Fix multiple segfaults caused by buffer over-read in packet_hci_command, packet_hci_event and packet_hci_acldata. Fix is to check that index is not bigger than MAX_INDEX before accessing index_list. Crashes were found by fuzzing btmon with AFL. --- monitor/packet.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/monitor/packet.c b/monitor/packet.c index 8f7464b1f..abdc18aa2 100644 --- a/monitor/packet.c +++ b/monitor/packet.c @@ -9949,13 +9949,17 @@ void packet_hci_command(struct timeval *tv, struct ucred *cred, uint16_t index, char extra_str[25], vendor_str[150]; int i; + if (index > MAX_INDEX) { + print_field("Invalid index (%d).", index); + return; + } + index_list[index].frame++; - if (size < HCI_COMMAND_HDR_SIZE) { + if (size < HCI_COMMAND_HDR_SIZE || size > BTSNOOP_MAX_PACKET_SIZE) { sprintf(extra_str, "(len %d)", size); print_packet(tv, cred, '*', index, NULL, COLOR_ERROR, "Malformed HCI Command packet", NULL, extra_str); - packet_hexdump(data, size); return; } @@ -10052,6 +10056,12 @@ void packet_hci_event(struct timeval *tv, struct ucred *cred, uint16_t index, char extra_str[25]; int i; + if (index > MAX_INDEX) { + print_field("Invalid index (%d).", index); + return; + } + + index_list[index].frame++; if (size < HCI_EVENT_HDR_SIZE) { @@ -10126,6 +10136,11 @@ void packet_hci_acldata(struct timeval *tv, struct ucred *cred, uint16_t index, uint8_t flags = acl_flags(handle); char handle_str[16], extra_str[32]; + if (index > MAX_INDEX) { + print_field("Invalid index (%d).", index); + return; + } + index_list[index].frame++; if (size < HCI_ACL_HDR_SIZE) { -- 2.17.1