alsa-project/alsa-utils issue #282 was opened from geoffreybennett:
While trying to figure out how TLVs work, I found that if the length field is not a multiple of 4 then amixer and alsactl keep reading past the end of the buffer until they segfault, because size is unsigned. One example here: ``` diff --git a/amixer/amixer.c b/amixer/amixer.c index 8b8000b..03cc9cb 100644 --- a/amixer/amixer.c +++ b/amixer/amixer.c @@ -587,7 +587,7 @@ static void decode_tlv(unsigned int spaces, unsigned int *tlv, unsigned int tlv_ #endif default: printf("unk-%u-", type); - while (size > 0) { + while (size >= sizeof(unsigned int)) { printf("0x%08x,", tlv[idx++]); size -= sizeof(unsigned int); } ```
Issue URL : https://github.com/alsa-project/alsa-utils/issues/282 Repository URL: https://github.com/alsa-project/alsa-utils