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Fix a copy/paste bug introduced during X86_64 Linuxulator work.

Browse Source 
FreeBSD support NX bit on X86_64 processors out of the box, for i386 emulation
use READ_IMPLIES_EXEC flag, introduced in r302515.

While here move common part of mmap() and mprotect() code to the files in compat/linux
to reduce code dupcliation between Linuxulator's.

Reported by:    Johannes Jost Meixner, Shawn Webb

MFC after:	1 week
XMFC with:	r302515, r302516
This commit is contained in:
Dmitry Chagin 2016-07-10 08:22:04 +00:00
parent ab231b83ea
commit 97d06da692
10 changed files with 316 additions and 552 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
sys/amd64/linux/linux.h
View File

@ -139,13 +139,6 @@ struct l_rlimit {
l_ulong rlim_max;
};
/* mmap options */
#define LINUX_MAP_SHARED 0x0001
#define LINUX_MAP_PRIVATE 0x0002
#define LINUX_MAP_FIXED 0x0010
#define LINUX_MAP_ANON 0x0020
#define LINUX_MAP_GROWSDOWN 0x0100
/*
* stat family of syscalls
*/

169
sys/amd64/linux/linux_machdep.c
View File

@ -83,6 +83,7 @@ __FBSDID("$FreeBSD$");
#include <compat/linux/linux_ipc.h>
#include <compat/linux/linux_file.h>
#include <compat/linux/linux_misc.h>
#include <compat/linux/linux_mmap.h>
#include <compat/linux/linux_signal.h>
#include <compat/linux/linux_util.h>
#include <compat/linux/linux_emul.h>
@ -122,181 +123,19 @@ linux_set_upcall_kse(struct thread *td, register_t stack)
return (0);
}
#define STACK_SIZE (2 * 1024 * 1024)
#define GUARD_SIZE (4 * PAGE_SIZE)
int
linux_mmap2(struct thread *td, struct linux_mmap2_args *args)
{
struct proc *p = td->td_proc;
struct mmap_args /* {
caddr_t addr;
size_t len;
int prot;
int flags;
int fd;
long pad;
off_t pos;
} */ bsd_args;
int error;
struct file *fp;
cap_rights_t rights;
LINUX_CTR6(mmap2, "0x%lx, %ld, %ld, 0x%08lx, %ld, 0x%lx",
args->addr, args->len, args->prot,
args->flags, args->fd, args->pgoff);
error = 0;
bsd_args.flags = 0;
fp = NULL;
/*
* Linux mmap(2):
* You must specify exactly one of MAP_SHARED and MAP_PRIVATE
*/
if (! ((args->flags & LINUX_MAP_SHARED) ^
(args->flags & LINUX_MAP_PRIVATE)))
return (EINVAL);
if (args->flags & LINUX_MAP_SHARED)
bsd_args.flags |= MAP_SHARED;
if (args->flags & LINUX_MAP_PRIVATE)
bsd_args.flags |= MAP_PRIVATE;
if (args->flags & LINUX_MAP_FIXED)
bsd_args.flags |= MAP_FIXED;
if (args->flags & LINUX_MAP_ANON)
bsd_args.flags |= MAP_ANON;
else
bsd_args.flags |= MAP_NOSYNC;
if (args->flags & LINUX_MAP_GROWSDOWN)
bsd_args.flags |= MAP_STACK;
/*
* PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC
* on Linux/i386. We do this to ensure maximum compatibility.
* Linux/ia64 does the same in i386 emulation mode.
*/
bsd_args.prot = args->prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
/* Linux does not check file descriptor when MAP_ANONYMOUS is set. */
bsd_args.fd = (bsd_args.flags & MAP_ANON) ? -1 : args->fd;
if (bsd_args.fd != -1) {
/*
* Linux follows Solaris mmap(2) description:
* The file descriptor fildes is opened with
* read permission, regardless of the
* protection options specified.
*/
error = fget(td, bsd_args.fd,
cap_rights_init(&rights, CAP_MMAP), &fp);
if (error != 0 )
return (error);
if (fp->f_type != DTYPE_VNODE) {
fdrop(fp, td);
return (EINVAL);
}
/* Linux mmap() just fails for O_WRONLY files */
if (!(fp->f_flag & FREAD)) {
fdrop(fp, td);
return (EACCES);
}
fdrop(fp, td);
}
if (args->flags & LINUX_MAP_GROWSDOWN) {
/*
* The Linux MAP_GROWSDOWN option does not limit auto
* growth of the region. Linux mmap with this option
* takes as addr the initial BOS, and as len, the initial
* region size. It can then grow down from addr without
* limit. However, Linux threads has an implicit internal
* limit to stack size of STACK_SIZE. Its just not
* enforced explicitly in Linux. But, here we impose
* a limit of (STACK_SIZE - GUARD_SIZE) on the stack
* region, since we can do this with our mmap.
*
* Our mmap with MAP_STACK takes addr as the maximum
* downsize limit on BOS, and as len the max size of
* the region. It then maps the top SGROWSIZ bytes,
* and auto grows the region down, up to the limit
* in addr.
*
* If we don't use the MAP_STACK option, the effect
* of this code is to allocate a stack region of a
* fixed size of (STACK_SIZE - GUARD_SIZE).
*/
if ((caddr_t)PTRIN(args->addr) + args->len >
p->p_vmspace->vm_maxsaddr) {
/*
* Some Linux apps will attempt to mmap
* thread stacks near the top of their
* address space. If their TOS is greater
* than vm_maxsaddr, vm_map_growstack()
* will confuse the thread stack with the
* process stack and deliver a SEGV if they
* attempt to grow the thread stack past their
* current stacksize rlimit. To avoid this,
* adjust vm_maxsaddr upwards to reflect
* the current stacksize rlimit rather
* than the maximum possible stacksize.
* It would be better to adjust the
* mmap'ed region, but some apps do not check
* mmap's return value.
*/
PROC_LOCK(p);
p->p_vmspace->vm_maxsaddr = (char *)USRSTACK -
lim_cur_proc(p, RLIMIT_STACK);
PROC_UNLOCK(p);
}
/*
* This gives us our maximum stack size and a new BOS.
* If we're using VM_STACK, then mmap will just map
* the top SGROWSIZ bytes, and let the stack grow down
* to the limit at BOS. If we're not using VM_STACK
* we map the full stack, since we don't have a way
* to autogrow it.
*/
if (args->len > STACK_SIZE - GUARD_SIZE) {
bsd_args.addr = (caddr_t)PTRIN(args->addr);
bsd_args.len = args->len;
} else {
bsd_args.addr = (caddr_t)PTRIN(args->addr) -
(STACK_SIZE - GUARD_SIZE - args->len);
bsd_args.len = STACK_SIZE - GUARD_SIZE;
}
} else {
bsd_args.addr = (caddr_t)PTRIN(args->addr);
bsd_args.len = args->len;
}
bsd_args.pos = (off_t)args->pgoff;
error = sys_mmap(td, &bsd_args);
LINUX_CTR2(mmap2, "return: %d (%p)",
error, td->td_retval[0]);
return (error);
return (linux_mmap_common(td, PTROUT(args->addr), args->len, args->prot,
args->flags, args->fd, args->pgoff));
}
int
linux_mprotect(struct thread *td, struct linux_mprotect_args *uap)
{
struct mprotect_args bsd_args;
LINUX_CTR(mprotect);
bsd_args.addr = uap->addr;
bsd_args.len = uap->len;
bsd_args.prot = uap->prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
return (sys_mprotect(td, &bsd_args));
return (linux_mprotect_common(td, PTROUT(uap->addr), uap->len, uap->prot));
}
int

7
sys/amd64/linux32/linux.h
View File

@ -165,13 +165,6 @@ struct l_rusage {
l_long ru_nivcsw;
} __packed;
/* mmap options */
#define LINUX_MAP_SHARED 0x0001
#define LINUX_MAP_PRIVATE 0x0002
#define LINUX_MAP_FIXED 0x0010
#define LINUX_MAP_ANON 0x0020
#define LINUX_MAP_GROWSDOWN 0x0100
struct l_mmap_argv {
l_uintptr_t addr;
l_size_t len;

182
sys/amd64/linux32/linux32_machdep.c
View File

@ -70,6 +70,7 @@ __FBSDID("$FreeBSD$");
#include <amd64/linux32/linux32_proto.h>
#include <compat/linux/linux_ipc.h>
#include <compat/linux/linux_misc.h>
#include <compat/linux/linux_mmap.h>
#include <compat/linux/linux_signal.h>
#include <compat/linux/linux_util.h>
#include <compat/linux/linux_emul.h>
@ -84,9 +85,6 @@ struct l_old_select_argv {
l_uintptr_t timeout;
} __packed;
static int linux_mmap_common(struct thread *td, l_uintptr_t addr,
l_size_t len, l_int prot, l_int flags, l_int fd,
l_loff_t pos);
static void
bsd_to_linux_rusage(struct rusage *ru, struct l_rusage *lru)
@ -448,9 +446,6 @@ linux_set_upcall_kse(struct thread *td, register_t stack)
return (0);
}
#define STACK_SIZE (2 * 1024 * 1024)
#define GUARD_SIZE (4 * PAGE_SIZE)
int
linux_mmap2(struct thread *td, struct linux_mmap2_args *args)
{
@ -489,184 +484,11 @@ linux_mmap(struct thread *td, struct linux_mmap_args *args)
(uint32_t)linux_args.pgoff));
}
static int
linux_mmap_common(struct thread *td, l_uintptr_t addr, l_size_t len, l_int prot,
l_int flags, l_int fd, l_loff_t pos)
{
struct proc *p = td->td_proc;
struct mmap_args /* {
caddr_t addr;
size_t len;
int prot;
int flags;
int fd;
long pad;
off_t pos;
} */ bsd_args;
int error;
struct file *fp;
cap_rights_t rights;
error = 0;
bsd_args.flags = 0;
fp = NULL;
/*
* Linux mmap(2):
* You must specify exactly one of MAP_SHARED and MAP_PRIVATE
*/
if (!((flags & LINUX_MAP_SHARED) ^ (flags & LINUX_MAP_PRIVATE)))
return (EINVAL);
if (flags & LINUX_MAP_SHARED)
bsd_args.flags |= MAP_SHARED;
if (flags & LINUX_MAP_PRIVATE)
bsd_args.flags |= MAP_PRIVATE;
if (flags & LINUX_MAP_FIXED)
bsd_args.flags |= MAP_FIXED;
if (flags & LINUX_MAP_ANON) {
/* Enforce pos to be on page boundary, then ignore. */
if ((pos & PAGE_MASK) != 0)
return (EINVAL);
pos = 0;
bsd_args.flags |= MAP_ANON;
} else
bsd_args.flags |= MAP_NOSYNC;
if (flags & LINUX_MAP_GROWSDOWN)
bsd_args.flags |= MAP_STACK;
/*
* PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC
* on Linux/i386. We do this to ensure maximum compatibility.
* Linux/ia64 does the same in i386 emulation mode.
*/
bsd_args.prot = prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
/* Linux does not check file descriptor when MAP_ANONYMOUS is set. */
bsd_args.fd = (bsd_args.flags & MAP_ANON) ? -1 : fd;
if (bsd_args.fd != -1) {
/*
* Linux follows Solaris mmap(2) description:
* The file descriptor fildes is opened with
* read permission, regardless of the
* protection options specified.
*/
error = fget(td, bsd_args.fd,
cap_rights_init(&rights, CAP_MMAP), &fp);
if (error != 0)
return (error);
if (fp->f_type != DTYPE_VNODE) {
fdrop(fp, td);
return (EINVAL);
}
/* Linux mmap() just fails for O_WRONLY files */
if (!(fp->f_flag & FREAD)) {
fdrop(fp, td);
return (EACCES);
}
fdrop(fp, td);
}
if (flags & LINUX_MAP_GROWSDOWN) {
/*
* The Linux MAP_GROWSDOWN option does not limit auto
* growth of the region. Linux mmap with this option
* takes as addr the initial BOS, and as len, the initial
* region size. It can then grow down from addr without
* limit. However, Linux threads has an implicit internal
* limit to stack size of STACK_SIZE. Its just not
* enforced explicitly in Linux. But, here we impose
* a limit of (STACK_SIZE - GUARD_SIZE) on the stack
* region, since we can do this with our mmap.
*
* Our mmap with MAP_STACK takes addr as the maximum
* downsize limit on BOS, and as len the max size of
* the region. It then maps the top SGROWSIZ bytes,
* and auto grows the region down, up to the limit
* in addr.
*
* If we don't use the MAP_STACK option, the effect
* of this code is to allocate a stack region of a
* fixed size of (STACK_SIZE - GUARD_SIZE).
*/
if ((caddr_t)PTRIN(addr) + len > p->p_vmspace->vm_maxsaddr) {
/*
* Some Linux apps will attempt to mmap
* thread stacks near the top of their
* address space. If their TOS is greater
* than vm_maxsaddr, vm_map_growstack()
* will confuse the thread stack with the
* process stack and deliver a SEGV if they
* attempt to grow the thread stack past their
* current stacksize rlimit. To avoid this,
* adjust vm_maxsaddr upwards to reflect
* the current stacksize rlimit rather
* than the maximum possible stacksize.
* It would be better to adjust the
* mmap'ed region, but some apps do not check
* mmap's return value.
*/
PROC_LOCK(p);
p->p_vmspace->vm_maxsaddr = (char *)LINUX32_USRSTACK -
lim_cur_proc(p, RLIMIT_STACK);
PROC_UNLOCK(p);
}
/*
* This gives us our maximum stack size and a new BOS.
* If we're using VM_STACK, then mmap will just map
* the top SGROWSIZ bytes, and let the stack grow down
* to the limit at BOS. If we're not using VM_STACK
* we map the full stack, since we don't have a way
* to autogrow it.
*/
if (len > STACK_SIZE - GUARD_SIZE) {
bsd_args.addr = (caddr_t)PTRIN(addr);
bsd_args.len = len;
} else {
bsd_args.addr = (caddr_t)PTRIN(addr) -
(STACK_SIZE - GUARD_SIZE - len);
bsd_args.len = STACK_SIZE - GUARD_SIZE;
}
} else {
bsd_args.addr = (caddr_t)PTRIN(addr);
bsd_args.len = len;
}
bsd_args.pos = pos;
#ifdef DEBUG
if (ldebug(mmap))
printf("-> %s(%p, %d, %d, 0x%08x, %d, 0x%x)\n",
__func__,
(void *)bsd_args.addr, (int)bsd_args.len, bsd_args.prot,
bsd_args.flags, bsd_args.fd, (int)bsd_args.pos);
#endif
error = sys_mmap(td, &bsd_args);
#ifdef DEBUG
if (ldebug(mmap))
printf("-> %s() return: 0x%x (0x%08x)\n",
__func__, error, (u_int)td->td_retval[0]);
#endif
return (error);
}
int
linux_mprotect(struct thread *td, struct linux_mprotect_args *uap)
{
struct mprotect_args bsd_args;
bsd_args.addr = uap->addr;
bsd_args.len = uap->len;
bsd_args.prot = uap->prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
return (sys_mprotect(td, &bsd_args));
return (linux_mprotect_common(td, PTROUT(uap->addr), uap->len, uap->prot));
}
int

257
sys/compat/linux/linux_mmap.c Normal file
View File

@ -0,0 +1,257 @@
/*-
* Copyright (c) 2004 Tim J. Robbins
* Copyright (c) 2002 Doug Rabson
* Copyright (c) 2000 Marcel Moolenaar
* Copyright (c) 1994-1995 Søren Schmidt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/capsicum.h>
#include <sys/file.h>
#include <sys/imgact.h>
#include <sys/ktr.h>
#include <sys/mman.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sysent.h>
#include <sys/sysproto.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <compat/linux/linux_emul.h>
#include <compat/linux/linux_mmap.h>
#include <compat/linux/linux_persona.h>
#include <compat/linux/linux_util.h>
#define STACK_SIZE (2 * 1024 * 1024)
#define GUARD_SIZE (4 * PAGE_SIZE)
#if defined(__amd64__)
static void linux_fixup_prot(struct thread *td, int *prot);
#endif
int
linux_mmap_common(struct thread *td, uintptr_t addr, size_t len, int prot,
int flags, int fd, off_t pos)
{
struct proc *p = td->td_proc;
struct vmspace *vms = td->td_proc->p_vmspace;
struct mmap_args /* {
caddr_t addr;
size_t len;
int prot;
int flags;
int fd;
off_t pos;
} */ bsd_args;
int error;
struct file *fp;
cap_rights_t rights;
LINUX_CTR6(mmap2, "0x%lx, %ld, %ld, 0x%08lx, %ld, 0x%lx",
addr, len, prot, flags, fd, pos);
error = 0;
bsd_args.flags = 0;
fp = NULL;
/*
* Linux mmap(2):
* You must specify exactly one of MAP_SHARED and MAP_PRIVATE
*/
if (!((flags & LINUX_MAP_SHARED) ^ (flags & LINUX_MAP_PRIVATE)))
return (EINVAL);
if (flags & LINUX_MAP_SHARED)
bsd_args.flags |= MAP_SHARED;
if (flags & LINUX_MAP_PRIVATE)
bsd_args.flags |= MAP_PRIVATE;
if (flags & LINUX_MAP_FIXED)
bsd_args.flags |= MAP_FIXED;
if (flags & LINUX_MAP_ANON) {
/* Enforce pos to be on page boundary, then ignore. */
if ((pos & PAGE_MASK) != 0)
return (EINVAL);
pos = 0;
bsd_args.flags |= MAP_ANON;
} else
bsd_args.flags |= MAP_NOSYNC;
if (flags & LINUX_MAP_GROWSDOWN)
bsd_args.flags |= MAP_STACK;
/*
* PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC
* on Linux/i386 if the binary requires executable stack.
* We do this only for IA32 emulation as on native i386 this is does not
* make sense without PAE.
*
* XXX. Linux checks that the file system is not mounted with noexec.
*/
bsd_args.prot = prot;
#if defined(__amd64__)
linux_fixup_prot(td, &bsd_args.prot);
#endif
/* Linux does not check file descriptor when MAP_ANONYMOUS is set. */
bsd_args.fd = (bsd_args.flags & MAP_ANON) ? -1 : fd;
if (bsd_args.fd != -1) {
/*
* Linux follows Solaris mmap(2) description:
* The file descriptor fildes is opened with
* read permission, regardless of the
* protection options specified.
*/
error = fget(td, bsd_args.fd,
cap_rights_init(&rights, CAP_MMAP), &fp);
if (error != 0)
return (error);
if (fp->f_type != DTYPE_VNODE) {
fdrop(fp, td);
return (EINVAL);
}
/* Linux mmap() just fails for O_WRONLY files */
if (!(fp->f_flag & FREAD)) {
fdrop(fp, td);
return (EACCES);
}
fdrop(fp, td);
}
if (flags & LINUX_MAP_GROWSDOWN) {
/*
* The Linux MAP_GROWSDOWN option does not limit auto
* growth of the region. Linux mmap with this option
* takes as addr the initial BOS, and as len, the initial
* region size. It can then grow down from addr without
* limit. However, Linux threads has an implicit internal
* limit to stack size of STACK_SIZE. Its just not
* enforced explicitly in Linux. But, here we impose
* a limit of (STACK_SIZE - GUARD_SIZE) on the stack
* region, since we can do this with our mmap.
*
* Our mmap with MAP_STACK takes addr as the maximum
* downsize limit on BOS, and as len the max size of
* the region. It then maps the top SGROWSIZ bytes,
* and auto grows the region down, up to the limit
* in addr.
*
* If we don't use the MAP_STACK option, the effect
* of this code is to allocate a stack region of a
* fixed size of (STACK_SIZE - GUARD_SIZE).
*/
if ((caddr_t)addr + len > vms->vm_maxsaddr) {
/*
* Some Linux apps will attempt to mmap
* thread stacks near the top of their
* address space. If their TOS is greater
* than vm_maxsaddr, vm_map_growstack()
* will confuse the thread stack with the
* process stack and deliver a SEGV if they
* attempt to grow the thread stack past their
* current stacksize rlimit. To avoid this,
* adjust vm_maxsaddr upwards to reflect
* the current stacksize rlimit rather
* than the maximum possible stacksize.
* It would be better to adjust the
* mmap'ed region, but some apps do not check
* mmap's return value.
*/
PROC_LOCK(p);
vms->vm_maxsaddr = (char *)p->p_sysent->sv_usrstack -
lim_cur_proc(p, RLIMIT_STACK);
PROC_UNLOCK(p);
}
/*
* This gives us our maximum stack size and a new BOS.
* If we're using VM_STACK, then mmap will just map
* the top SGROWSIZ bytes, and let the stack grow down
* to the limit at BOS. If we're not using VM_STACK
* we map the full stack, since we don't have a way
* to autogrow it.
*/
if (len > STACK_SIZE - GUARD_SIZE) {
bsd_args.addr = (caddr_t)addr;
bsd_args.len = len;
} else {
bsd_args.addr = (caddr_t)addr -
(STACK_SIZE - GUARD_SIZE - len);
bsd_args.len = STACK_SIZE - GUARD_SIZE;
}
} else {
bsd_args.addr = (caddr_t)addr;
bsd_args.len = len;
}
bsd_args.pos = pos;
error = sys_mmap(td, &bsd_args);
LINUX_CTR2(mmap2, "return: %d (%p)", error, td->td_retval[0]);
return (error);
}
int
linux_mprotect_common(struct thread *td, uintptr_t addr, size_t len, int prot)
{
struct mprotect_args bsd_args;
bsd_args.addr = (void *)addr;
bsd_args.len = len;
bsd_args.prot = prot;
#if defined(__amd64__)
linux_fixup_prot(td, &bsd_args.prot);
#endif
return (sys_mprotect(td, &bsd_args));
}
#if defined(__amd64__)
static void
linux_fixup_prot(struct thread *td, int *prot)
{
struct linux_pemuldata *pem;
if (SV_PROC_FLAG(td->td_proc, SV_ILP32) && *prot & PROT_READ) {
pem = pem_find(td->td_proc);
if (pem->persona & LINUX_READ_IMPLIES_EXEC)
*prot |= PROT_EXEC;
}
}
#endif

49
sys/compat/linux/linux_mmap.h Normal file
View File

@ -0,0 +1,49 @@
/*-
* Copyright (c) 2004 Tim J. Robbins
* Copyright (c) 2002 Doug Rabson
* Copyright (c) 2000 Marcel Moolenaar
* Copyright (c) 1994-1995 Søren Schmidt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _LINUX_MMAP_H_
#define _LINUX_MMAP_H_
/* mmap options */
#define LINUX_MAP_SHARED 0x0001
#define LINUX_MAP_PRIVATE 0x0002
#define LINUX_MAP_FIXED 0x0010
#define LINUX_MAP_ANON 0x0020
#define LINUX_MAP_GROWSDOWN 0x0100
int linux_mmap_common(struct thread *, uintptr_t, size_t, int, int,
int, off_t);
int linux_mprotect_common(struct thread *, uintptr_t, size_t, int);
#endif /* _LINUX_MMAP_H_ */

7
sys/i386/linux/linux.h
View File

@ -140,13 +140,6 @@ struct l_rlimit {
l_ulong rlim_max;
};
/* mmap options */
#define LINUX_MAP_SHARED 0x0001
#define LINUX_MAP_PRIVATE 0x0002
#define LINUX_MAP_FIXED 0x0010
#define LINUX_MAP_ANON 0x0020
#define LINUX_MAP_GROWSDOWN 0x0100
struct l_mmap_argv {
l_uintptr_t addr;
l_size_t len;

186
sys/i386/linux/linux_machdep.c
View File

@ -65,6 +65,7 @@ __FBSDID("$FreeBSD$");
#include <i386/linux/linux_proto.h>
#include <compat/linux/linux_ipc.h>
#include <compat/linux/linux_misc.h>
#include <compat/linux/linux_mmap.h>
#include <compat/linux/linux_signal.h>
#include <compat/linux/linux_util.h>
#include <compat/linux/linux_emul.h>
@ -95,10 +96,6 @@ struct l_old_select_argv {
struct l_timeval *timeout;
};
static int linux_mmap_common(struct thread *td, l_uintptr_t addr,
l_size_t len, l_int prot, l_int flags, l_int fd,
l_loff_t pos);
int
linux_execve(struct thread *td, struct linux_execve_args *args)
@ -340,9 +337,6 @@ linux_set_upcall_kse(struct thread *td, register_t stack)
return (0);
}
#define STACK_SIZE (2 * 1024 * 1024)
#define GUARD_SIZE (4 * PAGE_SIZE)
int
linux_mmap2(struct thread *td, struct linux_mmap2_args *args)
{
@ -381,187 +375,11 @@ linux_mmap(struct thread *td, struct linux_mmap_args *args)
(uint32_t)linux_args.pgoff));
}
static int
linux_mmap_common(struct thread *td, l_uintptr_t addr, l_size_t len, l_int prot,
l_int flags, l_int fd, l_loff_t pos)
{
struct proc *p = td->td_proc;
struct mmap_args /* {
caddr_t addr;
size_t len;
int prot;
int flags;
int fd;
long pad;
off_t pos;
} */ bsd_args;
int error;
struct file *fp;
cap_rights_t rights;
error = 0;
bsd_args.flags = 0;
fp = NULL;
/*
* Linux mmap(2):
* You must specify exactly one of MAP_SHARED and MAP_PRIVATE
*/
if (!((flags & LINUX_MAP_SHARED) ^ (flags & LINUX_MAP_PRIVATE)))
return (EINVAL);
if (flags & LINUX_MAP_SHARED)
bsd_args.flags |= MAP_SHARED;
if (flags & LINUX_MAP_PRIVATE)
bsd_args.flags |= MAP_PRIVATE;
if (flags & LINUX_MAP_FIXED)
bsd_args.flags |= MAP_FIXED;
if (flags & LINUX_MAP_ANON) {
/* Enforce pos to be on page boundary, then ignore. */
if ((pos & PAGE_MASK) != 0)
return (EINVAL);
pos = 0;
bsd_args.flags |= MAP_ANON;
} else
bsd_args.flags |= MAP_NOSYNC;
if (flags & LINUX_MAP_GROWSDOWN)
bsd_args.flags |= MAP_STACK;
/*
* PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC
* on Linux/i386. We do this to ensure maximum compatibility.
* Linux/ia64 does the same in i386 emulation mode.
*/
bsd_args.prot = prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
/* Linux does not check file descriptor when MAP_ANONYMOUS is set. */
bsd_args.fd = (bsd_args.flags & MAP_ANON) ? -1 : fd;
if (bsd_args.fd != -1) {
/*
* Linux follows Solaris mmap(2) description:
* The file descriptor fildes is opened with
* read permission, regardless of the
* protection options specified.
*
* Checking just CAP_MMAP is fine here, since the real work
* is done in the FreeBSD mmap().
*/
error = fget(td, bsd_args.fd,
cap_rights_init(&rights, CAP_MMAP), &fp);
if (error != 0)
return (error);
if (fp->f_type != DTYPE_VNODE) {
fdrop(fp, td);
return (EINVAL);
}
/* Linux mmap() just fails for O_WRONLY files */
if (!(fp->f_flag & FREAD)) {
fdrop(fp, td);
return (EACCES);
}
fdrop(fp, td);
}
if (flags & LINUX_MAP_GROWSDOWN) {
/*
* The Linux MAP_GROWSDOWN option does not limit auto
* growth of the region. Linux mmap with this option
* takes as addr the inital BOS, and as len, the initial
* region size. It can then grow down from addr without
* limit. However, linux threads has an implicit internal
* limit to stack size of STACK_SIZE. Its just not
* enforced explicitly in linux. But, here we impose
* a limit of (STACK_SIZE - GUARD_SIZE) on the stack
* region, since we can do this with our mmap.
*
* Our mmap with MAP_STACK takes addr as the maximum
* downsize limit on BOS, and as len the max size of
* the region. It them maps the top SGROWSIZ bytes,
* and auto grows the region down, up to the limit
* in addr.
*
* If we don't use the MAP_STACK option, the effect
* of this code is to allocate a stack region of a
* fixed size of (STACK_SIZE - GUARD_SIZE).
*/
if ((caddr_t)PTRIN(addr) + len > p->p_vmspace->vm_maxsaddr) {
/*
* Some linux apps will attempt to mmap
* thread stacks near the top of their
* address space. If their TOS is greater
* than vm_maxsaddr, vm_map_growstack()
* will confuse the thread stack with the
* process stack and deliver a SEGV if they
* attempt to grow the thread stack past their
* current stacksize rlimit. To avoid this,
* adjust vm_maxsaddr upwards to reflect
* the current stacksize rlimit rather
* than the maximum possible stacksize.
* It would be better to adjust the
* mmap'ed region, but some apps do not check
* mmap's return value.
*/
PROC_LOCK(p);
p->p_vmspace->vm_maxsaddr = (char *)USRSTACK -
lim_cur_proc(p, RLIMIT_STACK);
PROC_UNLOCK(p);
}
/*
* This gives us our maximum stack size and a new BOS.
* If we're using VM_STACK, then mmap will just map
* the top SGROWSIZ bytes, and let the stack grow down
* to the limit at BOS. If we're not using VM_STACK
* we map the full stack, since we don't have a way
* to autogrow it.
*/
if (len > STACK_SIZE - GUARD_SIZE) {
bsd_args.addr = (caddr_t)PTRIN(addr);
bsd_args.len = len;
} else {
bsd_args.addr = (caddr_t)PTRIN(addr) -
(STACK_SIZE - GUARD_SIZE - len);
bsd_args.len = STACK_SIZE - GUARD_SIZE;
}
} else {
bsd_args.addr = (caddr_t)PTRIN(addr);
bsd_args.len = len;
}
bsd_args.pos = pos;
#ifdef DEBUG
if (ldebug(mmap))
printf("-> %s(%p, %d, %d, 0x%08x, %d, 0x%x)\n",
__func__,
(void *)bsd_args.addr, bsd_args.len, bsd_args.prot,
bsd_args.flags, bsd_args.fd, (int)bsd_args.pos);
#endif
error = sys_mmap(td, &bsd_args);
#ifdef DEBUG
if (ldebug(mmap))
printf("-> %s() return: 0x%x (0x%08x)\n",
__func__, error, (u_int)td->td_retval[0]);
#endif
return (error);
}
int
linux_mprotect(struct thread *td, struct linux_mprotect_args *uap)
{
struct mprotect_args bsd_args;
bsd_args.addr = uap->addr;
bsd_args.len = uap->len;
bsd_args.prot = uap->prot;
if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
bsd_args.prot |= PROT_READ | PROT_EXEC;
return (sys_mprotect(td, &bsd_args));
return (linux_mprotect_common(td, PTROUT(uap->addr), uap->len, uap->prot));
}
int

2
sys/modules/linux/Makefile
View File

@ -30,7 +30,7 @@ SRCS+= opt_apic.h
OBJS= ${VDSO}.so
.if ${MACHINE_CPUARCH} == "i386"
SRCS+= linux_ptrace.c imgact_linux.c linux_util.c linux_mib.c \
SRCS+= linux_ptrace.c imgact_linux.c linux_util.c linux_mib.c linux_mmap.c \
linux_emul.c opt_cpu.h linux.c
.endif

2
sys/modules/linux_common/Makefile
View File

@ -3,7 +3,7 @@
.PATH: ${.CURDIR}/../../compat/linux
KMOD= linux_common
SRCS= linux_common.c linux_mib.c linux_util.c linux_emul.c \
SRCS= linux_common.c linux_mib.c linux_mmap.c linux_util.c linux_emul.c \
linux.c opt_compat.h device_if.h vnode_if.h bus_if.h
EXPORT_SYMS=