dsp: q6asm: check for buffer size before read

Check for debugfs ops buf size passed before reading
to avoid reading out of bounds.

Change-Id: Idd5e755ac16448af5751e2f3381097f234e74a74
Signed-off-by: Karthikeyan Mani <[email protected]>

dsp/q6asm.c

@@ -284,6 +284,11 @@ static ssize_t audio_output_latency_dbgfs_read(struct file *file,
 		pr_err("%s: out_buffer is null\n", __func__);
 		return 0;
 	}
+	if (count < OUT_BUFFER_SIZE) {
+		pr_err("%s: read size %d exceeds buf size %zd\n", __func__,
+						OUT_BUFFER_SIZE, count);
+		return 0;
+	}
 	snprintf(out_buffer, OUT_BUFFER_SIZE, "%ld,%ld,%ld,%ld,%ld,%ld,",
 		out_cold_tv.tv_sec, out_cold_tv.tv_usec, out_warm_tv.tv_sec,
 		out_warm_tv.tv_usec, out_cont_tv.tv_sec, out_cont_tv.tv_usec);
@@ -336,6 +341,11 @@ static ssize_t audio_input_latency_dbgfs_read(struct file *file,
 		pr_err("%s: in_buffer is null\n", __func__);
 		return 0;
 	}
+	if (count < IN_BUFFER_SIZE) {
+		pr_err("%s: read size %d exceeds buf size %zd\n", __func__,
+						IN_BUFFER_SIZE, count);
+		return 0;
+	}
 	snprintf(in_buffer, IN_BUFFER_SIZE, "%ld,%ld,",
 				in_cont_tv.tv_sec, in_cont_tv.tv_usec);
 	return  simple_read_from_buffer(buf, IN_BUFFER_SIZE, ppos,