'struct snd_timer_gparams' includes some members with 'unsigned long', therefore its size differs depending on data models of architecture. As a result, x86/x32 applications fail to execute ioctl(2) with SNDRV_TIMER_GPARAMS command on x86_64 machine.
This commit fixes this bug by adding a pair of structure and ioctl command for the compatibility.
Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp --- sound/core/timer.c | 20 +++++++++++++------- sound/core/timer_compat.c | 30 +++++++++++++++++++++++++++++- 2 files changed, 42 insertions(+), 8 deletions(-)
diff --git a/sound/core/timer.c b/sound/core/timer.c index aa1b15c..ea4d999 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -1502,17 +1502,13 @@ static int snd_timer_user_ginfo(struct file *file, return err; }
-static int snd_timer_user_gparams(struct file *file, - struct snd_timer_gparams __user *_gparams) +static int timer_set_gparams(struct snd_timer_gparams *gparams) { - struct snd_timer_gparams gparams; struct snd_timer *t; int err;
- if (copy_from_user(&gparams, _gparams, sizeof(gparams))) - return -EFAULT; mutex_lock(®ister_mutex); - t = snd_timer_find(&gparams.tid); + t = snd_timer_find(&gparams->tid); if (!t) { err = -ENODEV; goto _error; @@ -1525,12 +1521,22 @@ static int snd_timer_user_gparams(struct file *file, err = -ENOSYS; goto _error; } - err = t->hw.set_period(t, gparams.period_num, gparams.period_den); + err = t->hw.set_period(t, gparams->period_num, gparams->period_den); _error: mutex_unlock(®ister_mutex); return err; }
+static int snd_timer_user_gparams(struct file *file, + struct snd_timer_gparams __user *_gparams) +{ + struct snd_timer_gparams gparams; + + if (copy_from_user(&gparams, _gparams, sizeof(gparams))) + return -EFAULT; + return timer_set_gparams(&gparams); +} + static int snd_timer_user_gstatus(struct file *file, struct snd_timer_gstatus __user *_gstatus) { diff --git a/sound/core/timer_compat.c b/sound/core/timer_compat.c index 2e90822..6a437eb 100644 --- a/sound/core/timer_compat.c +++ b/sound/core/timer_compat.c @@ -22,6 +22,19 @@
#include <linux/compat.h>
+/* + * ILP32/LP64 has different size for 'long' type. Additionally, the size + * of storage alignment differs depending on architectures. Here, '__packed' + * qualifier is used so that the size of this structure is multiple of 4 and + * it fits to any architectures with 32 bit storage alignment. + */ +struct snd_timer_gparams32 { + struct snd_timer_id tid; + u32 period_num; + u32 period_den; + unsigned char reserved[32]; +} __packed; + struct snd_timer_info32 { u32 flags; s32 card; @@ -32,6 +45,19 @@ struct snd_timer_info32 { unsigned char reserved[64]; };
+static int snd_timer_user_gparams_compat(struct file *file, + struct snd_timer_gparams32 __user *user) +{ + struct snd_timer_gparams gparams; + + if (copy_from_user(&gparams.tid, &user->tid, sizeof(gparams.tid)) || + get_user(gparams.period_num, &user->period_num) || + get_user(gparams.period_den, &user->period_den)) + return -EFAULT; + + return timer_set_gparams(&gparams); +} + static int snd_timer_user_info_compat(struct file *file, struct snd_timer_info32 __user *_info) { @@ -99,6 +125,7 @@ static int snd_timer_user_status_compat(struct file *file, */
enum { + SNDRV_TIMER_IOCTL_GPARAMS32 = _IOW('T', 0x04, struct snd_timer_gparams32), SNDRV_TIMER_IOCTL_INFO32 = _IOR('T', 0x11, struct snd_timer_info32), SNDRV_TIMER_IOCTL_STATUS32 = _IOW('T', 0x14, struct snd_timer_status32), #ifdef CONFIG_X86_X32 @@ -114,7 +141,6 @@ static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd, uns case SNDRV_TIMER_IOCTL_PVERSION: case SNDRV_TIMER_IOCTL_TREAD: case SNDRV_TIMER_IOCTL_GINFO: - case SNDRV_TIMER_IOCTL_GPARAMS: case SNDRV_TIMER_IOCTL_GSTATUS: case SNDRV_TIMER_IOCTL_SELECT: case SNDRV_TIMER_IOCTL_PARAMS: @@ -128,6 +154,8 @@ static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd, uns case SNDRV_TIMER_IOCTL_PAUSE_OLD: case SNDRV_TIMER_IOCTL_NEXT_DEVICE: return snd_timer_user_ioctl(file, cmd, (unsigned long)argp); + case SNDRV_TIMER_IOCTL_GPARAMS32: + return snd_timer_user_gparams_compat(file, argp); case SNDRV_TIMER_IOCTL_INFO32: return snd_timer_user_info_compat(file, argp); case SNDRV_TIMER_IOCTL_STATUS32: