/* * 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; } static int __compat_get_timespec64(struct timespec64 *ts64, const struct compat_timespec __user *cts) { struct compat_timespec ts; int ret; ret = copy_from_user(&ts, cts, sizeof(ts)); if (ret) return -EFAULT; ts64->tv_sec = ts.tv_sec; ts64->tv_nsec = ts.tv_nsec; return 0; } static int __compat_put_timespec64(const struct timespec64 *ts64, struct compat_timespec __user *cts) { struct compat_timespec ts = { .tv_sec = ts64->tv_sec, .tv_nsec = ts64->tv_nsec }; return copy_to_user(cts, &ts, sizeof(ts)) ? -EFAULT : 0; } int compat_get_timespec64(struct timespec64 *ts, const void __user *uts) { if (COMPAT_USE_64BIT_TIME) return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0; else return __compat_get_timespec64(ts, uts); } EXPORT_SYMBOL_GPL(compat_get_timespec64); int compat_put_timespec64(const struct timespec64 *ts, void __user *uts) { if (COMPAT_USE_64BIT_TIME) return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0; else return __compat_put_timespec64(ts, uts); } EXPORT_SYMBOL_GPL(compat_put_timespec64); 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; } int get_compat_itimerspec64(struct itimerspec64 *its, const struct compat_itimerspec __user *uits) { if (__compat_get_timespec64(&its->it_interval, &uits->it_interval) || __compat_get_timespec64(&its->it_value, &uits->it_value)) return -EFAULT; return 0; } EXPORT_SYMBOL_GPL(get_compat_itimerspec64); int put_compat_itimerspec64(const struct itimerspec64 *its, struct compat_itimerspec __user *uits) { if (__compat_put_timespec64(&its->it_interval, &uits->it_interval) || __compat_put_timespec64(&its->it_value, &uits->it_value)) return -EFAULT; return 0; } EXPORT_SYMBOL_GPL(put_compat_itimerspec64); /* * 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 (!access_ok(VERIFY_READ, umask, bitmap_size / 8)) return -EFAULT; user_access_begin(); 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 (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8)) return -EFAULT; user_access_begin(); 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);