ALSA: bebob: Uninitialized id returned by saffirepro_both_clk_src_get

snd_bebob_stream_check_internal_clock() may get an id from
saffirepro_both_clk_src_get (via clk_src->get()) that was uninitialized.

a) make logic in saffirepro_both_clk_src_get explicit
b) test if id used in snd_bebob_stream_check_internal_clock matches array size

[fixed missing signed prefix to *_maps[] by tiwai]

Signed-off-by: Christian Vogel <vogelchr@vogel.cx>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/firewire/bebob/bebob_focusrite.c b/sound/firewire/bebob/bebob_focusrite.c
index 45a0eed6d5b17413eaa002e8eb4eafeef2d67088..3b052ed0fbf58d284d55b562ac46ec1ee65cc763 100644 (file)
--- a/sound/firewire/bebob/bebob_focusrite.c
+++ b/sound/firewire/bebob/bebob_focusrite.c
@@ -27,12 +27,14 @@
 #define SAFFIRE_CLOCK_SOURCE_INTERNAL          0
 #define SAFFIRE_CLOCK_SOURCE_SPDIF             1
 
-/* '1' is absent, why... */
+/* clock sources as returned from register of Saffire Pro 10 and 26 */
 #define SAFFIREPRO_CLOCK_SOURCE_INTERNAL       0
+#define SAFFIREPRO_CLOCK_SOURCE_SKIP           1 /* never used on hardware */
 #define SAFFIREPRO_CLOCK_SOURCE_SPDIF          2
-#define SAFFIREPRO_CLOCK_SOURCE_ADAT1          3
-#define SAFFIREPRO_CLOCK_SOURCE_ADAT2          4
+#define SAFFIREPRO_CLOCK_SOURCE_ADAT1          3 /* not used on s.pro. 10 */
+#define SAFFIREPRO_CLOCK_SOURCE_ADAT2          4 /* not used on s.pro. 10 */
 #define SAFFIREPRO_CLOCK_SOURCE_WORDCLOCK      5
+#define SAFFIREPRO_CLOCK_SOURCE_COUNT          6
 
 /* S/PDIF, ADAT1, ADAT2 is enabled or not. three quadlets */
 #define SAFFIREPRO_ENABLE_DIG_IFACES           0x01a4
@@ -101,13 +103,34 @@ saffire_write_quad(struct snd_bebob *bebob, u64 offset, u32 value)
                                  &data, sizeof(__be32), 0);
 }
 
+static char *const saffirepro_10_clk_src_labels[] = {
+       SND_BEBOB_CLOCK_INTERNAL, "S/PDIF", "Word Clock"
+};
 static char *const saffirepro_26_clk_src_labels[] = {
        SND_BEBOB_CLOCK_INTERNAL, "S/PDIF", "ADAT1", "ADAT2", "Word Clock"
 };
-
-static char *const saffirepro_10_clk_src_labels[] = {
-       SND_BEBOB_CLOCK_INTERNAL, "S/PDIF", "Word Clock"
+/* Value maps between registers and labels for SaffirePro 10/26. */
+static const signed char saffirepro_clk_maps[][SAFFIREPRO_CLOCK_SOURCE_COUNT] = {
+       /* SaffirePro 10 */
+       [0] = {
+               [SAFFIREPRO_CLOCK_SOURCE_INTERNAL]  =  0,
+               [SAFFIREPRO_CLOCK_SOURCE_SKIP]      = -1, /* not supported */
+               [SAFFIREPRO_CLOCK_SOURCE_SPDIF]     =  1,
+               [SAFFIREPRO_CLOCK_SOURCE_ADAT1]     = -1, /* not supported */
+               [SAFFIREPRO_CLOCK_SOURCE_ADAT2]     = -1, /* not supported */
+               [SAFFIREPRO_CLOCK_SOURCE_WORDCLOCK] =  2,
+       },
+       /* SaffirePro 26 */
+       [1] = {
+               [SAFFIREPRO_CLOCK_SOURCE_INTERNAL]  =  0,
+               [SAFFIREPRO_CLOCK_SOURCE_SKIP]      = -1, /* not supported */
+               [SAFFIREPRO_CLOCK_SOURCE_SPDIF]     =  1,
+               [SAFFIREPRO_CLOCK_SOURCE_ADAT1]     =  2,
+               [SAFFIREPRO_CLOCK_SOURCE_ADAT2]     =  3,
+               [SAFFIREPRO_CLOCK_SOURCE_WORDCLOCK] =  4,
+       }
 };
+
 static int
 saffirepro_both_clk_freq_get(struct snd_bebob *bebob, unsigned int *rate)
 {
@@ -138,24 +161,35 @@ saffirepro_both_clk_freq_set(struct snd_bebob *bebob, unsigned int rate)
 
        return saffire_write_quad(bebob, SAFFIREPRO_RATE_NOREBOOT, id);
 }
+
+/*
+ * query hardware for current clock source, return our internally
+ * used clock index in *id, depending on hardware.
+ */
 static int
 saffirepro_both_clk_src_get(struct snd_bebob *bebob, unsigned int *id)
 {
        int err;
-       u32 value;
+       u32 value;       /* clock source read from hw register */
+       const signed char *map;
 
        err = saffire_read_quad(bebob, SAFFIREPRO_OFFSET_CLOCK_SOURCE, &value);
        if (err < 0)
                goto end;
 
-       if (bebob->spec->clock->labels == saffirepro_10_clk_src_labels) {
-               if (value == SAFFIREPRO_CLOCK_SOURCE_WORDCLOCK)
-                       *id = 2;
-               else if (value == SAFFIREPRO_CLOCK_SOURCE_SPDIF)
-                       *id = 1;
-       } else if (value > 1) {
-               *id = value - 1;
+       /* depending on hardware, use a different mapping */
+       if (bebob->spec->clock->labels == saffirepro_10_clk_src_labels)
+               map = saffirepro_clk_maps[0];
+       else
+               map = saffirepro_clk_maps[1];
+
+       /* In a case that this driver cannot handle the value of register. */
+       if (value >= SAFFIREPRO_CLOCK_SOURCE_COUNT || map[value] < 0) {
+               err = -EIO;
+               goto end;
        }
+
+       *id = (unsigned int)map[value];
 end:
        return err;
 }

diff --git a/sound/firewire/bebob/bebob_stream.c b/sound/firewire/bebob/bebob_stream.c
index ef4d0c9f65781a2e2684a143264a8b3aad12d8be..1aab0a32870c84d20a0c5b87f46d625299b34fd4 100644 (file)
--- a/sound/firewire/bebob/bebob_stream.c
+++ b/sound/firewire/bebob/bebob_stream.c
@@ -129,12 +129,24 @@ snd_bebob_stream_check_internal_clock(struct snd_bebob *bebob, bool *internal)
        /* 1.The device has its own operation to switch source of clock */
        if (clk_spec) {
                err = clk_spec->get(bebob, &id);
-               if (err < 0)
+               if (err < 0) {
                        dev_err(&bebob->unit->device,
                                "fail to get clock source: %d\n", err);
-               else if (strncmp(clk_spec->labels[id], SND_BEBOB_CLOCK_INTERNAL,
-                                strlen(SND_BEBOB_CLOCK_INTERNAL)) == 0)
+                       goto end;
+               }
+
+               if (id >= clk_spec->num) {
+                       dev_err(&bebob->unit->device,
+                               "clock source %d out of range 0..%d\n",
+                               id, clk_spec->num - 1);
+                       err = -EIO;
+                       goto end;
+               }
+
+               if (strncmp(clk_spec->labels[id], SND_BEBOB_CLOCK_INTERNAL,
+                           strlen(SND_BEBOB_CLOCK_INTERNAL)) == 0)
                        *internal = true;
+
                goto end;
        }