linux/ipc/compat.c
Will Deacon 079a96ae38 ipc: add COMPAT_SHMLBA support
If the SHMLBA definition for a native task differs from the definition for
a compat task, the do_shmat() function would need to handle both.

This patch introduces COMPAT_SHMLBA, which is used by the compat shmat
syscall when calling the ipc code and allows architectures such as AArch64
(where the native SHMLBA is 64k but the compat (AArch32) definition is
16k) to provide the correct semantics for compat IPC system calls.

Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:20 -07:00

750 lines
18 KiB
C

/*
* 32 bit compatibility code for System V IPC
*
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
* Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
* Copyright (C) 2000 VA Linux Co
* Copyright (C) 2000 Don Dugger <n0ano@valinux.com>
* Copyright (C) 2000 Hewlett-Packard Co.
* Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
* Copyright (C) 2000 Gerhard Tonn (ton@de.ibm.com)
* Copyright (C) 2000-2002 Andi Kleen, SuSE Labs (x86-64 port)
* Copyright (C) 2000 Silicon Graphics, Inc.
* Copyright (C) 2001 IBM
* Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Copyright (C) 2004 Arnd Bergmann (arnd@arndb.de)
*
* This code is collected from the versions for sparc64, mips64, s390x, ia64,
* ppc64 and x86_64, all of which are based on the original sparc64 version
* by Jakub Jelinek.
*
*/
#include <linux/compat.h>
#include <linux/errno.h>
#include <linux/highuid.h>
#include <linux/init.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/syscalls.h>
#include <linux/ptrace.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#include "util.h"
struct compat_msgbuf {
compat_long_t mtype;
char mtext[1];
};
struct compat_ipc_perm {
key_t key;
__compat_uid_t uid;
__compat_gid_t gid;
__compat_uid_t cuid;
__compat_gid_t cgid;
compat_mode_t mode;
unsigned short seq;
};
struct compat_semid_ds {
struct compat_ipc_perm sem_perm;
compat_time_t sem_otime;
compat_time_t sem_ctime;
compat_uptr_t sem_base;
compat_uptr_t sem_pending;
compat_uptr_t sem_pending_last;
compat_uptr_t undo;
unsigned short sem_nsems;
};
struct compat_msqid_ds {
struct compat_ipc_perm msg_perm;
compat_uptr_t msg_first;
compat_uptr_t msg_last;
compat_time_t msg_stime;
compat_time_t msg_rtime;
compat_time_t msg_ctime;
compat_ulong_t msg_lcbytes;
compat_ulong_t msg_lqbytes;
unsigned short msg_cbytes;
unsigned short msg_qnum;
unsigned short msg_qbytes;
compat_ipc_pid_t msg_lspid;
compat_ipc_pid_t msg_lrpid;
};
struct compat_shmid_ds {
struct compat_ipc_perm shm_perm;
int shm_segsz;
compat_time_t shm_atime;
compat_time_t shm_dtime;
compat_time_t shm_ctime;
compat_ipc_pid_t shm_cpid;
compat_ipc_pid_t shm_lpid;
unsigned short shm_nattch;
unsigned short shm_unused;
compat_uptr_t shm_unused2;
compat_uptr_t shm_unused3;
};
struct compat_ipc_kludge {
compat_uptr_t msgp;
compat_long_t msgtyp;
};
struct compat_shminfo64 {
compat_ulong_t shmmax;
compat_ulong_t shmmin;
compat_ulong_t shmmni;
compat_ulong_t shmseg;
compat_ulong_t shmall;
compat_ulong_t __unused1;
compat_ulong_t __unused2;
compat_ulong_t __unused3;
compat_ulong_t __unused4;
};
struct compat_shm_info {
compat_int_t used_ids;
compat_ulong_t shm_tot, shm_rss, shm_swp;
compat_ulong_t swap_attempts, swap_successes;
};
extern int sem_ctls[];
#define sc_semopm (sem_ctls[2])
static inline int compat_ipc_parse_version(int *cmd)
{
#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
int version = *cmd & IPC_64;
/* this is tricky: architectures that have support for the old
* ipc structures in 64 bit binaries need to have IPC_64 set
* in cmd, the others need to have it cleared */
#ifndef ipc_parse_version
*cmd |= IPC_64;
#else
*cmd &= ~IPC_64;
#endif
return version;
#else
/* With the asm-generic APIs, we always use the 64-bit versions. */
return IPC_64;
#endif
}
static inline int __get_compat_ipc64_perm(struct ipc64_perm *p64,
struct compat_ipc64_perm __user *up64)
{
int err;
err = __get_user(p64->uid, &up64->uid);
err |= __get_user(p64->gid, &up64->gid);
err |= __get_user(p64->mode, &up64->mode);
return err;
}
static inline int __get_compat_ipc_perm(struct ipc64_perm *p,
struct compat_ipc_perm __user *up)
{
int err;
err = __get_user(p->uid, &up->uid);
err |= __get_user(p->gid, &up->gid);
err |= __get_user(p->mode, &up->mode);
return err;
}
static inline int __put_compat_ipc64_perm(struct ipc64_perm *p64,
struct compat_ipc64_perm __user *up64)
{
int err;
err = __put_user(p64->key, &up64->key);
err |= __put_user(p64->uid, &up64->uid);
err |= __put_user(p64->gid, &up64->gid);
err |= __put_user(p64->cuid, &up64->cuid);
err |= __put_user(p64->cgid, &up64->cgid);
err |= __put_user(p64->mode, &up64->mode);
err |= __put_user(p64->seq, &up64->seq);
return err;
}
static inline int __put_compat_ipc_perm(struct ipc64_perm *p,
struct compat_ipc_perm __user *up)
{
int err;
__compat_uid_t u;
__compat_gid_t g;
err = __put_user(p->key, &up->key);
SET_UID(u, p->uid);
err |= __put_user(u, &up->uid);
SET_GID(g, p->gid);
err |= __put_user(g, &up->gid);
SET_UID(u, p->cuid);
err |= __put_user(u, &up->cuid);
SET_GID(g, p->cgid);
err |= __put_user(g, &up->cgid);
err |= __put_user(p->mode, &up->mode);
err |= __put_user(p->seq, &up->seq);
return err;
}
static inline int get_compat_semid64_ds(struct semid64_ds *s64,
struct compat_semid64_ds __user *up64)
{
if (!access_ok (VERIFY_READ, up64, sizeof(*up64)))
return -EFAULT;
return __get_compat_ipc64_perm(&s64->sem_perm, &up64->sem_perm);
}
static inline int get_compat_semid_ds(struct semid64_ds *s,
struct compat_semid_ds __user *up)
{
if (!access_ok (VERIFY_READ, up, sizeof(*up)))
return -EFAULT;
return __get_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
}
static inline int put_compat_semid64_ds(struct semid64_ds *s64,
struct compat_semid64_ds __user *up64)
{
int err;
if (!access_ok (VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
err = __put_compat_ipc64_perm(&s64->sem_perm, &up64->sem_perm);
err |= __put_user(s64->sem_otime, &up64->sem_otime);
err |= __put_user(s64->sem_ctime, &up64->sem_ctime);
err |= __put_user(s64->sem_nsems, &up64->sem_nsems);
return err;
}
static inline int put_compat_semid_ds(struct semid64_ds *s,
struct compat_semid_ds __user *up)
{
int err;
if (!access_ok (VERIFY_WRITE, up, sizeof(*up)))
return -EFAULT;
err = __put_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
err |= __put_user(s->sem_otime, &up->sem_otime);
err |= __put_user(s->sem_ctime, &up->sem_ctime);
err |= __put_user(s->sem_nsems, &up->sem_nsems);
return err;
}
static long do_compat_semctl(int first, int second, int third, u32 pad)
{
union semun fourth;
int err, err2;
struct semid64_ds s64;
struct semid64_ds __user *up64;
int version = compat_ipc_parse_version(&third);
memset(&s64, 0, sizeof(s64));
if ((third & (~IPC_64)) == SETVAL)
fourth.val = (int) pad;
else
fourth.__pad = compat_ptr(pad);
switch (third & (~IPC_64)) {
case IPC_INFO:
case IPC_RMID:
case SEM_INFO:
case GETVAL:
case GETPID:
case GETNCNT:
case GETZCNT:
case GETALL:
case SETVAL:
case SETALL:
err = sys_semctl(first, second, third, fourth);
break;
case IPC_STAT:
case SEM_STAT:
up64 = compat_alloc_user_space(sizeof(s64));
fourth.__pad = up64;
err = sys_semctl(first, second, third, fourth);
if (err < 0)
break;
if (copy_from_user(&s64, up64, sizeof(s64)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_semid64_ds(&s64, compat_ptr(pad));
else
err2 = put_compat_semid_ds(&s64, compat_ptr(pad));
if (err2)
err = -EFAULT;
break;
case IPC_SET:
if (version == IPC_64) {
err = get_compat_semid64_ds(&s64, compat_ptr(pad));
} else {
err = get_compat_semid_ds(&s64, compat_ptr(pad));
}
up64 = compat_alloc_user_space(sizeof(s64));
if (copy_to_user(up64, &s64, sizeof(s64)))
err = -EFAULT;
if (err)
break;
fourth.__pad = up64;
err = sys_semctl(first, second, third, fourth);
break;
default:
err = -EINVAL;
break;
}
return err;
}
#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
long compat_sys_semctl(int first, int second, int third, void __user *uptr)
{
u32 pad;
if (!uptr)
return -EINVAL;
if (get_user(pad, (u32 __user *) uptr))
return -EFAULT;
return do_compat_semctl(first, second, third, pad);
}
long compat_sys_msgsnd(int first, int second, int third, void __user *uptr)
{
struct compat_msgbuf __user *up = uptr;
long type;
if (first < 0)
return -EINVAL;
if (second < 0)
return -EINVAL;
if (get_user(type, &up->mtype))
return -EFAULT;
return do_msgsnd(first, type, up->mtext, second, third);
}
long compat_sys_msgrcv(int first, int second, int msgtyp, int third,
int version, void __user *uptr)
{
struct compat_msgbuf __user *up;
long type;
int err;
if (first < 0)
return -EINVAL;
if (second < 0)
return -EINVAL;
if (!version) {
struct compat_ipc_kludge ipck;
err = -EINVAL;
if (!uptr)
goto out;
err = -EFAULT;
if (copy_from_user (&ipck, uptr, sizeof(ipck)))
goto out;
uptr = compat_ptr(ipck.msgp);
msgtyp = ipck.msgtyp;
}
up = uptr;
err = do_msgrcv(first, &type, up->mtext, second, msgtyp, third);
if (err < 0)
goto out;
if (put_user(type, &up->mtype))
err = -EFAULT;
out:
return err;
}
#else
long compat_sys_semctl(int semid, int semnum, int cmd, int arg)
{
return do_compat_semctl(semid, semnum, cmd, arg);
}
long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp,
size_t msgsz, int msgflg)
{
compat_long_t mtype;
if (get_user(mtype, &msgp->mtype))
return -EFAULT;
return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
}
long compat_sys_msgrcv(int msqid, struct compat_msgbuf __user *msgp,
size_t msgsz, long msgtyp, int msgflg)
{
long err, mtype;
err = do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg);
if (err < 0)
goto out;
if (put_user(mtype, &msgp->mtype))
err = -EFAULT;
out:
return err;
}
#endif
static inline int get_compat_msqid64(struct msqid64_ds *m64,
struct compat_msqid64_ds __user *up64)
{
int err;
if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
return -EFAULT;
err = __get_compat_ipc64_perm(&m64->msg_perm, &up64->msg_perm);
err |= __get_user(m64->msg_qbytes, &up64->msg_qbytes);
return err;
}
static inline int get_compat_msqid(struct msqid64_ds *m,
struct compat_msqid_ds __user *up)
{
int err;
if (!access_ok(VERIFY_READ, up, sizeof(*up)))
return -EFAULT;
err = __get_compat_ipc_perm(&m->msg_perm, &up->msg_perm);
err |= __get_user(m->msg_qbytes, &up->msg_qbytes);
return err;
}
static inline int put_compat_msqid64_ds(struct msqid64_ds *m64,
struct compat_msqid64_ds __user *up64)
{
int err;
if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
err = __put_compat_ipc64_perm(&m64->msg_perm, &up64->msg_perm);
err |= __put_user(m64->msg_stime, &up64->msg_stime);
err |= __put_user(m64->msg_rtime, &up64->msg_rtime);
err |= __put_user(m64->msg_ctime, &up64->msg_ctime);
err |= __put_user(m64->msg_cbytes, &up64->msg_cbytes);
err |= __put_user(m64->msg_qnum, &up64->msg_qnum);
err |= __put_user(m64->msg_qbytes, &up64->msg_qbytes);
err |= __put_user(m64->msg_lspid, &up64->msg_lspid);
err |= __put_user(m64->msg_lrpid, &up64->msg_lrpid);
return err;
}
static inline int put_compat_msqid_ds(struct msqid64_ds *m,
struct compat_msqid_ds __user *up)
{
int err;
if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
return -EFAULT;
err = __put_compat_ipc_perm(&m->msg_perm, &up->msg_perm);
err |= __put_user(m->msg_stime, &up->msg_stime);
err |= __put_user(m->msg_rtime, &up->msg_rtime);
err |= __put_user(m->msg_ctime, &up->msg_ctime);
err |= __put_user(m->msg_cbytes, &up->msg_cbytes);
err |= __put_user(m->msg_qnum, &up->msg_qnum);
err |= __put_user(m->msg_qbytes, &up->msg_qbytes);
err |= __put_user(m->msg_lspid, &up->msg_lspid);
err |= __put_user(m->msg_lrpid, &up->msg_lrpid);
return err;
}
long compat_sys_msgctl(int first, int second, void __user *uptr)
{
int err, err2;
struct msqid64_ds m64;
int version = compat_ipc_parse_version(&second);
void __user *p;
memset(&m64, 0, sizeof(m64));
switch (second & (~IPC_64)) {
case IPC_INFO:
case IPC_RMID:
case MSG_INFO:
err = sys_msgctl(first, second, uptr);
break;
case IPC_SET:
if (version == IPC_64) {
err = get_compat_msqid64(&m64, uptr);
} else {
err = get_compat_msqid(&m64, uptr);
}
if (err)
break;
p = compat_alloc_user_space(sizeof(m64));
if (copy_to_user(p, &m64, sizeof(m64)))
err = -EFAULT;
else
err = sys_msgctl(first, second, p);
break;
case IPC_STAT:
case MSG_STAT:
p = compat_alloc_user_space(sizeof(m64));
err = sys_msgctl(first, second, p);
if (err < 0)
break;
if (copy_from_user(&m64, p, sizeof(m64)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_msqid64_ds(&m64, uptr);
else
err2 = put_compat_msqid_ds(&m64, uptr);
if (err2)
err = -EFAULT;
break;
default:
err = -EINVAL;
break;
}
return err;
}
#ifndef COMPAT_SHMLBA
#define COMPAT_SHMLBA SHMLBA
#endif
#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
long compat_sys_shmat(int first, int second, compat_uptr_t third, int version,
void __user *uptr)
{
int err;
unsigned long raddr;
compat_ulong_t __user *uaddr;
if (version == 1)
return -EINVAL;
err = do_shmat(first, uptr, second, &raddr, COMPAT_SHMLBA);
if (err < 0)
return err;
uaddr = compat_ptr(third);
return put_user(raddr, uaddr);
}
#else
long compat_sys_shmat(int shmid, compat_uptr_t shmaddr, int shmflg)
{
unsigned long ret;
long err;
err = do_shmat(shmid, compat_ptr(shmaddr), shmflg, &ret, COMPAT_SHMLBA);
if (err)
return err;
force_successful_syscall_return();
return (long)ret;
}
#endif
static inline int get_compat_shmid64_ds(struct shmid64_ds *s64,
struct compat_shmid64_ds __user *up64)
{
if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
return -EFAULT;
return __get_compat_ipc64_perm(&s64->shm_perm, &up64->shm_perm);
}
static inline int get_compat_shmid_ds(struct shmid64_ds *s,
struct compat_shmid_ds __user *up)
{
if (!access_ok(VERIFY_READ, up, sizeof(*up)))
return -EFAULT;
return __get_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
}
static inline int put_compat_shmid64_ds(struct shmid64_ds *s64,
struct compat_shmid64_ds __user *up64)
{
int err;
if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
err = __put_compat_ipc64_perm(&s64->shm_perm, &up64->shm_perm);
err |= __put_user(s64->shm_atime, &up64->shm_atime);
err |= __put_user(s64->shm_dtime, &up64->shm_dtime);
err |= __put_user(s64->shm_ctime, &up64->shm_ctime);
err |= __put_user(s64->shm_segsz, &up64->shm_segsz);
err |= __put_user(s64->shm_nattch, &up64->shm_nattch);
err |= __put_user(s64->shm_cpid, &up64->shm_cpid);
err |= __put_user(s64->shm_lpid, &up64->shm_lpid);
return err;
}
static inline int put_compat_shmid_ds(struct shmid64_ds *s,
struct compat_shmid_ds __user *up)
{
int err;
if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
return -EFAULT;
err = __put_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
err |= __put_user(s->shm_atime, &up->shm_atime);
err |= __put_user(s->shm_dtime, &up->shm_dtime);
err |= __put_user(s->shm_ctime, &up->shm_ctime);
err |= __put_user(s->shm_segsz, &up->shm_segsz);
err |= __put_user(s->shm_nattch, &up->shm_nattch);
err |= __put_user(s->shm_cpid, &up->shm_cpid);
err |= __put_user(s->shm_lpid, &up->shm_lpid);
return err;
}
static inline int put_compat_shminfo64(struct shminfo64 *smi,
struct compat_shminfo64 __user *up64)
{
int err;
if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
if (smi->shmmax > INT_MAX)
smi->shmmax = INT_MAX;
err = __put_user(smi->shmmax, &up64->shmmax);
err |= __put_user(smi->shmmin, &up64->shmmin);
err |= __put_user(smi->shmmni, &up64->shmmni);
err |= __put_user(smi->shmseg, &up64->shmseg);
err |= __put_user(smi->shmall, &up64->shmall);
return err;
}
static inline int put_compat_shminfo(struct shminfo64 *smi,
struct shminfo __user *up)
{
int err;
if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
return -EFAULT;
if (smi->shmmax > INT_MAX)
smi->shmmax = INT_MAX;
err = __put_user(smi->shmmax, &up->shmmax);
err |= __put_user(smi->shmmin, &up->shmmin);
err |= __put_user(smi->shmmni, &up->shmmni);
err |= __put_user(smi->shmseg, &up->shmseg);
err |= __put_user(smi->shmall, &up->shmall);
return err;
}
static inline int put_compat_shm_info(struct shm_info __user *ip,
struct compat_shm_info __user *uip)
{
int err;
struct shm_info si;
if (!access_ok(VERIFY_WRITE, uip, sizeof(*uip)) ||
copy_from_user(&si, ip, sizeof(si)))
return -EFAULT;
err = __put_user(si.used_ids, &uip->used_ids);
err |= __put_user(si.shm_tot, &uip->shm_tot);
err |= __put_user(si.shm_rss, &uip->shm_rss);
err |= __put_user(si.shm_swp, &uip->shm_swp);
err |= __put_user(si.swap_attempts, &uip->swap_attempts);
err |= __put_user(si.swap_successes, &uip->swap_successes);
return err;
}
long compat_sys_shmctl(int first, int second, void __user *uptr)
{
void __user *p;
struct shmid64_ds s64;
struct shminfo64 smi;
int err, err2;
int version = compat_ipc_parse_version(&second);
memset(&s64, 0, sizeof(s64));
switch (second & (~IPC_64)) {
case IPC_RMID:
case SHM_LOCK:
case SHM_UNLOCK:
err = sys_shmctl(first, second, uptr);
break;
case IPC_INFO:
p = compat_alloc_user_space(sizeof(smi));
err = sys_shmctl(first, second, p);
if (err < 0)
break;
if (copy_from_user(&smi, p, sizeof(smi)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_shminfo64(&smi, uptr);
else
err2 = put_compat_shminfo(&smi, uptr);
if (err2)
err = -EFAULT;
break;
case IPC_SET:
if (version == IPC_64) {
err = get_compat_shmid64_ds(&s64, uptr);
} else {
err = get_compat_shmid_ds(&s64, uptr);
}
if (err)
break;
p = compat_alloc_user_space(sizeof(s64));
if (copy_to_user(p, &s64, sizeof(s64)))
err = -EFAULT;
else
err = sys_shmctl(first, second, p);
break;
case IPC_STAT:
case SHM_STAT:
p = compat_alloc_user_space(sizeof(s64));
err = sys_shmctl(first, second, p);
if (err < 0)
break;
if (copy_from_user(&s64, p, sizeof(s64)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_shmid64_ds(&s64, uptr);
else
err2 = put_compat_shmid_ds(&s64, uptr);
if (err2)
err = -EFAULT;
break;
case SHM_INFO:
p = compat_alloc_user_space(sizeof(struct shm_info));
err = sys_shmctl(first, second, p);
if (err < 0)
break;
err2 = put_compat_shm_info(p, uptr);
if (err2)
err = -EFAULT;
break;
default:
err = -EINVAL;
break;
}
return err;
}
long compat_sys_semtimedop(int semid, struct sembuf __user *tsems,
unsigned nsops, const struct compat_timespec __user *timeout)
{
struct timespec __user *ts64 = NULL;
if (timeout) {
struct timespec ts;
ts64 = compat_alloc_user_space(sizeof(*ts64));
if (get_compat_timespec(&ts, timeout))
return -EFAULT;
if (copy_to_user(ts64, &ts, sizeof(ts)))
return -EFAULT;
}
return sys_semtimedop(semid, tsems, nsops, ts64);
}