The struct snd_timer_tread will use 'timespec' type variables to record timestamp, which is not year 2038 safe on 32bits system.
Since the struct snd_timer_tread is passed through read() rather than ioctl(), and the read syscall has no command number that lets us pick between the 32-bit or 64-bit version of this structure. Thus we introduced one new command SNDRV_TIMER_IOCTL_TREAD64 and new struct snd_timer_tread64 replacing timespec with s64 type to handle 64bit time_t. Also add one struct compat_snd_timer_tread64_x86_32 to handle 64bit time_t with 32bit alignment. That means we will set tu->tread = TREAD_FORMAT_64BIT when user space has a 64bit time_t, then we will copy to user with struct snd_timer_tread64. For x86_32 mode, we will set tu->tread = TREAD_FORMAT_TIME32_X86 to copy struct compat_snd_timer_tread64_x86_32 for user. Otherwise we will use 32bit time_t variables when copying to user. Moreover this patch replaces timespec type with timespec64 type and related y2038 safe APIs. Signed-off-by: Baolin Wang <[email protected]> --- include/uapi/sound/asound.h | 11 ++- sound/core/timer.c | 173 ++++++++++++++++++++++++++++++++++--------- sound/core/timer_compat.c | 10 ++- 3 files changed, 157 insertions(+), 37 deletions(-) diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h index fabb283..4c74f52 100644 --- a/include/uapi/sound/asound.h +++ b/include/uapi/sound/asound.h @@ -760,7 +760,7 @@ struct snd_timer_status { #define SNDRV_TIMER_IOCTL_PVERSION _IOR('T', 0x00, int) #define SNDRV_TIMER_IOCTL_NEXT_DEVICE _IOWR('T', 0x01, struct snd_timer_id) -#define SNDRV_TIMER_IOCTL_TREAD _IOW('T', 0x02, int) +#define SNDRV_TIMER_IOCTL_TREAD_OLD _IOW('T', 0x02, int) #define SNDRV_TIMER_IOCTL_GINFO _IOWR('T', 0x03, struct snd_timer_ginfo) #define SNDRV_TIMER_IOCTL_GPARAMS _IOW('T', 0x04, struct snd_timer_gparams) #define SNDRV_TIMER_IOCTL_GSTATUS _IOWR('T', 0x05, struct snd_timer_gstatus) @@ -773,6 +773,15 @@ struct snd_timer_status { #define SNDRV_TIMER_IOCTL_STOP _IO('T', 0xa1) #define SNDRV_TIMER_IOCTL_CONTINUE _IO('T', 0xa2) #define SNDRV_TIMER_IOCTL_PAUSE _IO('T', 0xa3) +#define SNDRV_TIMER_IOCTL_TREAD64 _IOW('T', 0xa4, int) + +#if __BITS_PER_LONG == 64 +#define SNDRV_TIMER_IOCTL_TREAD SNDRV_TIMER_IOCTL_TREAD_OLD +#else +#define SNDRV_TIMER_IOCTL_TREAD ((sizeof(__kernel_long_t) > sizeof(time_t)) ? \ + SNDRV_TIMER_IOCTL_TREAD_OLD : \ + SNDRV_TIMER_IOCTL_TREAD64) +#endif struct snd_timer_read { unsigned int resolution; diff --git a/sound/core/timer.c b/sound/core/timer.c index 9168365..ba6c09e 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -58,6 +58,30 @@ MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER); MODULE_ALIAS("devname:snd/timer"); +enum timer_tread_format { + TREAD_FORMAT_NONE = 0, + TREAD_FORMAT_64BIT, + TREAD_FORMAT_TIME64, + TREAD_FORMAT_TIME32_X86, + TREAD_FORMAT_TIME32, +}; + +struct snd_timer_tread64 { + int event; + u32 pad1; + s64 tstamp_sec; + s64 tstamp_nsec; + unsigned int val; + u32 pad2; +}; + +struct compat_snd_timer_tread64_x86_32 { + int event; + s64 tstamp_sec; + s64 tstamp_nsec; + unsigned int val; +} __packed; + struct snd_timer_user { struct snd_timer_instance *timeri; int tread; /* enhanced read with timestamps and events */ @@ -69,7 +93,7 @@ struct snd_timer_user { int queue_size; bool disconnected; struct snd_timer_read *queue; - struct snd_timer_tread *tqueue; + struct snd_timer_tread64 *tqueue; spinlock_t qlock; unsigned long last_resolution; unsigned int filter; @@ -1262,7 +1286,7 @@ static void snd_timer_user_interrupt(struct snd_timer_instance *timeri, } static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu, - struct snd_timer_tread *tread) + struct snd_timer_tread64 *tread) { if (tu->qused >= tu->queue_size) { tu->overrun++; @@ -1279,7 +1303,7 @@ static void snd_timer_user_ccallback(struct snd_timer_instance *timeri, unsigned long resolution) { struct snd_timer_user *tu = timeri->callback_data; - struct snd_timer_tread r1; + struct snd_timer_tread64 r1; unsigned long flags; if (event >= SNDRV_TIMER_EVENT_START && @@ -1289,7 +1313,8 @@ static void snd_timer_user_ccallback(struct snd_timer_instance *timeri, return; memset(&r1, 0, sizeof(r1)); r1.event = event; - r1.tstamp = timespec64_to_timespec(*tstamp); + r1.tstamp_sec = tstamp->tv_sec; + r1.tstamp_nsec = tstamp->tv_nsec; r1.val = resolution; spin_lock_irqsave(&tu->qlock, flags); snd_timer_user_append_to_tqueue(tu, &r1); @@ -1311,7 +1336,7 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri, unsigned long ticks) { struct snd_timer_user *tu = timeri->callback_data; - struct snd_timer_tread *r, r1; + struct snd_timer_tread64 *r, r1; struct timespec64 tstamp; int prev, append = 0; @@ -1332,7 +1357,8 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri, if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) && tu->last_resolution != resolution) { r1.event = SNDRV_TIMER_EVENT_RESOLUTION; - r1.tstamp = timespec64_to_timespec(tstamp); + r1.tstamp_sec = tstamp.tv_sec; + r1.tstamp_nsec = tstamp.tv_nsec; r1.val = resolution; snd_timer_user_append_to_tqueue(tu, &r1); tu->last_resolution = resolution; @@ -1346,14 +1372,16 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri, prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1; r = &tu->tqueue[prev]; if (r->event == SNDRV_TIMER_EVENT_TICK) { - r->tstamp = timespec64_to_timespec(tstamp); + r->tstamp_sec = tstamp.tv_sec; + r->tstamp_nsec = tstamp.tv_nsec; r->val += ticks; append++; goto __wake; } } r1.event = SNDRV_TIMER_EVENT_TICK; - r1.tstamp = timespec64_to_timespec(tstamp); + r1.tstamp_sec = tstamp.tv_sec; + r1.tstamp_nsec = tstamp.tv_nsec; r1.val = ticks; snd_timer_user_append_to_tqueue(tu, &r1); append++; @@ -1368,7 +1396,7 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri, static int realloc_user_queue(struct snd_timer_user *tu, int size) { struct snd_timer_read *queue = NULL; - struct snd_timer_tread *tqueue = NULL; + struct snd_timer_tread64 *tqueue = NULL; if (tu->tread) { tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL); @@ -1797,11 +1825,11 @@ static int snd_timer_user_params(struct file *file, tu->qhead = tu->qtail = tu->qused = 0; if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) { if (tu->tread) { - struct snd_timer_tread tread; + struct snd_timer_tread64 tread; memset(&tread, 0, sizeof(tread)); tread.event = SNDRV_TIMER_EVENT_EARLY; - tread.tstamp.tv_sec = 0; - tread.tstamp.tv_nsec = 0; + tread.tstamp_sec = 0; + tread.tstamp_nsec = 0; tread.val = 0; snd_timer_user_append_to_tqueue(tu, &tread); } else { @@ -1919,6 +1947,39 @@ static int snd_timer_user_pause(struct file *file) return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0; } +static int snd_timer_user_tread(void __user *argp, struct snd_timer_user *tu, + unsigned int cmd, bool compat) +{ + int __user *p = argp; + int xarg, old_tread; + + if (tu->timeri) /* too late */ + return -EBUSY; + if (get_user(xarg, p)) + return -EFAULT; + + old_tread = tu->tread; + + if (!xarg) + tu->tread = TREAD_FORMAT_NONE; + else if (!IS_ENABLED(CONFIG_64BITS) && !compat) + tu->tread = TREAD_FORMAT_64BIT; + else if (cmd == SNDRV_TIMER_IOCTL_TREAD64) + tu->tread = TREAD_FORMAT_TIME64; + else if (IS_ENABLED(CONFIG_X86)) + tu->tread = TREAD_FORMAT_TIME32_X86; + else + tu->tread = TREAD_FORMAT_TIME32; + + if (tu->tread != old_tread && + realloc_user_queue(tu, tu->queue_size) < 0) { + tu->tread = old_tread; + return -ENOMEM; + } + + return 0; +} + enum { SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20), SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21), @@ -1927,7 +1988,7 @@ enum { }; static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) + unsigned long arg, bool compat) { struct snd_timer_user *tu; void __user *argp = (void __user *)arg; @@ -1939,23 +2000,9 @@ static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd, return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0; case SNDRV_TIMER_IOCTL_NEXT_DEVICE: return snd_timer_user_next_device(argp); - case SNDRV_TIMER_IOCTL_TREAD: - { - int xarg, old_tread; - - if (tu->timeri) /* too late */ - return -EBUSY; - if (get_user(xarg, p)) - return -EFAULT; - old_tread = tu->tread; - tu->tread = xarg ? 1 : 0; - if (tu->tread != old_tread && - realloc_user_queue(tu, tu->queue_size) < 0) { - tu->tread = old_tread; - return -ENOMEM; - } - return 0; - } + case SNDRV_TIMER_IOCTL_TREAD_OLD: + case SNDRV_TIMER_IOCTL_TREAD64: + return snd_timer_user_tread(argp, tu, cmd, compat); case SNDRV_TIMER_IOCTL_GINFO: return snd_timer_user_ginfo(file, argp); case SNDRV_TIMER_IOCTL_GPARAMS: @@ -1995,7 +2042,7 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd, long ret; mutex_lock(&tu->ioctl_lock); - ret = __snd_timer_user_ioctl(file, cmd, arg); + ret = __snd_timer_user_ioctl(file, cmd, arg, false); mutex_unlock(&tu->ioctl_lock); return ret; } @@ -2017,7 +2064,24 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer, int err = 0; tu = file->private_data; - unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read); + switch (tu->tread) { + case TREAD_FORMAT_TIME32_X86: + unit = sizeof(struct compat_snd_timer_tread64_x86_32); + break; + case TREAD_FORMAT_64BIT: + case TREAD_FORMAT_TIME64: + unit = sizeof(struct snd_timer_tread64); + break; + case TREAD_FORMAT_TIME32: + unit = sizeof(struct snd_timer_tread); + break; + case TREAD_FORMAT_NONE: + unit = sizeof(struct snd_timer_read); + break; + default: + return -ENOTSUPP; + } + mutex_lock(&tu->ioctl_lock); spin_lock_irq(&tu->qlock); while ((long)count - result >= unit) { @@ -2057,9 +2121,48 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer, spin_unlock_irq(&tu->qlock); if (tu->tread) { - if (copy_to_user(buffer, &tu->tqueue[qhead], - sizeof(struct snd_timer_tread))) - err = -EFAULT; + struct snd_timer_tread64 *tread = &tu->tqueue[qhead]; + struct snd_timer_tread tread32; + struct compat_snd_timer_tread64_x86_32 compat_tread64; + + switch (tu->tread) { + case TREAD_FORMAT_TIME32_X86: + memset(&compat_tread64, 0, sizeof(compat_tread64)); + compat_tread64 = (struct compat_snd_timer_tread64_x86_32) { + .event = tread->event, + .tstamp_sec = tread->tstamp_sec, + .tstamp_nsec = tread->tstamp_nsec, + .val = tread->val, + }; + + if (copy_to_user(buffer, &compat_tread64, + sizeof(compat_tread64))) + err = -EFAULT; + break; + case TREAD_FORMAT_64BIT: + case TREAD_FORMAT_TIME64: + if (copy_to_user(buffer, tread, + sizeof(struct snd_timer_tread64))) + err = -EFAULT; + break; + case TREAD_FORMAT_TIME32: + memset(&tread32, 0, sizeof(tread32)); + tread32 = (struct snd_timer_tread) { + .event = tread->event, + .tstamp = { + .tv_sec = tread->tstamp_sec, + .tv_nsec = tread->tstamp_nsec, + }, + .val = tread->val, + }; + + if (copy_to_user(buffer, &tread32, sizeof(tread32))) + err = -EFAULT; + break; + default: + err = -ENOTSUPP; + break; + } } else { if (copy_to_user(buffer, &tu->queue[qhead], sizeof(struct snd_timer_read))) diff --git a/sound/core/timer_compat.c b/sound/core/timer_compat.c index 3e09548..866e090 100644 --- a/sound/core/timer_compat.c +++ b/sound/core/timer_compat.c @@ -110,7 +110,15 @@ static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd, uns case SNDRV_TIMER_IOCTL_PAUSE: case SNDRV_TIMER_IOCTL_PAUSE_OLD: case SNDRV_TIMER_IOCTL_NEXT_DEVICE: - return snd_timer_user_ioctl(file, cmd, (unsigned long)argp); + { + struct snd_timer_user *tu = file->private_data; + long ret; + + mutex_lock(&tu->ioctl_lock); + ret = __snd_timer_user_ioctl(file, cmd, arg, false); + mutex_unlock(&tu->ioctl_lock); + return ret; + } case SNDRV_TIMER_IOCTL_GPARAMS32: return snd_timer_user_gparams_compat(file, argp); case SNDRV_TIMER_IOCTL_INFO32: -- 1.7.9.5
