[thirdparty/glibc.git] / sysdeps / unix / sysv / linux / shmctl.c

/* Copyright (C) 1995-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <sys/shm.h>
#include <stdarg.h>
#include <ipc_priv.h>
#include <sysdep.h>
#include <shlib-compat.h>
#include <errno.h>
#include <linux/posix_types.h>  /* For __kernel_mode_t.  */

/* POSIX states ipc_perm mode should have type of mode_t.  */
_Static_assert (sizeof ((struct shmid_ds){0}.shm_perm.mode)
		== sizeof (mode_t),
		"sizeof (shmid_ds.shm_perm.mode) != sizeof (mode_t)");

#if __IPC_TIME64 == 0
typedef struct shmid_ds shmctl_arg_t;
#else
# include <struct_kernel_shmid64_ds.h>

static void
shmid64_to_kshmid64 (const struct __shmid64_ds *shmid64,
		     struct kernel_shmid64_ds *kshmid)
{
  kshmid->shm_perm       = shmid64->shm_perm;
  kshmid->shm_segsz      = shmid64->shm_segsz;
  kshmid->shm_atime      = shmid64->shm_atime;
  kshmid->shm_atime_high = shmid64->shm_atime >> 32;
  kshmid->shm_dtime      = shmid64->shm_dtime;
  kshmid->shm_dtime_high = shmid64->shm_dtime >> 32;
  kshmid->shm_ctime      = shmid64->shm_ctime;
  kshmid->shm_ctime_high = shmid64->shm_ctime >> 32;
  kshmid->shm_cpid       = shmid64->shm_cpid;
  kshmid->shm_lpid       = shmid64->shm_lpid;
  kshmid->shm_nattch     = shmid64->shm_nattch;
}

static void
kshmid64_to_shmid64 (const struct kernel_shmid64_ds *kshmid,
		     struct __shmid64_ds *shmid64)
{
  shmid64->shm_perm   = kshmid->shm_perm;
  shmid64->shm_segsz  = kshmid->shm_segsz;
  shmid64->shm_atime  = kshmid->shm_atime
		        | ((__time64_t) kshmid->shm_atime_high << 32);
  shmid64->shm_dtime  = kshmid->shm_dtime
		        | ((__time64_t) kshmid->shm_dtime_high << 32);
  shmid64->shm_ctime  = kshmid->shm_ctime
		        | ((__time64_t) kshmid->shm_ctime_high << 32);
  shmid64->shm_cpid   = kshmid->shm_cpid;
  shmid64->shm_lpid   = kshmid->shm_lpid;
  shmid64->shm_nattch = kshmid->shm_nattch;
}

typedef struct kernel_shmid64_ds shmctl_arg_t;
#endif

static int
shmctl_syscall (int shmid, int cmd, shmctl_arg_t *buf)
{
#ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
  return INLINE_SYSCALL_CALL (shmctl, shmid, cmd | __IPC_64, buf);
#else
  return INLINE_SYSCALL_CALL (ipc, IPCOP_shmctl, shmid, cmd | __IPC_64, 0,
			      buf);
#endif
}

/* Provide operations to control over shared memory segments.  */
int
__shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
{
#if __IPC_TIME64
  struct kernel_shmid64_ds kshmid, *arg = NULL;
#else
  shmctl_arg_t *arg;
#endif

  switch (cmd)
    {
    case IPC_RMID:
    case SHM_LOCK:
    case SHM_UNLOCK:
      arg = NULL;
      break;

    case IPC_SET:
    case IPC_STAT:
    case SHM_STAT:
    case SHM_STAT_ANY:
#if __IPC_TIME64
      if (buf != NULL)
	{
	  shmid64_to_kshmid64 (buf, &kshmid);
	  arg = &kshmid;
	}
# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
      if (cmd == IPC_SET)
        arg->shm_perm.mode *= 0x10000U;
# endif
#else
      arg = buf;
#endif
      break;

    case IPC_INFO:
    case SHM_INFO:
      /* This is a Linux extension where kernel expects either a
	 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO).  */
      arg = (__typeof__ (arg)) buf;
      break;

    default:
      __set_errno (EINVAL);
      return -1;
    }


  int ret = shmctl_syscall (shmid, cmd, arg);
  if (ret < 0)
    return ret;

  switch (cmd)
    {
      case IPC_STAT:
      case SHM_STAT:
      case SHM_STAT_ANY:
#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
        arg->shm_perm.mode >>= 16;
#else
      /* Old Linux kernel versions might not clear the mode padding.  */
      if (sizeof ((struct shmid_ds){0}.shm_perm.mode)
	  != sizeof (__kernel_mode_t))
	arg->shm_perm.mode &= 0xFFFF;
#endif

#if __IPC_TIME64
      kshmid64_to_shmid64 (arg, buf);
#endif
    }

  return ret;
}
#if __TIMESIZE != 64
libc_hidden_def (__shmctl64)

static void
shmid_to_shmid64 (struct __shmid64_ds *shm64, const struct shmid_ds *shm)
{
  shm64->shm_perm   = shm->shm_perm;
  shm64->shm_segsz  = shm->shm_segsz;
  shm64->shm_atime  = shm->shm_atime
		      | ((__time64_t) shm->__shm_atime_high << 32);
  shm64->shm_dtime  = shm->shm_dtime
		      | ((__time64_t) shm->__shm_dtime_high << 32);
  shm64->shm_ctime  = shm->shm_ctime
		      | ((__time64_t) shm->__shm_ctime_high << 32);
  shm64->shm_cpid   = shm->shm_cpid;
  shm64->shm_lpid   = shm->shm_lpid;
  shm64->shm_nattch = shm->shm_nattch;
}

static void
shmid64_to_shmid (struct shmid_ds *shm, const struct __shmid64_ds *shm64)
{
  shm->shm_perm         = shm64->shm_perm;
  shm->shm_segsz        = shm64->shm_segsz;
  shm->shm_atime        = shm64->shm_atime;
  shm->__shm_atime_high = 0;
  shm->shm_dtime        = shm64->shm_dtime;
  shm->__shm_dtime_high = 0;
  shm->shm_ctime        = shm64->shm_ctime;
  shm->__shm_ctime_high = 0;
  shm->shm_cpid         = shm64->shm_cpid;
  shm->shm_lpid         = shm64->shm_lpid;
  shm->shm_nattch       = shm64->shm_nattch;
}

int
__shmctl (int shmid, int cmd, struct shmid_ds *buf)
{
  struct __shmid64_ds shmid64, *buf64 = NULL;
  if (buf != NULL)
    {
      /* This is a Linux extension where kernel expects either a
	 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO).  */
      if (cmd == IPC_INFO || cmd == SHM_INFO)
	buf64 = (struct __shmid64_ds *) buf;
      else
	{
	  shmid_to_shmid64 (&shmid64, buf);
	  buf64 = &shmid64;
	}
    }

  int ret = __shmctl64 (shmid, cmd, buf64);
  if (ret < 0)
    return ret;

  switch (cmd)
    {
      case IPC_STAT:
      case SHM_STAT:
      case SHM_STAT_ANY:
	shmid64_to_shmid (buf, buf64);
    }

  return ret;
}
#endif

#ifndef DEFAULT_VERSION
# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T
#  define DEFAULT_VERSION GLIBC_2_2
# else
#  define DEFAULT_VERSION GLIBC_2_31
# endif
#endif

versioned_symbol (libc, __shmctl, shmctl, DEFAULT_VERSION);

#if defined __ASSUME_SYSVIPC_BROKEN_MODE_T \
    && SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_31)
int
attribute_compat_text_section
__shmctl_mode16 (int shmid, int cmd, struct shmid_ds *buf)
{
  return shmctl_syscall (shmid, cmd, (shmctl_arg_t *) buf);
}
compat_symbol (libc, __shmctl_mode16, shmctl, GLIBC_2_2);
#endif

#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)
struct __old_shmid_ds
{
  struct __old_ipc_perm shm_perm;	/* operation permission struct */
  int shm_segsz;			/* size of segment in bytes */
  __time_t shm_atime;			/* time of last shmat() */
  __time_t shm_dtime;			/* time of last shmdt() */
  __time_t shm_ctime;			/* time of last change by shmctl() */
  __ipc_pid_t shm_cpid;			/* pid of creator */
  __ipc_pid_t shm_lpid;			/* pid of last shmop */
  unsigned short int shm_nattch;	/* number of current attaches */
  unsigned short int __shm_npages;	/* size of segment (pages) */
  unsigned long int *__shm_pages;	/* array of ptrs to frames -> SHMMAX */
  struct vm_area_struct *__attaches;	/* descriptors for attaches */
};

int
attribute_compat_text_section
__old_shmctl (int shmid, int cmd, struct __old_shmid_ds *buf)
{
#if defined __ASSUME_DIRECT_SYSVIPC_SYSCALLS \
    && !defined __ASSUME_SYSVIPC_DEFAULT_IPC_64
  /* For architecture that have wire-up shmctl but also have __IPC_64 to a
     value different than default (0x0), it means the compat symbol used the
     __NR_ipc syscall.  */
  return INLINE_SYSCALL_CALL (shmctl, shmid, cmd, buf);
#else
  return INLINE_SYSCALL_CALL (ipc, IPCOP_shmctl, shmid, cmd, 0, buf);
#endif
}
compat_symbol (libc, __old_shmctl, shmctl, GLIBC_2_0);
#endif
Commit	Line	Data
2b778ceb	1	/* Copyright (C) 1995-2021 Free Software Foundation, Inc.
3e5f5557 UD	2	This file is part of the GNU C Library.
3e5f5557 UD	3	Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
28f540f4	4
3e5f5557	5	The GNU C Library is free software; you can redistribute it and/or
41bdb6e2 AJ	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
28f540f4	9
3e5f5557 UD	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
41bdb6e2	13	Lesser General Public License for more details.
28f540f4	14
41bdb6e2	15	You should have received a copy of the GNU Lesser General Public
59ba27a6	16	License along with the GNU C Library; if not, see
5a82c748	17	<https://www.gnu.org/licenses/>. */
28f540f4	18
d2f5be2a	19	#include <sys/shm.h>
e01f79e4	20	#include <stdarg.h>
973209d8	21	#include <ipc_priv.h>
e9dcb080	22	#include <sysdep.h>
b5567b2a	23	#include <shlib-compat.h>
e01f79e4	24	#include <errno.h>
60f071f4	25	#include <linux/posix_types.h> /* For __kernel_mode_t. */
e01f79e4	26
ffd178c6 AZ	27	/* POSIX states ipc_perm mode should have type of mode_t. */
	28	_Static_assert (sizeof ((struct shmid_ds){0}.shm_perm.mode)
	29	== sizeof (mode_t),
	30	"sizeof (shmid_ds.shm_perm.mode) != sizeof (mode_t)");
	31
	32	#if __IPC_TIME64 == 0
	33	typedef struct shmid_ds shmctl_arg_t;
	34	#else
	35	# include <struct_kernel_shmid64_ds.h>
	36
	37	static void
	38	shmid64_to_kshmid64 (const struct __shmid64_ds *shmid64,
	39	struct kernel_shmid64_ds *kshmid)
	40	{
	41	kshmid->shm_perm = shmid64->shm_perm;
	42	kshmid->shm_segsz = shmid64->shm_segsz;
	43	kshmid->shm_atime = shmid64->shm_atime;
	44	kshmid->shm_atime_high = shmid64->shm_atime >> 32;
	45	kshmid->shm_dtime = shmid64->shm_dtime;
	46	kshmid->shm_dtime_high = shmid64->shm_dtime >> 32;
	47	kshmid->shm_ctime = shmid64->shm_ctime;
	48	kshmid->shm_ctime_high = shmid64->shm_ctime >> 32;
	49	kshmid->shm_cpid = shmid64->shm_cpid;
	50	kshmid->shm_lpid = shmid64->shm_lpid;
	51	kshmid->shm_nattch = shmid64->shm_nattch;
	52	}
	53
	54	static void
	55	kshmid64_to_shmid64 (const struct kernel_shmid64_ds *kshmid,
	56	struct __shmid64_ds *shmid64)
	57	{
	58	shmid64->shm_perm = kshmid->shm_perm;
	59	shmid64->shm_segsz = kshmid->shm_segsz;
	60	shmid64->shm_atime = kshmid->shm_atime
	61	\| ((__time64_t) kshmid->shm_atime_high << 32);
	62	shmid64->shm_dtime = kshmid->shm_dtime
	63	\| ((__time64_t) kshmid->shm_dtime_high << 32);
	64	shmid64->shm_ctime = kshmid->shm_ctime
	65	\| ((__time64_t) kshmid->shm_ctime_high << 32);
	66	shmid64->shm_cpid = kshmid->shm_cpid;
	67	shmid64->shm_lpid = kshmid->shm_lpid;
	68	shmid64->shm_nattch = kshmid->shm_nattch;
	69	}
	70
	71	typedef struct kernel_shmid64_ds shmctl_arg_t;
e01f79e4	72	#endif
0482576e	73
2f959dfe	74	static int
ffd178c6	75	shmctl_syscall (int shmid, int cmd, shmctl_arg_t *buf)
e01f79e4 AZ	76	{
	77	#ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
	78	return INLINE_SYSCALL_CALL (shmctl, shmid, cmd \| __IPC_64, buf);
	79	#else
	80	return INLINE_SYSCALL_CALL (ipc, IPCOP_shmctl, shmid, cmd \| __IPC_64, 0,
	81	buf);
	82	#endif
	83	}
2f959dfe AZ	84
	85	/* Provide operations to control over shared memory segments. */
	86	int
ffd178c6	87	__shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
2f959dfe	88	{
ffd178c6 AZ	89	#if __IPC_TIME64
ffd178c6 AZ	90	struct kernel_shmid64_ds kshmid, *arg = NULL;
9ebaabea AZ	91	#else
	92	shmctl_arg_t *arg;
	93	#endif
	94
	95	switch (cmd)
2f959dfe	96	{
9ebaabea AZ	97	case IPC_RMID:
	98	case SHM_LOCK:
	99	case SHM_UNLOCK:
	100	arg = NULL;
	101	break;
	102
	103	case IPC_SET:
	104	case IPC_STAT:
	105	case SHM_STAT:
	106	case SHM_STAT_ANY:
	107	#if __IPC_TIME64
	108	if (buf != NULL)
a49d7fd4 AZ	109	{
	110	shmid64_to_kshmid64 (buf, &kshmid);
	111	arg = &kshmid;
	112	}
ffd178c6	113	# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
9ebaabea AZ	114	if (cmd == IPC_SET)
9ebaabea AZ	115	arg->shm_perm.mode *= 0x10000U;
ffd178c6 AZ	116	# endif
ffd178c6 AZ	117	#else
9ebaabea	118	arg = buf;
2f959dfe	119	#endif
9ebaabea AZ	120	break;
	121
	122	case IPC_INFO:
	123	case SHM_INFO:
	124	/* This is a Linux extension where kernel expects either a
	125	'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
	126	arg = (__typeof__ (arg)) buf;
	127	break;
	128
	129	default:
	130	__set_errno (EINVAL);
	131	return -1;
	132	}
	133
2f959dfe	134
ffd178c6 AZ	135	int ret = shmctl_syscall (shmid, cmd, arg);
	136	if (ret < 0)
	137	return ret;
2f959dfe	138
ffd178c6	139	switch (cmd)
2f959dfe	140	{
ffd178c6 AZ	141	case IPC_STAT:
	142	case SHM_STAT:
	143	case SHM_STAT_ANY:
24fdebe7	144	#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
ffd178c6	145	arg->shm_perm.mode >>= 16;
24fdebe7	146	#else
ffd178c6 AZ	147	/* Old Linux kernel versions might not clear the mode padding. */
	148	if (sizeof ((struct shmid_ds){0}.shm_perm.mode)
	149	!= sizeof (__kernel_mode_t))
	150	arg->shm_perm.mode &= 0xFFFF;
	151	#endif
	152
	153	#if __IPC_TIME64
	154	kshmid64_to_shmid64 (arg, buf);
24fdebe7	155	#endif
2f959dfe	156	}
2f959dfe AZ	157
	158	return ret;
	159	}
ffd178c6 AZ	160	#if __TIMESIZE != 64
	161	libc_hidden_def (__shmctl64)
	162
	163	static void
	164	shmid_to_shmid64 (struct __shmid64_ds shm64, const struct shmid_ds shm)
	165	{
	166	shm64->shm_perm = shm->shm_perm;
	167	shm64->shm_segsz = shm->shm_segsz;
	168	shm64->shm_atime = shm->shm_atime
	169	\| ((__time64_t) shm->__shm_atime_high << 32);
	170	shm64->shm_dtime = shm->shm_dtime
	171	\| ((__time64_t) shm->__shm_dtime_high << 32);
	172	shm64->shm_ctime = shm->shm_ctime
	173	\| ((__time64_t) shm->__shm_ctime_high << 32);
	174	shm64->shm_cpid = shm->shm_cpid;
	175	shm64->shm_lpid = shm->shm_lpid;
	176	shm64->shm_nattch = shm->shm_nattch;
	177	}
	178
	179	static void
	180	shmid64_to_shmid (struct shmid_ds shm, const struct __shmid64_ds shm64)
	181	{
	182	shm->shm_perm = shm64->shm_perm;
	183	shm->shm_segsz = shm64->shm_segsz;
	184	shm->shm_atime = shm64->shm_atime;
	185	shm->__shm_atime_high = 0;
	186	shm->shm_dtime = shm64->shm_dtime;
	187	shm->__shm_dtime_high = 0;
	188	shm->shm_ctime = shm64->shm_ctime;
	189	shm->__shm_ctime_high = 0;
	190	shm->shm_cpid = shm64->shm_cpid;
	191	shm->shm_lpid = shm64->shm_lpid;
	192	shm->shm_nattch = shm64->shm_nattch;
	193	}
	194
	195	int
	196	__shmctl (int shmid, int cmd, struct shmid_ds *buf)
	197	{
	198	struct __shmid64_ds shmid64, *buf64 = NULL;
	199	if (buf != NULL)
	200	{
a49d7fd4 AZ	201	/* This is a Linux extension where kernel expects either a
	202	'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
	203	if (cmd == IPC_INFO \|\| cmd == SHM_INFO)
	204	buf64 = (struct __shmid64_ds *) buf;
	205	else
	206	{
	207	shmid_to_shmid64 (&shmid64, buf);
	208	buf64 = &shmid64;
	209	}
ffd178c6 AZ	210	}
	211
	212	int ret = __shmctl64 (shmid, cmd, buf64);
	213	if (ret < 0)
	214	return ret;
	215
	216	switch (cmd)
	217	{
ffd178c6 AZ	218	case IPC_STAT:
	219	case SHM_STAT:
	220	case SHM_STAT_ANY:
	221	shmid64_to_shmid (buf, buf64);
	222	}
	223
	224	return ret;
	225	}
	226	#endif
	227
	228	#ifndef DEFAULT_VERSION
	229	# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T
	230	# define DEFAULT_VERSION GLIBC_2_2
	231	# else
	232	# define DEFAULT_VERSION GLIBC_2_31
	233	# endif
	234	#endif
	235
	236	versioned_symbol (libc, __shmctl, shmctl, DEFAULT_VERSION);
e01f79e4	237
2f959dfe AZ	238	#if defined __ASSUME_SYSVIPC_BROKEN_MODE_T \
	239	&& SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_31)
	240	int
	241	attribute_compat_text_section
	242	__shmctl_mode16 (int shmid, int cmd, struct shmid_ds *buf)
	243	{
ffd178c6	244	return shmctl_syscall (shmid, cmd, (shmctl_arg_t *) buf);
2f959dfe AZ	245	}
	246	compat_symbol (libc, __shmctl_mode16, shmctl, GLIBC_2_2);
	247	#endif
e01f79e4 AZ	248
e01f79e4 AZ	249	#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)
973209d8 UD	250	struct __old_shmid_ds
	251	{
	252	struct __old_ipc_perm shm_perm; /* operation permission struct */
	253	int shm_segsz; /* size of segment in bytes */
	254	__time_t shm_atime; /* time of last shmat() */
	255	__time_t shm_dtime; /* time of last shmdt() */
	256	__time_t shm_ctime; /* time of last change by shmctl() */
	257	__ipc_pid_t shm_cpid; /* pid of creator */
	258	__ipc_pid_t shm_lpid; /* pid of last shmop */
	259	unsigned short int shm_nattch; /* number of current attaches */
	260	unsigned short int __shm_npages; /* size of segment (pages) */
70d9946a JM	261	unsigned long int __shm_pages; / array of ptrs to frames -> SHMMAX */
70d9946a JM	262	struct vm_area_struct __attaches; / descriptors for attaches */
973209d8 UD	263	};
973209d8 UD	264
d2f5be2a	265	int
d3a4a571	266	attribute_compat_text_section
0482576e	267	__old_shmctl (int shmid, int cmd, struct __old_shmid_ds *buf)
d2f5be2a	268	{
720e9541 AZ	269	#if defined __ASSUME_DIRECT_SYSVIPC_SYSCALLS \
	270	&& !defined __ASSUME_SYSVIPC_DEFAULT_IPC_64
	271	/* For architecture that have wire-up shmctl but also have __IPC_64 to a
	272	value different than default (0x0), it means the compat symbol used the
	273	__NR_ipc syscall. */
e01f79e4 AZ	274	return INLINE_SYSCALL_CALL (shmctl, shmid, cmd, buf);
	275	#else
	276	return INLINE_SYSCALL_CALL (ipc, IPCOP_shmctl, shmid, cmd, 0, buf);
	277	#endif
d2f5be2a	278	}
b5567b2a UD	279	compat_symbol (libc, __old_shmctl, shmctl, GLIBC_2_0);
b5567b2a UD	280	#endif