Hi Steve,
you should made this generic (not ipv4/ipv6 specific) and use something like this:
TP_PROTO(const char *hostname, __u64 conn_id, const struct sockaddr_storage *dst_addr)
TP_STRUCT__entry(
__string(hostname, hostname)
__field(__u64, conn_id)
__field(struct sockaddr_storage, dst_addr)
TP_fast_assign(
__entry->conn_id = conn_id;
__entry->dst_addr = *dst_addr;
__assign_str(hostname, hostname);
),
With that you should be able to use this:
TP_printk("conn_id=0x%llx server=%s addr=%pISpsfc",
__entry->conn_id,
__get_str(hostname),
&__entry->dst_addr)
I hope that helps.
metze
Am 04.11.21 um 07:09 schrieb Steve French:
> It wasn't obvious to me the best way to pass in a pointer to the ipv4
> (and ipv6 address) to a dynamic trace point (unless I create a temp
> string first in generic_ip_connect and do the conversion (via "%pI4"
> and "%pI6" with sprintf) e.g.
>
> sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
>
> The approach I tried passing in the pointer to sin_addr (the
> ipv4_address) caused an oops on loading it the first time and the
> warning:
>
> [14928.818532] event smb3_ipv4_connect has unsafe dereference of argument 3
> [14928.818534] print_fmt: "conn_id=0x%llx server=%s addr=%pI4:%d",
> REC->conn_id, __get_str(hostname), REC->ipaddr, REC->port
>
>
> What I tried was the following (also see attached diff) to print the
> ipv4 address that we were trying to connect to
>
> DECLARE_EVENT_CLASS(smb3_connect_class,
> TP_PROTO(char *hostname,
> __u64 conn_id,
> __u16 port,
> struct in_addr *ipaddr),
> TP_ARGS(hostname, conn_id, port, ipaddr),
> TP_STRUCT__entry(
> __string(hostname, hostname)
> __field(__u64, conn_id)
> __field(__u16, port)
> __field(const void *, ipaddr)
> ),
> TP_fast_assign(
> __entry->port = port;
> __entry->conn_id = conn_id;
> __entry->ipaddr = ipaddr;
> __assign_str(hostname, hostname);
> ),
> TP_printk("conn_id=0x%llx server=%s addr=%pI4:%d",
> __entry->conn_id,
> __get_str(hostname),
> __entry->ipaddr,
> __entry->port)
> )
>
> #define DEFINE_SMB3_CONNECT_EVENT(name) \
> DEFINE_EVENT(smb3_connect_class, smb3_##name, \
> TP_PROTO(char *hostname, \
> __u64 conn_id, \
> __u16 port, \
> struct in_addr *ipaddr), \
> TP_ARGS(hostname, conn_id, port, ipaddr))
>
> DEFINE_SMB3_CONNECT_EVENT(ipv4_connect);
>
> Any ideas how to pass in the ipv4 address - or is it better to convert
> it to a string before we call the trace point (which seems wasteful to
> me but there must be examples of how to pass in structs to printks in
> trace in Linux)
>
