Fix heap buffer overflow in sbrDecoder_AssignQmfChannels2SbrChannels().

In the bug the SBR decoder has already set up 9 channels and tries to
allocate one more channel. The assignment of the QMF channels to SBR
channels fails since the QMF domain manages only 8+1 channels instead
of 10 channels as reqeusted by SBR.
Here we have added a check in sbrDecoder_InitElement() which will
return with a parse error in case additional SBR channels would exceed
the maximum number of SBR channels. This solves the potential heap
buffer overflow.

Bug: 158762825
Test: atest DecoderTestAacDrc DecoderTestAacFormat DecoderTestXheAac
Merged-In: I0150ac6d5a47ffce883010f531928656eebc619e
Change-Id: I8569a15214707ab622e986b34b4b917251495662
This commit is contained in:
Fraunhofer IIS FDK 2020-07-06 15:12:34 -07:00 committed by Jean-Michel Trivi
parent b81f869de3
commit c516539a20
1 changed files with 5 additions and 5 deletions

View File

@ -619,10 +619,6 @@ SBR_ERROR sbrDecoder_InitElement(
self->numSbrChannels -= self->pSbrElement[elementIndex]->nChannels;
}
/* Save element ID for sanity checks and to have a fallback for concealment.
*/
self->pSbrElement[elementIndex]->elementID = elementID;
/* Determine amount of channels for this element */
switch (elementID) {
case ID_NONE:
@ -655,12 +651,16 @@ SBR_ERROR sbrDecoder_InitElement(
}
/* Sanity check to avoid memory leaks */
if (elChannels < self->pSbrElement[elementIndex]->nChannels) {
if (elChannels < self->pSbrElement[elementIndex]->nChannels ||
(self->numSbrChannels + elChannels) > (8) + (1)) {
self->numSbrChannels += self->pSbrElement[elementIndex]->nChannels;
sbrError = SBRDEC_PARSE_ERROR;
goto bail;
}
/* Save element ID for sanity checks and to have a fallback for concealment.
*/
self->pSbrElement[elementIndex]->elementID = elementID;
self->pSbrElement[elementIndex]->nChannels = elChannels;
for (ch = 0; ch < elChannels; ch++) {