[PATCH 4.4 48/74] ALSA: rawmidi: Fix ioctls X32 ABI

Greg Kroah-Hartman
2016-03-08T00:11:47Z

From: Takashi Iwai <tiwai@suse.de>

commit 2251fbbc1539f05b0b206b37a602d5776be37252 upstream.

Like the previous fixes for ctl and PCM, we need a fix for
incompatible X32 ABI regarding the rawmidi: namely, struct
snd_rawmidi_status has the timespec, and the size and the alignment on
X32 differ from IA32.

This patch fixes the incompatible ioctl for X32.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/core/rawmidi_compat.c | 53 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)

--- a/sound/core/rawmidi_compat.c
+++ b/sound/core/rawmidi_compat.c
@@ -94,9 +94,58 @@ static int snd_rawmidi_ioctl_status_comp
return 0;
}

+#ifdef CONFIG_X86_X32
+/* X32 ABI has 64bit timespec and 64bit alignment */
+struct snd_rawmidi_status_x32 {
+ s32 stream;
+ u32 rsvd; /* alignment */
+ struct timespec tstamp;
+ u32 avail;
+ u32 xruns;
+ unsigned char reserved[16];
+} __attribute__((packed));
+
+#define put_timespec(src, dst) copy_to_user(dst, src, sizeof(*dst))
+
+static int snd_rawmidi_ioctl_status_x32(struct snd_rawmidi_file *rfile,
+ struct snd_rawmidi_status_x32 __user *src)
+{
+ int err;
+ struct snd_rawmidi_status status;
+
+ if (rfile->output == NULL)
+ return -EINVAL;
+ if (get_user(status.stream, &src->stream))
+ return -EFAULT;
+
+ switch (status.stream) {
+ case SNDRV_RAWMIDI_STREAM_OUTPUT:
+ err = snd_rawmidi_output_status(rfile->output, &status);
+ break;
+ case SNDRV_RAWMIDI_STREAM_INPUT:
+ err = snd_rawmidi_input_status(rfile->input, &status);
+ break;
+ default:
+ return -EINVAL;
+ }
+ if (err < 0)
+ return err;
+
+ if (put_timespec(&status.tstamp, &src->tstamp) ||
+ put_user(status.avail, &src->avail) ||
+ put_user(status.xruns, &src->xruns))
+ return -EFAULT;
+
+ return 0;
+}
+#endif /* CONFIG_X86_X32 */
+
enum {
SNDRV_RAWMIDI_IOCTL_PARAMS32 = _IOWR('W', 0x10, struct snd_rawmidi_params32),
SNDRV_RAWMIDI_IOCTL_STATUS32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
+#ifdef CONFIG_X86_X32
+ SNDRV_RAWMIDI_IOCTL_STATUS_X32 = _IOWR('W', 0x20, struct snd_rawmidi_status_x32),
+#endif /* CONFIG_X86_X32 */
};

static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
@@ -115,6 +164,10 @@ static long snd_rawmidi_ioctl_compat(str
return snd_rawmidi_ioctl_params_compat(rfile, argp);
case SNDRV_RAWMIDI_IOCTL_STATUS32:
return snd_rawmidi_ioctl_status_compat(rfile, argp);
+#ifdef CONFIG_X86_X32
+ case SNDRV_RAWMIDI_IOCTL_STATUS_X32:
+ return snd_rawmidi_ioctl_status_x32(rfile, argp);
+#endif /* CONFIG_X86_X32 */
}
return -ENOIOCTLCMD;
}