[alsa-devel] [PATCH v2 2/6] ALSA: pcm: Fix ioctls for X32 ABI

Takashi Iwai tiwai at suse.de
Mon Feb 29 17:16:41 CET 2016


X32 ABI uses the 64bit timespec in addition to 64bit alignment of
64bit values.  This leads to incompatibilities in some PCM ioctls
involved with snd_pcm_channel_info, snd_pcm_status and
snd_pcm_sync_ptr structs.  Fix the PCM compat ABI for these ioctls
like the previous commit for ctl API.

Reported-by: Steven Newbury <steve at snewbury.org.uk>
Cc: <stable at vger.kernel.org> # v3.4+
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/core/pcm_compat.c | 177 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 176 insertions(+), 1 deletion(-)

diff --git a/sound/core/pcm_compat.c b/sound/core/pcm_compat.c
index 9630e9f72b7b..1f64ab0c2a95 100644
--- a/sound/core/pcm_compat.c
+++ b/sound/core/pcm_compat.c
@@ -183,6 +183,14 @@ static int snd_pcm_ioctl_channel_info_compat(struct snd_pcm_substream *substream
 	return err;
 }
 
+#ifdef CONFIG_X86_X32
+/* X32 ABI has the same struct as x86-64 for snd_pcm_channel_info */
+static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
+				     struct snd_pcm_channel_info __user *src);
+#define snd_pcm_ioctl_channel_info_x32(s, p)	\
+	snd_pcm_channel_info_user(s, p)
+#endif /* CONFIG_X86_X32 */
+
 struct snd_pcm_status32 {
 	s32 state;
 	struct compat_timespec trigger_tstamp;
@@ -243,6 +251,71 @@ static int snd_pcm_status_user_compat(struct snd_pcm_substream *substream,
 	return err;
 }
 
+#ifdef CONFIG_X86_X32
+/* X32 ABI has 64bit timespec and 64bit alignment */
+struct snd_pcm_status_x32 {
+	s32 state;
+	u32 rsvd; /* alignment */
+	struct timespec trigger_tstamp;
+	struct timespec tstamp;
+	u32 appl_ptr;
+	u32 hw_ptr;
+	s32 delay;
+	u32 avail;
+	u32 avail_max;
+	u32 overrange;
+	s32 suspended_state;
+	u32 audio_tstamp_data;
+	struct timespec audio_tstamp;
+	struct timespec driver_tstamp;
+	u32 audio_tstamp_accuracy;
+	unsigned char reserved[52-2*sizeof(struct timespec)];
+} __packed;
+
+#define put_timespec(src, dst) copy_to_user(dst, src, sizeof(*dst))
+
+static int snd_pcm_status_user_x32(struct snd_pcm_substream *substream,
+				   struct snd_pcm_status_x32 __user *src,
+				   bool ext)
+{
+	struct snd_pcm_status status;
+	int err;
+
+	memset(&status, 0, sizeof(status));
+	/*
+	 * with extension, parameters are read/write,
+	 * get audio_tstamp_data from user,
+	 * ignore rest of status structure
+	 */
+	if (ext && get_user(status.audio_tstamp_data,
+				(u32 __user *)(&src->audio_tstamp_data)))
+		return -EFAULT;
+	err = snd_pcm_status(substream, &status);
+	if (err < 0)
+		return err;
+
+	if (clear_user(src, sizeof(*src)))
+		return -EFAULT;
+	if (put_user(status.state, &src->state) ||
+	    put_timespec(&status.trigger_tstamp, &src->trigger_tstamp) ||
+	    put_timespec(&status.tstamp, &src->tstamp) ||
+	    put_user(status.appl_ptr, &src->appl_ptr) ||
+	    put_user(status.hw_ptr, &src->hw_ptr) ||
+	    put_user(status.delay, &src->delay) ||
+	    put_user(status.avail, &src->avail) ||
+	    put_user(status.avail_max, &src->avail_max) ||
+	    put_user(status.overrange, &src->overrange) ||
+	    put_user(status.suspended_state, &src->suspended_state) ||
+	    put_user(status.audio_tstamp_data, &src->audio_tstamp_data) ||
+	    put_timespec(&status.audio_tstamp, &src->audio_tstamp) ||
+	    put_timespec(&status.driver_tstamp, &src->driver_tstamp) ||
+	    put_user(status.audio_tstamp_accuracy, &src->audio_tstamp_accuracy))
+		return -EFAULT;
+
+	return err;
+}
+#endif /* CONFIG_X86_X32 */
+
 /* both for HW_PARAMS and HW_REFINE */
 static int snd_pcm_ioctl_hw_params_compat(struct snd_pcm_substream *substream,
 					  int refine, 
@@ -469,6 +542,93 @@ static int snd_pcm_ioctl_sync_ptr_compat(struct snd_pcm_substream *substream,
 	return 0;
 }
 
+#ifdef CONFIG_X86_X32
+/* X32 ABI has 64bit timespec and 64bit alignment */
+struct snd_pcm_mmap_status_x32 {
+	s32 state;
+	s32 pad1;
+	u32 hw_ptr;
+	u32 pad2; /* alignment */
+	struct timespec tstamp;
+	s32 suspended_state;
+	struct timespec audio_tstamp;
+} __packed;
+
+struct snd_pcm_mmap_control_x32 {
+	u32 appl_ptr;
+	u32 avail_min;
+};
+
+struct snd_pcm_sync_ptr_x32 {
+	u32 flags;
+	u32 rsvd; /* alignment */
+	union {
+		struct snd_pcm_mmap_status_x32 status;
+		unsigned char reserved[64];
+	} s;
+	union {
+		struct snd_pcm_mmap_control_x32 control;
+		unsigned char reserved[64];
+	} c;
+} __packed;
+
+static int snd_pcm_ioctl_sync_ptr_x32(struct snd_pcm_substream *substream,
+				      struct snd_pcm_sync_ptr_x32 __user *src)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	volatile struct snd_pcm_mmap_status *status;
+	volatile struct snd_pcm_mmap_control *control;
+	u32 sflags;
+	struct snd_pcm_mmap_control scontrol;
+	struct snd_pcm_mmap_status sstatus;
+	snd_pcm_uframes_t boundary;
+	int err;
+
+	if (snd_BUG_ON(!runtime))
+		return -EINVAL;
+
+	if (get_user(sflags, &src->flags) ||
+	    get_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
+	    get_user(scontrol.avail_min, &src->c.control.avail_min))
+		return -EFAULT;
+	if (sflags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
+		err = snd_pcm_hwsync(substream);
+		if (err < 0)
+			return err;
+	}
+	status = runtime->status;
+	control = runtime->control;
+	boundary = recalculate_boundary(runtime);
+	if (!boundary)
+		boundary = 0x7fffffff;
+	snd_pcm_stream_lock_irq(substream);
+	/* FIXME: we should consider the boundary for the sync from app */
+	if (!(sflags & SNDRV_PCM_SYNC_PTR_APPL))
+		control->appl_ptr = scontrol.appl_ptr;
+	else
+		scontrol.appl_ptr = control->appl_ptr % boundary;
+	if (!(sflags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
+		control->avail_min = scontrol.avail_min;
+	else
+		scontrol.avail_min = control->avail_min;
+	sstatus.state = status->state;
+	sstatus.hw_ptr = status->hw_ptr % boundary;
+	sstatus.tstamp = status->tstamp;
+	sstatus.suspended_state = status->suspended_state;
+	sstatus.audio_tstamp = status->audio_tstamp;
+	snd_pcm_stream_unlock_irq(substream);
+	if (put_user(sstatus.state, &src->s.status.state) ||
+	    put_user(sstatus.hw_ptr, &src->s.status.hw_ptr) ||
+	    put_timespec(&sstatus.tstamp, &src->s.status.tstamp) ||
+	    put_user(sstatus.suspended_state, &src->s.status.suspended_state) ||
+	    put_timespec(&sstatus.audio_tstamp, &src->s.status.audio_tstamp) ||
+	    put_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
+	    put_user(scontrol.avail_min, &src->c.control.avail_min))
+		return -EFAULT;
+
+	return 0;
+}
+#endif /* CONFIG_X86_X32 */
 
 /*
  */
@@ -487,7 +647,12 @@ enum {
 	SNDRV_PCM_IOCTL_WRITEN_FRAMES32 = _IOW('A', 0x52, struct snd_xfern32),
 	SNDRV_PCM_IOCTL_READN_FRAMES32 = _IOR('A', 0x53, struct snd_xfern32),
 	SNDRV_PCM_IOCTL_SYNC_PTR32 = _IOWR('A', 0x23, struct snd_pcm_sync_ptr32),
-
+#ifdef CONFIG_X86_X32
+	SNDRV_PCM_IOCTL_CHANNEL_INFO_X32 = _IOR('A', 0x32, struct snd_pcm_channel_info),
+	SNDRV_PCM_IOCTL_STATUS_X32 = _IOR('A', 0x20, struct snd_pcm_status_x32),
+	SNDRV_PCM_IOCTL_STATUS_EXT_X32 = _IOWR('A', 0x24, struct snd_pcm_status_x32),
+	SNDRV_PCM_IOCTL_SYNC_PTR_X32 = _IOWR('A', 0x23, struct snd_pcm_sync_ptr_x32),
+#endif /* CONFIG_X86_X32 */
 };
 
 static long snd_pcm_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
@@ -559,6 +724,16 @@ static long snd_pcm_ioctl_compat(struct file *file, unsigned int cmd, unsigned l
 		return snd_pcm_ioctl_rewind_compat(substream, argp);
 	case SNDRV_PCM_IOCTL_FORWARD32:
 		return snd_pcm_ioctl_forward_compat(substream, argp);
+#ifdef CONFIG_X86_X32
+	case SNDRV_PCM_IOCTL_STATUS_X32:
+		return snd_pcm_status_user_x32(substream, argp, false);
+	case SNDRV_PCM_IOCTL_STATUS_EXT_X32:
+		return snd_pcm_status_user_x32(substream, argp, true);
+	case SNDRV_PCM_IOCTL_SYNC_PTR_X32:
+		return snd_pcm_ioctl_sync_ptr_x32(substream, argp);
+	case SNDRV_PCM_IOCTL_CHANNEL_INFO_X32:
+		return snd_pcm_ioctl_channel_info_x32(substream, argp);
+#endif /* CONFIG_X86_X32 */
 	}
 
 	return -ENOIOCTLCMD;
-- 
2.7.2



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