diff options
Diffstat (limited to 'kernel/compat.c')
| -rw-r--r-- | kernel/compat.c | 444 |
1 files changed, 444 insertions, 0 deletions
diff --git a/kernel/compat.c b/kernel/compat.c new file mode 100644 index 000000000..e4548a9e9 --- /dev/null +++ b/kernel/compat.c @@ -0,0 +1,444 @@ +/* + * linux/kernel/compat.c + * + * Kernel compatibililty routines for e.g. 32 bit syscall support + * on 64 bit kernels. + * + * Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/linkage.h> +#include <linux/compat.h> +#include <linux/errno.h> +#include <linux/time.h> +#include <linux/signal.h> +#include <linux/sched.h> /* for MAX_SCHEDULE_TIMEOUT */ +#include <linux/syscalls.h> +#include <linux/unistd.h> +#include <linux/security.h> +#include <linux/timex.h> +#include <linux/export.h> +#include <linux/migrate.h> +#include <linux/posix-timers.h> +#include <linux/times.h> +#include <linux/ptrace.h> +#include <linux/gfp.h> + +#include <linux/uaccess.h> + +int compat_get_timex(struct timex *txc, const struct compat_timex __user *utp) +{ + struct compat_timex tx32; + + memset(txc, 0, sizeof(struct timex)); + if (copy_from_user(&tx32, utp, sizeof(struct compat_timex))) + return -EFAULT; + + txc->modes = tx32.modes; + txc->offset = tx32.offset; + txc->freq = tx32.freq; + txc->maxerror = tx32.maxerror; + txc->esterror = tx32.esterror; + txc->status = tx32.status; + txc->constant = tx32.constant; + txc->precision = tx32.precision; + txc->tolerance = tx32.tolerance; + txc->time.tv_sec = tx32.time.tv_sec; + txc->time.tv_usec = tx32.time.tv_usec; + txc->tick = tx32.tick; + txc->ppsfreq = tx32.ppsfreq; + txc->jitter = tx32.jitter; + txc->shift = tx32.shift; + txc->stabil = tx32.stabil; + txc->jitcnt = tx32.jitcnt; + txc->calcnt = tx32.calcnt; + txc->errcnt = tx32.errcnt; + txc->stbcnt = tx32.stbcnt; + + return 0; +} + +int compat_put_timex(struct compat_timex __user *utp, const struct timex *txc) +{ + struct compat_timex tx32; + + memset(&tx32, 0, sizeof(struct compat_timex)); + tx32.modes = txc->modes; + tx32.offset = txc->offset; + tx32.freq = txc->freq; + tx32.maxerror = txc->maxerror; + tx32.esterror = txc->esterror; + tx32.status = txc->status; + tx32.constant = txc->constant; + tx32.precision = txc->precision; + tx32.tolerance = txc->tolerance; + tx32.time.tv_sec = txc->time.tv_sec; + tx32.time.tv_usec = txc->time.tv_usec; + tx32.tick = txc->tick; + tx32.ppsfreq = txc->ppsfreq; + tx32.jitter = txc->jitter; + tx32.shift = txc->shift; + tx32.stabil = txc->stabil; + tx32.jitcnt = txc->jitcnt; + tx32.calcnt = txc->calcnt; + tx32.errcnt = txc->errcnt; + tx32.stbcnt = txc->stbcnt; + tx32.tai = txc->tai; + if (copy_to_user(utp, &tx32, sizeof(struct compat_timex))) + return -EFAULT; + return 0; +} + +static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv) +{ + return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) || + __get_user(tv->tv_sec, &ctv->tv_sec) || + __get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0; +} + +static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv) +{ + return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) || + __put_user(tv->tv_sec, &ctv->tv_sec) || + __put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0; +} + +static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts) +{ + return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) || + __get_user(ts->tv_sec, &cts->tv_sec) || + __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0; +} + +static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts) +{ + return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) || + __put_user(ts->tv_sec, &cts->tv_sec) || + __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0; +} + +int compat_get_timeval(struct timeval *tv, const void __user *utv) +{ + if (COMPAT_USE_64BIT_TIME) + return copy_from_user(tv, utv, sizeof(*tv)) ? -EFAULT : 0; + else + return __compat_get_timeval(tv, utv); +} +EXPORT_SYMBOL_GPL(compat_get_timeval); + +int compat_put_timeval(const struct timeval *tv, void __user *utv) +{ + if (COMPAT_USE_64BIT_TIME) + return copy_to_user(utv, tv, sizeof(*tv)) ? -EFAULT : 0; + else + return __compat_put_timeval(tv, utv); +} +EXPORT_SYMBOL_GPL(compat_put_timeval); + +int compat_get_timespec(struct timespec *ts, const void __user *uts) +{ + if (COMPAT_USE_64BIT_TIME) + return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0; + else + return __compat_get_timespec(ts, uts); +} +EXPORT_SYMBOL_GPL(compat_get_timespec); + +int compat_put_timespec(const struct timespec *ts, void __user *uts) +{ + if (COMPAT_USE_64BIT_TIME) + return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0; + else + return __compat_put_timespec(ts, uts); +} +EXPORT_SYMBOL_GPL(compat_put_timespec); + +int get_compat_itimerval(struct itimerval *o, const struct compat_itimerval __user *i) +{ + struct compat_itimerval v32; + + if (copy_from_user(&v32, i, sizeof(struct compat_itimerval))) + return -EFAULT; + o->it_interval.tv_sec = v32.it_interval.tv_sec; + o->it_interval.tv_usec = v32.it_interval.tv_usec; + o->it_value.tv_sec = v32.it_value.tv_sec; + o->it_value.tv_usec = v32.it_value.tv_usec; + return 0; +} + +int put_compat_itimerval(struct compat_itimerval __user *o, const struct itimerval *i) +{ + struct compat_itimerval v32; + + v32.it_interval.tv_sec = i->it_interval.tv_sec; + v32.it_interval.tv_usec = i->it_interval.tv_usec; + v32.it_value.tv_sec = i->it_value.tv_sec; + v32.it_value.tv_usec = i->it_value.tv_usec; + return copy_to_user(o, &v32, sizeof(struct compat_itimerval)) ? -EFAULT : 0; +} + +#ifdef __ARCH_WANT_SYS_SIGPROCMASK + +/* + * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the + * blocked set of signals to the supplied signal set + */ +static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set) +{ + memcpy(blocked->sig, &set, sizeof(set)); +} + +COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how, + compat_old_sigset_t __user *, nset, + compat_old_sigset_t __user *, oset) +{ + old_sigset_t old_set, new_set; + sigset_t new_blocked; + + old_set = current->blocked.sig[0]; + + if (nset) { + if (get_user(new_set, nset)) + return -EFAULT; + new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP)); + + new_blocked = current->blocked; + + switch (how) { + case SIG_BLOCK: + sigaddsetmask(&new_blocked, new_set); + break; + case SIG_UNBLOCK: + sigdelsetmask(&new_blocked, new_set); + break; + case SIG_SETMASK: + compat_sig_setmask(&new_blocked, new_set); + break; + default: + return -EINVAL; + } + + set_current_blocked(&new_blocked); + } + + if (oset) { + if (put_user(old_set, oset)) + return -EFAULT; + } + + return 0; +} + +#endif + +int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru) +{ + struct compat_rusage r32; + memset(&r32, 0, sizeof(r32)); + r32.ru_utime.tv_sec = r->ru_utime.tv_sec; + r32.ru_utime.tv_usec = r->ru_utime.tv_usec; + r32.ru_stime.tv_sec = r->ru_stime.tv_sec; + r32.ru_stime.tv_usec = r->ru_stime.tv_usec; + r32.ru_maxrss = r->ru_maxrss; + r32.ru_ixrss = r->ru_ixrss; + r32.ru_idrss = r->ru_idrss; + r32.ru_isrss = r->ru_isrss; + r32.ru_minflt = r->ru_minflt; + r32.ru_majflt = r->ru_majflt; + r32.ru_nswap = r->ru_nswap; + r32.ru_inblock = r->ru_inblock; + r32.ru_oublock = r->ru_oublock; + r32.ru_msgsnd = r->ru_msgsnd; + r32.ru_msgrcv = r->ru_msgrcv; + r32.ru_nsignals = r->ru_nsignals; + r32.ru_nvcsw = r->ru_nvcsw; + r32.ru_nivcsw = r->ru_nivcsw; + if (copy_to_user(ru, &r32, sizeof(r32))) + return -EFAULT; + return 0; +} + +static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr, + unsigned len, struct cpumask *new_mask) +{ + unsigned long *k; + + if (len < cpumask_size()) + memset(new_mask, 0, cpumask_size()); + else if (len > cpumask_size()) + len = cpumask_size(); + + k = cpumask_bits(new_mask); + return compat_get_bitmap(k, user_mask_ptr, len * 8); +} + +COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid, + unsigned int, len, + compat_ulong_t __user *, user_mask_ptr) +{ + cpumask_var_t new_mask; + int retval; + + if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) + return -ENOMEM; + + retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask); + if (retval) + goto out; + + retval = sched_setaffinity(pid, new_mask); +out: + free_cpumask_var(new_mask); + return retval; +} + +COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t, pid, unsigned int, len, + compat_ulong_t __user *, user_mask_ptr) +{ + int ret; + cpumask_var_t mask; + + if ((len * BITS_PER_BYTE) < nr_cpu_ids) + return -EINVAL; + if (len & (sizeof(compat_ulong_t)-1)) + return -EINVAL; + + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) + return -ENOMEM; + + ret = sched_getaffinity(pid, mask); + if (ret == 0) { + unsigned int retlen = min(len, cpumask_size()); + + if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8)) + ret = -EFAULT; + else + ret = retlen; + } + free_cpumask_var(mask); + + return ret; +} + +/* + * We currently only need the following fields from the sigevent + * structure: sigev_value, sigev_signo, sig_notify and (sometimes + * sigev_notify_thread_id). The others are handled in user mode. + * We also assume that copying sigev_value.sival_int is sufficient + * to keep all the bits of sigev_value.sival_ptr intact. + */ +int get_compat_sigevent(struct sigevent *event, + const struct compat_sigevent __user *u_event) +{ + memset(event, 0, sizeof(*event)); + return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) || + __get_user(event->sigev_value.sival_int, + &u_event->sigev_value.sival_int) || + __get_user(event->sigev_signo, &u_event->sigev_signo) || + __get_user(event->sigev_notify, &u_event->sigev_notify) || + __get_user(event->sigev_notify_thread_id, + &u_event->sigev_notify_thread_id)) + ? -EFAULT : 0; +} + +long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask, + unsigned long bitmap_size) +{ + unsigned long nr_compat_longs; + + /* align bitmap up to nearest compat_long_t boundary */ + bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG); + nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size); + + if (!user_access_begin(VERIFY_READ, umask, bitmap_size / 8)) + return -EFAULT; + + while (nr_compat_longs > 1) { + compat_ulong_t l1, l2; + unsafe_get_user(l1, umask++, Efault); + unsafe_get_user(l2, umask++, Efault); + *mask++ = ((unsigned long)l2 << BITS_PER_COMPAT_LONG) | l1; + nr_compat_longs -= 2; + } + if (nr_compat_longs) + unsafe_get_user(*mask, umask++, Efault); + user_access_end(); + return 0; + +Efault: + user_access_end(); + return -EFAULT; +} + +long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, + unsigned long bitmap_size) +{ + unsigned long nr_compat_longs; + + /* align bitmap up to nearest compat_long_t boundary */ + bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG); + nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size); + + if (!user_access_begin(VERIFY_WRITE, umask, bitmap_size / 8)) + return -EFAULT; + + while (nr_compat_longs > 1) { + unsigned long m = *mask++; + unsafe_put_user((compat_ulong_t)m, umask++, Efault); + unsafe_put_user(m >> BITS_PER_COMPAT_LONG, umask++, Efault); + nr_compat_longs -= 2; + } + if (nr_compat_longs) + unsafe_put_user((compat_ulong_t)*mask, umask++, Efault); + user_access_end(); + return 0; +Efault: + user_access_end(); + return -EFAULT; +} + +int +get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat) +{ +#ifdef __BIG_ENDIAN + compat_sigset_t v; + if (copy_from_user(&v, compat, sizeof(compat_sigset_t))) + return -EFAULT; + switch (_NSIG_WORDS) { + case 4: set->sig[3] = v.sig[6] | (((long)v.sig[7]) << 32 ); + case 3: set->sig[2] = v.sig[4] | (((long)v.sig[5]) << 32 ); + case 2: set->sig[1] = v.sig[2] | (((long)v.sig[3]) << 32 ); + case 1: set->sig[0] = v.sig[0] | (((long)v.sig[1]) << 32 ); + } +#else + if (copy_from_user(set, compat, sizeof(compat_sigset_t))) + return -EFAULT; +#endif + return 0; +} +EXPORT_SYMBOL_GPL(get_compat_sigset); + +/* + * Allocate user-space memory for the duration of a single system call, + * in order to marshall parameters inside a compat thunk. + */ +void __user *compat_alloc_user_space(unsigned long len) +{ + void __user *ptr; + + /* If len would occupy more than half of the entire compat space... */ + if (unlikely(len > (((compat_uptr_t)~0) >> 1))) + return NULL; + + ptr = arch_compat_alloc_user_space(len); + + if (unlikely(!access_ok(VERIFY_WRITE, ptr, len))) + return NULL; + + return ptr; +} +EXPORT_SYMBOL_GPL(compat_alloc_user_space); |