From 1206eee71cd475882f0af9c4ec7990ae4822ddfe Mon Sep 17 00:00:00 2001 From: Matias Karhumaa Date: Tue, 16 Oct 2018 23:23:12 +0300 Subject: [PATCH] btmon: fix segfault caused by integer undeflow Fix segfault caused by integer underflow. Fix is to check that rsp->num_codecs + 3 is not bigger than size before subtracting. Crash was found by fuzzing btmon with AFL. --- monitor/packet.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/monitor/packet.c b/monitor/packet.c index 914eaedbc..bb2f5a8b7 100644 --- a/monitor/packet.c +++ b/monitor/packet.c @@ -5830,6 +5830,11 @@ static void read_local_codecs_rsp(const void *data, uint8_t size) const struct bt_hci_rsp_read_local_codecs *rsp = data; uint8_t i, num_vnd_codecs; + if (rsp->num_codecs + 3 > size) { + print_field("Invalid number of codecs."); + return; + } + print_status(rsp->status); print_field("Number of supported codecs: %d", rsp->num_codecs); -- 2.47.3