linux-stable/arch/powerpc/include/asm/compat.h
Paul Mackerras 573ebfa660 powerpc: Increase stack redzone for 64-bit userspace to 512 bytes
The new ELFv2 little-endian ABI increases the stack redzone -- the
area below the stack pointer that can be used for storing data --
from 288 bytes to 512 bytes.  This means that we need to allow more
space on the user stack when delivering a signal to a 64-bit process.

To make the code a bit clearer, we define new USER_REDZONE_SIZE and
KERNEL_REDZONE_SIZE symbols in ptrace.h.  For now, we leave the
kernel redzone size at 288 bytes, since increasing it to 512 bytes
would increase the size of interrupt stack frames correspondingly.

Gcc currently only makes use of 288 bytes of redzone even when
compiling for the new little-endian ABI, and the kernel cannot
currently be compiled with the new ABI anyway.

In the future, hopefully gcc will provide an option to control the
amount of redzone used, and then we could reduce it even more.

This also changes the code in arch_compat_alloc_user_space() to
preserve the expanded redzone.  It is not clear why this function would
ever be used on a 64-bit process, though.

Signed-off-by: Paul Mackerras <paulus@samba.org>
CC: <stable@vger.kernel.org> [v3.13]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-02-28 18:06:26 +11:00

280 lines
6 KiB
C

#ifndef _ASM_POWERPC_COMPAT_H
#define _ASM_POWERPC_COMPAT_H
#ifdef __KERNEL__
/*
* Architecture specific compatibility types
*/
#include <linux/types.h>
#include <linux/sched.h>
#define COMPAT_USER_HZ 100
#define COMPAT_UTS_MACHINE "ppc\0\0"
typedef u32 compat_size_t;
typedef s32 compat_ssize_t;
typedef s32 compat_time_t;
typedef s32 compat_clock_t;
typedef s32 compat_pid_t;
typedef u32 __compat_uid_t;
typedef u32 __compat_gid_t;
typedef u32 __compat_uid32_t;
typedef u32 __compat_gid32_t;
typedef u32 compat_mode_t;
typedef u32 compat_ino_t;
typedef u32 compat_dev_t;
typedef s32 compat_off_t;
typedef s64 compat_loff_t;
typedef s16 compat_nlink_t;
typedef u16 compat_ipc_pid_t;
typedef s32 compat_daddr_t;
typedef u32 compat_caddr_t;
typedef __kernel_fsid_t compat_fsid_t;
typedef s32 compat_key_t;
typedef s32 compat_timer_t;
typedef s32 compat_int_t;
typedef s32 compat_long_t;
typedef s64 compat_s64;
typedef u32 compat_uint_t;
typedef u32 compat_ulong_t;
typedef u64 compat_u64;
typedef u32 compat_uptr_t;
struct compat_timespec {
compat_time_t tv_sec;
s32 tv_nsec;
};
struct compat_timeval {
compat_time_t tv_sec;
s32 tv_usec;
};
struct compat_stat {
compat_dev_t st_dev;
compat_ino_t st_ino;
compat_mode_t st_mode;
compat_nlink_t st_nlink;
__compat_uid32_t st_uid;
__compat_gid32_t st_gid;
compat_dev_t st_rdev;
compat_off_t st_size;
compat_off_t st_blksize;
compat_off_t st_blocks;
compat_time_t st_atime;
u32 st_atime_nsec;
compat_time_t st_mtime;
u32 st_mtime_nsec;
compat_time_t st_ctime;
u32 st_ctime_nsec;
u32 __unused4[2];
};
struct compat_flock {
short l_type;
short l_whence;
compat_off_t l_start;
compat_off_t l_len;
compat_pid_t l_pid;
};
#define F_GETLK64 12 /* using 'struct flock64' */
#define F_SETLK64 13
#define F_SETLKW64 14
struct compat_flock64 {
short l_type;
short l_whence;
compat_loff_t l_start;
compat_loff_t l_len;
compat_pid_t l_pid;
};
struct compat_statfs {
int f_type;
int f_bsize;
int f_blocks;
int f_bfree;
int f_bavail;
int f_files;
int f_ffree;
compat_fsid_t f_fsid;
int f_namelen; /* SunOS ignores this field. */
int f_frsize;
int f_flags;
int f_spare[4];
};
#define COMPAT_RLIM_OLD_INFINITY 0x7fffffff
#define COMPAT_RLIM_INFINITY 0xffffffff
typedef u32 compat_old_sigset_t;
#define _COMPAT_NSIG 64
#define _COMPAT_NSIG_BPW 32
typedef u32 compat_sigset_word;
typedef union compat_sigval {
compat_int_t sival_int;
compat_uptr_t sival_ptr;
} compat_sigval_t;
#define SI_PAD_SIZE32 (128/sizeof(int) - 3)
typedef struct compat_siginfo {
int si_signo;
int si_errno;
int si_code;
union {
int _pad[SI_PAD_SIZE32];
/* kill() */
struct {
compat_pid_t _pid; /* sender's pid */
__compat_uid_t _uid; /* sender's uid */
} _kill;
/* POSIX.1b timers */
struct {
compat_timer_t _tid; /* timer id */
int _overrun; /* overrun count */
compat_sigval_t _sigval; /* same as below */
int _sys_private; /* not to be passed to user */
} _timer;
/* POSIX.1b signals */
struct {
compat_pid_t _pid; /* sender's pid */
__compat_uid_t _uid; /* sender's uid */
compat_sigval_t _sigval;
} _rt;
/* SIGCHLD */
struct {
compat_pid_t _pid; /* which child */
__compat_uid_t _uid; /* sender's uid */
int _status; /* exit code */
compat_clock_t _utime;
compat_clock_t _stime;
} _sigchld;
/* SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGEMT */
struct {
unsigned int _addr; /* faulting insn/memory ref. */
} _sigfault;
/* SIGPOLL */
struct {
int _band; /* POLL_IN, POLL_OUT, POLL_MSG */
int _fd;
} _sigpoll;
} _sifields;
} compat_siginfo_t;
#define COMPAT_OFF_T_MAX 0x7fffffff
#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL
/*
* A pointer passed in from user mode. This should not
* be used for syscall parameters, just declare them
* as pointers because the syscall entry code will have
* appropriately converted them already.
*/
static inline void __user *compat_ptr(compat_uptr_t uptr)
{
return (void __user *)(unsigned long)uptr;
}
static inline compat_uptr_t ptr_to_compat(void __user *uptr)
{
return (u32)(unsigned long)uptr;
}
static inline void __user *arch_compat_alloc_user_space(long len)
{
struct pt_regs *regs = current->thread.regs;
unsigned long usp = regs->gpr[1];
/*
* We can't access below the stack pointer in the 32bit ABI and
* can access 288 bytes in the 64bit big-endian ABI,
* or 512 bytes with the new ELFv2 little-endian ABI.
*/
if (!is_32bit_task())
usp -= USER_REDZONE_SIZE;
return (void __user *) (usp - len);
}
/*
* ipc64_perm is actually 32/64bit clean but since the compat layer refers to
* it we may as well define it.
*/
struct compat_ipc64_perm {
compat_key_t key;
__compat_uid_t uid;
__compat_gid_t gid;
__compat_uid_t cuid;
__compat_gid_t cgid;
compat_mode_t mode;
unsigned int seq;
unsigned int __pad2;
unsigned long __unused1; /* yes they really are 64bit pads */
unsigned long __unused2;
};
struct compat_semid64_ds {
struct compat_ipc64_perm sem_perm;
unsigned int __unused1;
compat_time_t sem_otime;
unsigned int __unused2;
compat_time_t sem_ctime;
compat_ulong_t sem_nsems;
compat_ulong_t __unused3;
compat_ulong_t __unused4;
};
struct compat_msqid64_ds {
struct compat_ipc64_perm msg_perm;
unsigned int __unused1;
compat_time_t msg_stime;
unsigned int __unused2;
compat_time_t msg_rtime;
unsigned int __unused3;
compat_time_t msg_ctime;
compat_ulong_t msg_cbytes;
compat_ulong_t msg_qnum;
compat_ulong_t msg_qbytes;
compat_pid_t msg_lspid;
compat_pid_t msg_lrpid;
compat_ulong_t __unused4;
compat_ulong_t __unused5;
};
struct compat_shmid64_ds {
struct compat_ipc64_perm shm_perm;
unsigned int __unused1;
compat_time_t shm_atime;
unsigned int __unused2;
compat_time_t shm_dtime;
unsigned int __unused3;
compat_time_t shm_ctime;
unsigned int __unused4;
compat_size_t shm_segsz;
compat_pid_t shm_cpid;
compat_pid_t shm_lpid;
compat_ulong_t shm_nattch;
compat_ulong_t __unused5;
compat_ulong_t __unused6;
};
static inline int is_compat_task(void)
{
return is_32bit_task();
}
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_COMPAT_H */