSCALL_DEFINE3(osf_sysinfo, int, command, char __user *, buf, long, count) 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; @@ -649,7 +649,7 @@ SYSCALL_DEFINE5(osf_getsysinfo, unsigned long, op, void __user *, buffer, 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; @@ -1008,6 +1008,7 @@ SYSCALL_DEFINE4(osf_wait4, pid_t, pid, int __user *, ustatus, int, options, { struct rusage r; long ret, err; + unsigned int status = 0; mm_segment_t old_fs; if (!ur) @@ -1016,13 +1017,15 @@ SYSCALL_DEFINE4(osf_wait4, pid_t, pid, int __user *, ustatus, int, options, 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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/