mirror of
https://github.com/torvalds/linux.git
synced 2024-12-15 07:33:56 +00:00
03145beb45
This takes care of leaking uninitialized kernel stack memory to userspace from non-zeroed fields in structs in compat ipc functions. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
152 lines
4.1 KiB
C
152 lines
4.1 KiB
C
/*
|
|
* ipc/compat_mq.c
|
|
* 32 bit emulation for POSIX message queue system calls
|
|
*
|
|
* Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
|
* Author: Arnd Bergmann <arnd@arndb.de>
|
|
*/
|
|
|
|
#include <linux/compat.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mqueue.h>
|
|
#include <linux/syscalls.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
|
|
struct compat_mq_attr {
|
|
compat_long_t mq_flags; /* message queue flags */
|
|
compat_long_t mq_maxmsg; /* maximum number of messages */
|
|
compat_long_t mq_msgsize; /* maximum message size */
|
|
compat_long_t mq_curmsgs; /* number of messages currently queued */
|
|
compat_long_t __reserved[4]; /* ignored for input, zeroed for output */
|
|
};
|
|
|
|
static inline int get_compat_mq_attr(struct mq_attr *attr,
|
|
const struct compat_mq_attr __user *uattr)
|
|
{
|
|
if (!access_ok(VERIFY_READ, uattr, sizeof *uattr))
|
|
return -EFAULT;
|
|
|
|
return __get_user(attr->mq_flags, &uattr->mq_flags)
|
|
| __get_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
|
|
| __get_user(attr->mq_msgsize, &uattr->mq_msgsize)
|
|
| __get_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
|
|
}
|
|
|
|
static inline int put_compat_mq_attr(const struct mq_attr *attr,
|
|
struct compat_mq_attr __user *uattr)
|
|
{
|
|
if (clear_user(uattr, sizeof *uattr))
|
|
return -EFAULT;
|
|
|
|
return __put_user(attr->mq_flags, &uattr->mq_flags)
|
|
| __put_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
|
|
| __put_user(attr->mq_msgsize, &uattr->mq_msgsize)
|
|
| __put_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
|
|
}
|
|
|
|
asmlinkage long compat_sys_mq_open(const char __user *u_name,
|
|
int oflag, compat_mode_t mode,
|
|
struct compat_mq_attr __user *u_attr)
|
|
{
|
|
void __user *p = NULL;
|
|
if (u_attr && oflag & O_CREAT) {
|
|
struct mq_attr attr;
|
|
|
|
memset(&attr, 0, sizeof(attr));
|
|
|
|
p = compat_alloc_user_space(sizeof(attr));
|
|
if (get_compat_mq_attr(&attr, u_attr) ||
|
|
copy_to_user(p, &attr, sizeof(attr)))
|
|
return -EFAULT;
|
|
}
|
|
return sys_mq_open(u_name, oflag, mode, p);
|
|
}
|
|
|
|
static int compat_prepare_timeout(struct timespec __user * *p,
|
|
const struct compat_timespec __user *u)
|
|
{
|
|
struct timespec ts;
|
|
if (!u) {
|
|
*p = NULL;
|
|
return 0;
|
|
}
|
|
*p = compat_alloc_user_space(sizeof(ts));
|
|
if (get_compat_timespec(&ts, u) || copy_to_user(*p, &ts, sizeof(ts)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
asmlinkage long compat_sys_mq_timedsend(mqd_t mqdes,
|
|
const char __user *u_msg_ptr,
|
|
size_t msg_len, unsigned int msg_prio,
|
|
const struct compat_timespec __user *u_abs_timeout)
|
|
{
|
|
struct timespec __user *u_ts;
|
|
|
|
if (compat_prepare_timeout(&u_ts, u_abs_timeout))
|
|
return -EFAULT;
|
|
|
|
return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len,
|
|
msg_prio, u_ts);
|
|
}
|
|
|
|
asmlinkage ssize_t compat_sys_mq_timedreceive(mqd_t mqdes,
|
|
char __user *u_msg_ptr,
|
|
size_t msg_len, unsigned int __user *u_msg_prio,
|
|
const struct compat_timespec __user *u_abs_timeout)
|
|
{
|
|
struct timespec __user *u_ts;
|
|
if (compat_prepare_timeout(&u_ts, u_abs_timeout))
|
|
return -EFAULT;
|
|
|
|
return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len,
|
|
u_msg_prio, u_ts);
|
|
}
|
|
|
|
asmlinkage long compat_sys_mq_notify(mqd_t mqdes,
|
|
const struct compat_sigevent __user *u_notification)
|
|
{
|
|
struct sigevent __user *p = NULL;
|
|
if (u_notification) {
|
|
struct sigevent n;
|
|
p = compat_alloc_user_space(sizeof(*p));
|
|
if (get_compat_sigevent(&n, u_notification))
|
|
return -EFAULT;
|
|
if (n.sigev_notify == SIGEV_THREAD)
|
|
n.sigev_value.sival_ptr = compat_ptr(n.sigev_value.sival_int);
|
|
if (copy_to_user(p, &n, sizeof(*p)))
|
|
return -EFAULT;
|
|
}
|
|
return sys_mq_notify(mqdes, p);
|
|
}
|
|
|
|
asmlinkage long compat_sys_mq_getsetattr(mqd_t mqdes,
|
|
const struct compat_mq_attr __user *u_mqstat,
|
|
struct compat_mq_attr __user *u_omqstat)
|
|
{
|
|
struct mq_attr mqstat;
|
|
struct mq_attr __user *p = compat_alloc_user_space(2 * sizeof(*p));
|
|
long ret;
|
|
|
|
memset(&mqstat, 0, sizeof(mqstat));
|
|
|
|
if (u_mqstat) {
|
|
if (get_compat_mq_attr(&mqstat, u_mqstat) ||
|
|
copy_to_user(p, &mqstat, sizeof(mqstat)))
|
|
return -EFAULT;
|
|
}
|
|
ret = sys_mq_getsetattr(mqdes,
|
|
u_mqstat ? p : NULL,
|
|
u_omqstat ? p + 1 : NULL);
|
|
if (ret)
|
|
return ret;
|
|
if (u_omqstat) {
|
|
if (copy_from_user(&mqstat, p + 1, sizeof(mqstat)) ||
|
|
put_compat_mq_attr(&mqstat, u_omqstat))
|
|
return -EFAULT;
|
|
}
|
|
return 0;
|
|
}
|