Revision 8f182270dfec432e93fae14f9208a6b9af01009f authored by Lukasz Odzioba on 24 June 2016, 21:50:01 UTC, committed by Linus Torvalds on 25 June 2016, 00:23:52 UTC
Currently we can have compound pages held on per cpu pagevecs, which leads to a lot of memory unavailable for reclaim when needed. In the systems with hundreads of processors it can be GBs of memory. On of the way of reproducing the problem is to not call munmap explicitly on all mapped regions (i.e. after receiving SIGTERM). After that some pages (with THP enabled also huge pages) may end up on lru_add_pvec, example below. void main() { #pragma omp parallel { size_t size = 55 * 1000 * 1000; // smaller than MEM/CPUS void *p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS , -1, 0); if (p != MAP_FAILED) memset(p, 0, size); //munmap(p, size); // uncomment to make the problem go away } } When we run it with THP enabled it will leave significant amount of memory on lru_add_pvec. This memory will be not reclaimed if we hit OOM, so when we run above program in a loop: for i in `seq 100`; do ./a.out; done many processes (95% in my case) will be killed by OOM. The primary point of the LRU add cache is to save the zone lru_lock contention with a hope that more pages will belong to the same zone and so their addition can be batched. The huge page is already a form of batched addition (it will add 512 worth of memory in one go) so skipping the batching seems like a safer option when compared to a potential excess in the caching which can be quite large and much harder to fix because lru_add_drain_all is way to expensive and it is not really clear what would be a good moment to call it. Similarly we can reproduce the problem on lru_deactivate_pvec by adding: madvise(p, size, MADV_FREE); after memset. This patch flushes lru pvecs on compound page arrival making the problem less severe - after applying it kill rate of above example drops to 0%, due to reducing maximum amount of memory held on pvec from 28MB (with THP) to 56kB per CPU. Suggested-by: Michal Hocko <mhocko@suse.com> Link: http://lkml.kernel.org/r/1466180198-18854-1-git-send-email-lukasz.odzioba@intel.com Signed-off-by: Lukasz Odzioba <lukasz.odzioba@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Ming Li <mingli199x@qq.com> Cc: Minchan Kim <minchan@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent ea3a964
compat.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 <linux/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;
};
static inline int compat_ipc_parse_version(int *cmd)
{
#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
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 *uip)
{
int err;
__compat_uid_t u;
__compat_gid_t g;
err = __put_user(p->key, &uip->key);
SET_UID(u, p->uid);
err |= __put_user(u, &uip->uid);
SET_GID(g, p->gid);
err |= __put_user(g, &uip->gid);
SET_UID(u, p->cuid);
err |= __put_user(u, &uip->cuid);
SET_GID(g, p->cgid);
err |= __put_user(g, &uip->cgid);
err |= __put_user(p->mode, &uip->mode);
err |= __put_user(p->seq, &uip->seq);
return err;
}
static inline int get_compat_semid64_ds(struct semid64_ds *sem64,
struct compat_semid64_ds __user *up64)
{
if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
return -EFAULT;
return __get_compat_ipc64_perm(&sem64->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 *sem64,
struct compat_semid64_ds __user *up64)
{
int err;
if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
err = __put_compat_ipc64_perm(&sem64->sem_perm, &up64->sem_perm);
err |= __put_user(sem64->sem_otime, &up64->sem_otime);
err |= __put_user(sem64->sem_ctime, &up64->sem_ctime);
err |= __put_user(sem64->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)
{
unsigned long fourth;
int err, err2;
struct semid64_ds sem64;
struct semid64_ds __user *up64;
int version = compat_ipc_parse_version(&third);
memset(&sem64, 0, sizeof(sem64));
if ((third & (~IPC_64)) == SETVAL)
#ifdef __BIG_ENDIAN
fourth = (unsigned long)pad << 32;
#else
fourth = pad;
#endif
else
fourth = (unsigned long)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(sem64));
fourth = (unsigned long)up64;
err = sys_semctl(first, second, third, fourth);
if (err < 0)
break;
if (copy_from_user(&sem64, up64, sizeof(sem64)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_semid64_ds(&sem64, compat_ptr(pad));
else
err2 = put_compat_semid_ds(&sem64, compat_ptr(pad));
if (err2)
err = -EFAULT;
break;
case IPC_SET:
if (version == IPC_64)
err = get_compat_semid64_ds(&sem64, compat_ptr(pad));
else
err = get_compat_semid_ds(&sem64, compat_ptr(pad));
up64 = compat_alloc_user_space(sizeof(sem64));
if (copy_to_user(up64, &sem64, sizeof(sem64)))
err = -EFAULT;
if (err)
break;
fourth = (unsigned long)up64;
err = sys_semctl(first, second, third, fourth);
break;
default:
err = -EINVAL;
break;
}
return err;
}
static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
{
struct compat_msgbuf __user *msgp = dest;
size_t msgsz;
if (put_user(msg->m_type, &msgp->mtype))
return -EFAULT;
msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
if (store_msg(msgp->mtext, msg, msgsz))
return -EFAULT;
return msgsz;
}
#ifndef COMPAT_SHMLBA
#define COMPAT_SHMLBA SHMLBA
#endif
#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
u32, third, compat_uptr_t, ptr, u32, fifth)
{
int version;
u32 pad;
version = call >> 16; /* hack for backward compatibility */
call &= 0xffff;
switch (call) {
case SEMOP:
/* struct sembuf is the same on 32 and 64bit :)) */
return sys_semtimedop(first, compat_ptr(ptr), second, NULL);
case SEMTIMEDOP:
return compat_sys_semtimedop(first, compat_ptr(ptr), second,
compat_ptr(fifth));
case SEMGET:
return sys_semget(first, second, third);
case SEMCTL:
if (!ptr)
return -EINVAL;
if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
return -EFAULT;
return do_compat_semctl(first, second, third, pad);
case MSGSND: {
struct compat_msgbuf __user *up = compat_ptr(ptr);
compat_long_t type;
if (first < 0 || second < 0)
return -EINVAL;
if (get_user(type, &up->mtype))
return -EFAULT;
return do_msgsnd(first, type, up->mtext, second, third);
}
case MSGRCV: {
void __user *uptr = compat_ptr(ptr);
if (first < 0 || second < 0)
return -EINVAL;
if (!version) {
struct compat_ipc_kludge ipck;
if (!uptr)
return -EINVAL;
if (copy_from_user(&ipck, uptr, sizeof(ipck)))
return -EFAULT;
uptr = compat_ptr(ipck.msgp);
fifth = ipck.msgtyp;
}
return do_msgrcv(first, uptr, second, (s32)fifth, third,
compat_do_msg_fill);
}
case MSGGET:
return sys_msgget(first, second);
case MSGCTL:
return compat_sys_msgctl(first, second, compat_ptr(ptr));
case SHMAT: {
int err;
unsigned long raddr;
if (version == 1)
return -EINVAL;
err = do_shmat(first, compat_ptr(ptr), second, &raddr,
COMPAT_SHMLBA);
if (err < 0)
return err;
return put_user(raddr, (compat_ulong_t *)compat_ptr(third));
}
case SHMDT:
return sys_shmdt(compat_ptr(ptr));
case SHMGET:
return sys_shmget(first, (unsigned)second, third);
case SHMCTL:
return compat_sys_shmctl(first, second, compat_ptr(ptr));
}
return -ENOSYS;
}
#endif
COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg)
{
return do_compat_semctl(semid, semnum, cmd, arg);
}
COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
compat_ssize_t, msgsz, int, msgflg)
{
struct compat_msgbuf __user *up = compat_ptr(msgp);
compat_long_t mtype;
if (get_user(mtype, &up->mtype))
return -EFAULT;
return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg);
}
COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
compat_ssize_t, msgsz, compat_long_t, msgtyp, int, msgflg)
{
return do_msgrcv(msqid, compat_ptr(msgp), (ssize_t)msgsz, (long)msgtyp,
msgflg, compat_do_msg_fill);
}
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;
}
COMPAT_SYSCALL_DEFINE3(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;
}
COMPAT_SYSCALL_DEFINE3(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;
}
static inline int get_compat_shmid64_ds(struct shmid64_ds *sem64,
struct compat_shmid64_ds __user *up64)
{
if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
return -EFAULT;
return __get_compat_ipc64_perm(&sem64->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 *sem64,
struct compat_shmid64_ds __user *up64)
{
int err;
if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
return -EFAULT;
err = __put_compat_ipc64_perm(&sem64->shm_perm, &up64->shm_perm);
err |= __put_user(sem64->shm_atime, &up64->shm_atime);
err |= __put_user(sem64->shm_dtime, &up64->shm_dtime);
err |= __put_user(sem64->shm_ctime, &up64->shm_ctime);
err |= __put_user(sem64->shm_segsz, &up64->shm_segsz);
err |= __put_user(sem64->shm_nattch, &up64->shm_nattch);
err |= __put_user(sem64->shm_cpid, &up64->shm_cpid);
err |= __put_user(sem64->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;
}
COMPAT_SYSCALL_DEFINE3(shmctl, int, first, int, second, void __user *, uptr)
{
void __user *p;
struct shmid64_ds sem64;
struct shminfo64 smi;
int err, err2;
int version = compat_ipc_parse_version(&second);
memset(&sem64, 0, sizeof(sem64));
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(&sem64, uptr);
else
err = get_compat_shmid_ds(&sem64, uptr);
if (err)
break;
p = compat_alloc_user_space(sizeof(sem64));
if (copy_to_user(p, &sem64, sizeof(sem64)))
err = -EFAULT;
else
err = sys_shmctl(first, second, p);
break;
case IPC_STAT:
case SHM_STAT:
p = compat_alloc_user_space(sizeof(sem64));
err = sys_shmctl(first, second, p);
if (err < 0)
break;
if (copy_from_user(&sem64, p, sizeof(sem64)))
err2 = -EFAULT;
else if (version == IPC_64)
err2 = put_compat_shmid64_ds(&sem64, uptr);
else
err2 = put_compat_shmid_ds(&sem64, 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;
}
COMPAT_SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsems,
unsigned, nsops,
const struct compat_timespec __user *, timeout)
{
struct timespec __user *ts64;
if (compat_convert_timespec(&ts64, timeout))
return -EFAULT;
return sys_semtimedop(semid, tsems, nsops, ts64);
}
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