Fix segfault caused by buffer over-read. Check that index is not
bigger than MAX_INDEX.
This bug was found by fuzzing with AFL.
Program received signal SIGSEGV, Segmentation fault.
0x0000000000420bb8 in print_packet (tv=<optimized out>, cred=<optimized out>, ident=<optimized out>, index=<optimized out>, channel=<optimized out>, color=<optimized out>,
label=<optimized out>, text=<optimized out>, extra=<optimized out>) at monitor/packet.c:317
warning: Source file is more recent than executable.
317 index_list[index].frame != last_frame) {
(gdb) bt
#0 0x0000000000420bb8 in print_packet (tv=<optimized out>, cred=<optimized out>, ident=<optimized out>, index=<optimized out>, channel=<optimized out>, color=<optimized out>,
label=<optimized out>, text=<optimized out>, extra=<optimized out>) at monitor/packet.c:317
#1 0x000000000041a8c3 in packet_new_index (tv=<optimized out>, index=<optimized out>, name=0x7fffffffda68 "rsion 4.18.0-matias-patch2 (x86_64)", label=<optimized out>,
type=<optimized out>, bus=<optimized out>) at monitor/packet.c:9818
#2 packet_monitor (tv=0x7fffffffda50, cred=<optimized out>, index=<optimized out>, opcode=<optimized out>, data=0x7fffffffda60, size=<optimized out>) at monitor/packet.c:3881
#3 0x000000000040e177 in control_reader (path=<optimized out>, pager=true) at monitor/control.c:1462
#4 0x0000000000403b00 in main (argc=<optimized out>, argv=<optimized out>) at monitor/main.c:243
---
monitor/packet.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/monitor/packet.c b/monitor/packet.c
index cecb295bd..64faceca1 100644
--- a/monitor/packet.c
+++ b/monitor/packet.c
@@ -313,7 +313,7 @@ static void print_packet(struct timeval *tv, struct ucred *cred, char ident,
ts_pos += n;
ts_len += n;
}
- } else if (index != HCI_DEV_NONE &&
+ } else if (index != HCI_DEV_NONE && index < MAX_INDEX &&
index_list[index].frame != last_frame) {
if (use_color()) {
n = sprintf(ts_str + ts_pos, "%s", COLOR_FRAME_LABEL);
--
2.17.1
