From 50aa5be38870319395ce2ef6f91543e6475e4b97 Mon Sep 17 00:00:00 2001 From: Fraunhofer IIS FDK Date: Mon, 6 Jul 2020 12:28:12 -0700 Subject: [PATCH] [DO NOT MERGE] 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 DecoderTestXheAac Change-Id: I741f49ab3b675fa3d3217ee72e1db66b0114f7ee --- libSBRdec/src/sbrdecoder.cpp | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/libSBRdec/src/sbrdecoder.cpp b/libSBRdec/src/sbrdecoder.cpp index f9ded54..2452f8e 100644 --- a/libSBRdec/src/sbrdecoder.cpp +++ b/libSBRdec/src/sbrdecoder.cpp @@ -510,9 +510,6 @@ 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: @@ -540,6 +537,16 @@ SBR_ERROR sbrDecoder_InitElement ( } } + /* Sanity check to avoid memory leaks */ + 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