IPv6 support issue in flb_hs_create

[ryanlyy]

In below code, tmp length is 32. but if ipv6 address is like: 1234:5678:1234:5678:1234:5678:1234:5678. and if port is 33333. then the total length of listen address is: 32 + 7 + 5 = 44. But the buff tmp is only 32 bytes. so there will be memory issue.

/* Create ROOT endpoints */
struct flb_hs *flb_hs_create(const char *listen, const char *tcp_port,
struct flb_config *config)
{
int vid;
char tmp[32];

/* Compose listen address */
snprintf(tmp, sizeof(tmp) -1, "%s:%s", listen, tcp_port);

[niedbalski]

I confirm this issue. To my understanding v6 addresses can be up to 39 characters long (1234:5678:1234:5678:1234:5678:1234:5678 is a valid example), and ports can be up to 5 characters long (65535). Also, we need to account for the colon (:) between the address and port. Thus, the maximum length would be: 39 (IPv6 address) + 1 (colon) + 5 (port) = 45.

For context should refer to this RFC 4291 -- My understanding is that this affects http server (

fluent-bit/src/flb_engine.c

Line 873 in dd53a39

#ifdef FLB_HAVE_HTTP_SERVER

)