linux/ipc/compat_mq.c

139 lines
3.9 KiB
C
Raw Normal View History

/*
* 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 <linux/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);
}
COMPAT_SYSCALL_DEFINE4(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);
}
COMPAT_SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes,
const char __user *, u_msg_ptr,
compat_size_t, msg_len, unsigned int, msg_prio,
const struct compat_timespec __user *, u_abs_timeout)
{
struct timespec __user *u_ts;
compat: Get rid of (get|put)_compat_time(val|spec) We have two APIs for compatiblity timespec/val, with confusingly similar names. compat_(get|put)_time(val|spec) *do* handle the case where COMPAT_USE_64BIT_TIME is set, whereas (get|put)_compat_time(val|spec) do not. This is an accident waiting to happen. Clean it up by favoring the full-service version; the limited version is replaced with double-underscore versions static to kernel/compat.c. A common pattern is to convert a struct timespec to kernel format in an allocation on the user stack. Unfortunately it is open-coded in several places. Since this allocation isn't actually needed if COMPAT_USE_64BIT_TIME is true (since user format == kernel format) encapsulate that whole pattern into the function compat_convert_timespec(). An equivalent function should be written for struct timeval if it is needed in the future. Finally, get rid of compat_(get|put)_timeval_convert(): each was only used once, and the latter was not even doing what the function said (no conversion actually was being done.) Moving the conversion into compat_sys_settimeofday() itself makes the code much more similar to sys_settimeofday() itself. v3: Remove unused compat_convert_timeval(). v2: Drop bogus "const" in the destination argument for compat_convert_time*(). Cc: Mauro Carvalho Chehab <m.chehab@samsung.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-02 03:54:11 +01:00
if (compat_convert_timespec(&u_ts, u_abs_timeout))
return -EFAULT;
return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len,
msg_prio, u_ts);
}
COMPAT_SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes,
char __user *, u_msg_ptr,
compat_size_t, msg_len, unsigned int __user *, u_msg_prio,
const struct compat_timespec __user *, u_abs_timeout)
{
struct timespec __user *u_ts;
compat: Get rid of (get|put)_compat_time(val|spec) We have two APIs for compatiblity timespec/val, with confusingly similar names. compat_(get|put)_time(val|spec) *do* handle the case where COMPAT_USE_64BIT_TIME is set, whereas (get|put)_compat_time(val|spec) do not. This is an accident waiting to happen. Clean it up by favoring the full-service version; the limited version is replaced with double-underscore versions static to kernel/compat.c. A common pattern is to convert a struct timespec to kernel format in an allocation on the user stack. Unfortunately it is open-coded in several places. Since this allocation isn't actually needed if COMPAT_USE_64BIT_TIME is true (since user format == kernel format) encapsulate that whole pattern into the function compat_convert_timespec(). An equivalent function should be written for struct timeval if it is needed in the future. Finally, get rid of compat_(get|put)_timeval_convert(): each was only used once, and the latter was not even doing what the function said (no conversion actually was being done.) Moving the conversion into compat_sys_settimeofday() itself makes the code much more similar to sys_settimeofday() itself. v3: Remove unused compat_convert_timeval(). v2: Drop bogus "const" in the destination argument for compat_convert_time*(). Cc: Mauro Carvalho Chehab <m.chehab@samsung.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Tested-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-02 03:54:11 +01:00
if (compat_convert_timespec(&u_ts, u_abs_timeout))
return -EFAULT;
return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len,
u_msg_prio, u_ts);
}
COMPAT_SYSCALL_DEFINE2(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);
}
COMPAT_SYSCALL_DEFINE3(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;
}