diff options
| -rw-r--r-- | media/libstagefright/OggExtractor.cpp | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/media/libstagefright/OggExtractor.cpp b/media/libstagefright/OggExtractor.cpp index 976763c..866c604 100644 --- a/media/libstagefright/OggExtractor.cpp +++ b/media/libstagefright/OggExtractor.cpp @@ -894,11 +894,14 @@ static uint8_t *DecodeBase64(const char *s, size_t size, size_t *outSize) { } } - size_t outLen = 3 * size / 4 - padding; - - *outSize = outLen; + // We divide first to avoid overflow. It's OK to do this because we + // already made sure that size % 4 == 0. + size_t outLen = (size / 4) * 3 - padding; void *buffer = malloc(outLen); + if (buffer == NULL) { + return NULL; + } uint8_t *out = (uint8_t *)buffer; size_t j = 0; @@ -917,10 +920,10 @@ static uint8_t *DecodeBase64(const char *s, size_t size, size_t *outSize) { } else if (c == '/') { value = 63; } else if (c != '=') { - return NULL; + break; } else { if (i < n - padding) { - return NULL; + break; } value = 0; @@ -938,6 +941,13 @@ static uint8_t *DecodeBase64(const char *s, size_t size, size_t *outSize) { } } + // Check if we exited the loop early. + if (j < outLen) { + free(buffer); + return NULL; + } + + *outSize = outLen; return (uint8_t *)buffer; } |