shithub: sox

Info  •  Files  •  Log  •  Branches

rate: don't hang if more than 2^31 output samples

The rate effect used to hang in an endless loop (until memory
exhaustion) when the number of output samples exceeded 2^31 (on
"normal" platforms; depending on size and signedness of size_t
and int), as in this example:
  sox -V -S -n -n trim 0 3:10:00 rate 192000
Use 64-bit numbers for counting samples, and don't subtract unsigned
numbers without checking.

Reported and analyzed by MrMod in tracker item 3592482. This same
problem is already fixed in the post-14.4.1 branch (commit c20cfab;
in conjunction with commit eb20581 for the 64-bit numbers).

--- a/src/rate.c

+++ b/src/rate.c

@@ -223,7 +223,7 @@

 typedef struct {

   double     factor;

-  size_t     samples_in, samples_out;

+  uint64_t   samples_in, samples_out;

   int        level, input_stage_num, output_stage_num;

   sox_bool   upsample;

   stage_t    * stages;

@@ -393,11 +393,12 @@

 static void rate_flush(rate_t * p)

 {

   fifo_t * fifo = &p->stages[p->output_stage_num].fifo;

-  size_t samples_out = p->samples_in / p->factor + .5;

-  size_t remaining = samples_out - p->samples_out;

+  uint64_t samples_out = p->samples_in / p->factor + .5;

+  size_t remaining = samples_out > p->samples_out ?

+      (size_t)(samples_out - p->samples_out) : 0;

   sample_t * buff = calloc(1024, sizeof(*buff));

-  if ((int)remaining > 0) {

+  if (remaining > 0) {

     while ((size_t)fifo_occupancy(fifo) < remaining) {

       rate_input(p, buff, (size_t) 1024);

       rate_process(p);