ALSA: Avoid using timespec for struct snd_rawmidi_status

The struct snd_rawmidi_status will use 'timespec' type variables to record
timestamp, which is not year 2038 safe on 32bits system.

Thus we introduced 'struct snd_rawmidi_status32' and 'struct snd_rawmidi_status64'
to handle 32bit time_t and 64bit time_t in native mode, which replace
timespec with s64 type.

In compat mode, we renamed or introduced new structures to handle 32bit/64bit
time_t in compatible mode. The 'struct snd_rawmidi_status32' and
snd_rawmidi_ioctl_status32() are used to handle 32bit time_t in compat mode.
'struct compat_snd_rawmidi_status64' is used to handle 64bit time_t.

When glibc changes time_t to 64-bit, any recompiled program will issue ioctl
commands that the kernel does not understand without this patch.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 22 insertions, 65 deletions

diff --git a/sound/core/rawmidi_compat.c b/sound/core/rawmidi_compat.c
index 66eee61674b6..7397130976d0 100644
--- a/sound/core/rawmidi_compat.c
+++ b/sound/core/rawmidi_compat.c
@@ -41,19 +41,22 @@ static int snd_rawmidi_ioctl_params_compat(struct snd_rawmidi_file *rfile,
 	return -EINVAL;
 }
 
-struct snd_rawmidi_status32 {
+struct compat_snd_rawmidi_status64 {
 	s32 stream;
-	struct compat_timespec tstamp;
+	u8 rsvd[4]; /* alignment */
+	s64 tstamp_sec;
+	s64 tstamp_nsec;
 	u32 avail;
 	u32 xruns;
 	unsigned char reserved[16];
 } __attribute__((packed));
 
-static int snd_rawmidi_ioctl_status_compat(struct snd_rawmidi_file *rfile,
-					   struct snd_rawmidi_status32 __user *src)
+static int snd_rawmidi_ioctl_status_compat64(struct snd_rawmidi_file *rfile,
+					     struct compat_snd_rawmidi_status64 __user *src)
 {
 	int err;
-	struct snd_rawmidi_status status;
+	struct snd_rawmidi_status64 status;
+	struct compat_snd_rawmidi_status64 compat_status;
 
 	if (get_user(status.stream, &src->stream))
 		return -EFAULT;
@@ -75,68 +78,24 @@ static int snd_rawmidi_ioctl_status_compat(struct snd_rawmidi_file *rfile,
 	if (err < 0)
 		return err;
 
-	if (compat_put_timespec(&status.tstamp, &src->tstamp) ||
-	    put_user(status.avail, &src->avail) ||
-	    put_user(status.xruns, &src->xruns))
-		return -EFAULT;
-
-	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 (get_user(status.stream, &src->stream))
-		return -EFAULT;
-
-	switch (status.stream) {
-	case SNDRV_RAWMIDI_STREAM_OUTPUT:
-		if (!rfile->output)
-			return -EINVAL;
-		err = snd_rawmidi_output_status(rfile->output, &status);
-		break;
-	case SNDRV_RAWMIDI_STREAM_INPUT:
-		if (!rfile->input)
-			return -EINVAL;
-		err = snd_rawmidi_input_status(rfile->input, &status);
-		break;
-	default:
-		return -EINVAL;
-	}
-	if (err < 0)
-		return err;
+	compat_status = (struct compat_snd_rawmidi_status64) {
+		.stream = status.stream,
+		.tstamp_sec = status.tstamp_sec,
+		.tstamp_nsec = status.tstamp_nsec,
+		.avail = status.avail,
+		.xruns = status.xruns,
+	};
 
-	if (put_timespec(&status.tstamp, &src->tstamp) ||
-	    put_user(status.avail, &src->avail) ||
-	    put_user(status.xruns, &src->xruns))
+	if (copy_to_user(src, &compat_status, sizeof(*src)))
 		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 */
+	SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
+	SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64 = _IOWR('W', 0x20, struct compat_snd_rawmidi_status64),
 };
 
 static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
@@ -153,12 +112,10 @@ static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsign
 		return snd_rawmidi_ioctl(file, cmd, (unsigned long)argp);
 	case SNDRV_RAWMIDI_IOCTL_PARAMS32:
 		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 */
+	case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32:
+		return snd_rawmidi_ioctl_status32(rfile, argp);
+	case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64:
+		return snd_rawmidi_ioctl_status_compat64(rfile, argp);
 	}
 	return -ENOIOCTLCMD;
 }