staging: speakup: avoid out-of-range access in synth_add()
Samuel Thibault [Mon, 7 Jan 2013 21:03:51 +0000 (22:03 +0100)]
commit 6102c48bd421074a33e102f2ebda3724e8d275f9 upstream.

Check that array index is in-bounds before accessing the synths[] array.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Nickolai Zeldovich <nickolai@csail.mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/speakup/synth.c

index 217fd4a..5710fc5 100644 (file)
@@ -423,7 +423,7 @@ int synth_add(struct spk_synth *in_synth)
        int i;
        int status = 0;
        mutex_lock(&spk_mutex);
-       for (i = 0; synths[i] != NULL && i < MAXSYNTHS; i++)
+       for (i = 0; i < MAXSYNTHS && synths[i] != NULL; i++)
                /* synth_remove() is responsible for rotating the array down */
                if (in_synth == synths[i]) {
                        mutex_unlock(&spk_mutex);