From 81993e81a994504f4c8b97d3410c9a052cdbcc9d Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Sat, 1 Feb 2014 18:54:11 -0800 Subject: compat: Get rid of (get|put)_compat_time(val|spec) We have two APIs for compatiblity timespec/val, with confusingly similar names. compat_(get|put)_time(val|spec) *do* handle the case where COMPAT_USE_64BIT_TIME is set, whereas (get|put)_compat_time(val|spec) do not. This is an accident waiting to happen. Clean it up by favoring the full-service version; the limited version is replaced with double-underscore versions static to kernel/compat.c. A common pattern is to convert a struct timespec to kernel format in an allocation on the user stack. Unfortunately it is open-coded in several places. Since this allocation isn't actually needed if COMPAT_USE_64BIT_TIME is true (since user format == kernel format) encapsulate that whole pattern into the function compat_convert_timespec(). An equivalent function should be written for struct timeval if it is needed in the future. Finally, get rid of compat_(get|put)_timeval_convert(): each was only used once, and the latter was not even doing what the function said (no conversion actually was being done.) Moving the conversion into compat_sys_settimeofday() itself makes the code much more similar to sys_settimeofday() itself. v3: Remove unused compat_convert_timeval(). v2: Drop bogus "const" in the destination argument for compat_convert_time*(). Cc: Mauro Carvalho Chehab Cc: Alexander Viro Cc: Hans Verkuil Cc: Andrew Morton Cc: Heiko Carstens Cc: Manfred Spraul Cc: Mateusz Guzik Cc: Rafael Aquini Cc: Davidlohr Bueso Cc: Stephen Rothwell Cc: Dan Carpenter Cc: Arnd Bergmann Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Linus Torvalds Cc: Catalin Marinas Cc: Will Deacon Tested-by: H.J. Lu Signed-off-by: H. Peter Anvin --- kernel/compat.c | 108 ++++++++++++++++++++++++++++---------------------------- 1 file changed, 54 insertions(+), 54 deletions(-) (limited to 'kernel/compat.c') diff --git a/kernel/compat.c b/kernel/compat.c index 0a09e481b70b..3afc524a57ad 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -30,28 +30,6 @@ #include -/* - * Get/set struct timeval with struct timespec on the native side - */ -static int compat_get_timeval_convert(struct timespec *o, - struct compat_timeval __user *i) -{ - long usec; - - if (get_user(o->tv_sec, &i->tv_sec) || - get_user(usec, &i->tv_usec)) - return -EFAULT; - o->tv_nsec = usec * 1000; - return 0; -} - -static int compat_put_timeval_convert(struct compat_timeval __user *o, - struct timeval *i) -{ - return (put_user(i->tv_sec, &o->tv_sec) || - put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0; -} - static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp) { memset(txc, 0, sizeof(struct timex)); @@ -116,7 +94,7 @@ asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv, if (tv) { struct timeval ktv; do_gettimeofday(&ktv); - if (compat_put_timeval_convert(tv, &ktv)) + if (compat_put_timeval(&ktv, tv)) return -EFAULT; } if (tz) { @@ -130,59 +108,58 @@ asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv, asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv, struct timezone __user *tz) { - struct timespec kts; - struct timezone ktz; + struct timeval user_tv; + struct timespec new_ts; + struct timezone new_tz; if (tv) { - if (compat_get_timeval_convert(&kts, tv)) + if (compat_get_timeval(&user_tv, tv)) return -EFAULT; + new_ts.tv_sec = user_tv.tv_sec; + new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC; } if (tz) { - if (copy_from_user(&ktz, tz, sizeof(ktz))) + if (copy_from_user(&new_tz, tz, sizeof(*tz))) return -EFAULT; } - return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL); + return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL); } -int get_compat_timeval(struct timeval *tv, const struct compat_timeval __user *ctv) +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; } -EXPORT_SYMBOL_GPL(get_compat_timeval); -int put_compat_timeval(const struct timeval *tv, struct compat_timeval __user *ctv) +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; } -EXPORT_SYMBOL_GPL(put_compat_timeval); -int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts) +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; } -EXPORT_SYMBOL_GPL(get_compat_timespec); -int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts) +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; } -EXPORT_SYMBOL_GPL(put_compat_timespec); 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 get_compat_timeval(tv, utv); + return __compat_get_timeval(tv, utv); } EXPORT_SYMBOL_GPL(compat_get_timeval); @@ -191,7 +168,7 @@ 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 put_compat_timeval(tv, utv); + return __compat_put_timeval(tv, utv); } EXPORT_SYMBOL_GPL(compat_put_timeval); @@ -200,7 +177,7 @@ 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 get_compat_timespec(ts, uts); + return __compat_get_timespec(ts, uts); } EXPORT_SYMBOL_GPL(compat_get_timespec); @@ -209,10 +186,33 @@ 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 put_compat_timespec(ts, uts); + return __compat_put_timespec(ts, uts); } EXPORT_SYMBOL_GPL(compat_put_timespec); +int compat_convert_timespec(struct timespec __user **kts, + const void __user *cts) +{ + struct timespec ts; + struct timespec __user *uts; + + if (!cts || COMPAT_USE_64BIT_TIME) { + *kts = (struct timespec __user *)cts; + return 0; + } + + uts = compat_alloc_user_space(sizeof(ts)); + if (!uts) + return -EFAULT; + if (compat_get_timespec(&ts, cts)) + return -EFAULT; + if (copy_to_user(uts, &ts, sizeof(ts))) + return -EFAULT; + + *kts = uts; + return 0; +} + static long compat_nanosleep_restart(struct restart_block *restart) { struct compat_timespec __user *rmtp; @@ -229,7 +229,7 @@ static long compat_nanosleep_restart(struct restart_block *restart) if (ret) { rmtp = restart->nanosleep.compat_rmtp; - if (rmtp && put_compat_timespec(&rmt, rmtp)) + if (rmtp && compat_put_timespec(&rmt, rmtp)) return -EFAULT; } @@ -243,7 +243,7 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp, mm_segment_t oldfs; long ret; - if (get_compat_timespec(&tu, rqtp)) + if (compat_get_timespec(&tu, rqtp)) return -EFAULT; if (!timespec_valid(&tu)) @@ -263,7 +263,7 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp, restart->fn = compat_nanosleep_restart; restart->nanosleep.compat_rmtp = rmtp; - if (rmtp && put_compat_timespec(&rmt, rmtp)) + if (rmtp && compat_put_timespec(&rmt, rmtp)) return -EFAULT; } @@ -647,8 +647,8 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len, int get_compat_itimerspec(struct itimerspec *dst, const struct compat_itimerspec __user *src) { - if (get_compat_timespec(&dst->it_interval, &src->it_interval) || - get_compat_timespec(&dst->it_value, &src->it_value)) + if (__compat_get_timespec(&dst->it_interval, &src->it_interval) || + __compat_get_timespec(&dst->it_value, &src->it_value)) return -EFAULT; return 0; } @@ -656,8 +656,8 @@ int get_compat_itimerspec(struct itimerspec *dst, int put_compat_itimerspec(struct compat_itimerspec __user *dst, const struct itimerspec *src) { - if (put_compat_timespec(&src->it_interval, &dst->it_interval) || - put_compat_timespec(&src->it_value, &dst->it_value)) + if (__compat_put_timespec(&src->it_interval, &dst->it_interval) || + __compat_put_timespec(&src->it_value, &dst->it_value)) return -EFAULT; return 0; } @@ -727,7 +727,7 @@ long compat_sys_clock_settime(clockid_t which_clock, mm_segment_t oldfs; struct timespec ts; - if (get_compat_timespec(&ts, tp)) + if (compat_get_timespec(&ts, tp)) return -EFAULT; oldfs = get_fs(); set_fs(KERNEL_DS); @@ -749,7 +749,7 @@ long compat_sys_clock_gettime(clockid_t which_clock, err = sys_clock_gettime(which_clock, (struct timespec __user *) &ts); set_fs(oldfs); - if (!err && put_compat_timespec(&ts, tp)) + if (!err && compat_put_timespec(&ts, tp)) return -EFAULT; return err; } @@ -789,7 +789,7 @@ long compat_sys_clock_getres(clockid_t which_clock, err = sys_clock_getres(which_clock, (struct timespec __user *) &ts); set_fs(oldfs); - if (!err && tp && put_compat_timespec(&ts, tp)) + if (!err && tp && compat_put_timespec(&ts, tp)) return -EFAULT; return err; } @@ -808,7 +808,7 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart) set_fs(oldfs); if ((err == -ERESTART_RESTARTBLOCK) && rmtp && - put_compat_timespec(&tu, rmtp)) + compat_put_timespec(&tu, rmtp)) return -EFAULT; if (err == -ERESTART_RESTARTBLOCK) { @@ -827,7 +827,7 @@ long compat_sys_clock_nanosleep(clockid_t which_clock, int flags, struct timespec in, out; struct restart_block *restart; - if (get_compat_timespec(&in, rqtp)) + if (compat_get_timespec(&in, rqtp)) return -EFAULT; oldfs = get_fs(); @@ -838,7 +838,7 @@ long compat_sys_clock_nanosleep(clockid_t which_clock, int flags, set_fs(oldfs); if ((err == -ERESTART_RESTARTBLOCK) && rmtp && - put_compat_timespec(&out, rmtp)) + compat_put_timespec(&out, rmtp)) return -EFAULT; if (err == -ERESTART_RESTARTBLOCK) { @@ -1130,7 +1130,7 @@ COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval, set_fs(KERNEL_DS); ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t); set_fs(old_fs); - if (put_compat_timespec(&t, interval)) + if (compat_put_timespec(&t, interval)) return -EFAULT; return ret; } -- cgit From dce44e03b0a3448ad11ac6c6e0cbe299e0400791 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Sun, 2 Feb 2014 17:57:28 -0800 Subject: compat: Fix sparse address space warnings In compat_sys_old_getrlimit() we pass a kernel pointer to sys_old_getrlimit() inside a set_fs() bracket. This is okay, so we can safely cast the affected pointer to __user. In compat_clock_nanosleep_restart(), the variable "rmtp" holds a user pointer. Annotate it as such. Both of these warnings are ancient, but were reported by Fengguang Wu's test system due to other changes. Signed-off-by: H. Peter Anvin Cc: Toyo Abe Link: http://lkml.kernel.org/n/tip-507h7cq5e45eg6ygtykon3bf@git.kernel.org --- kernel/compat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/compat.c') diff --git a/kernel/compat.c b/kernel/compat.c index 3afc524a57ad..7076b57fa52e 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -451,7 +451,7 @@ asmlinkage long compat_sys_old_getrlimit(unsigned int resource, mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); - ret = sys_old_getrlimit(resource, &r); + ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r); set_fs(old_fs); if (!ret) { @@ -799,7 +799,7 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart) long err; mm_segment_t oldfs; struct timespec tu; - struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp; + struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp; restart->nanosleep.rmtp = (struct timespec __user *) &tu; oldfs = get_fs(); -- cgit