Wrong pointer conversion in get_data_source_tvb_by_name()

Summary

There is a wrong pointer conversion in get_data_source_tvb_by_name(). data_source pointer should be retrived from source->data rather than source itself. See below

// in epan/packet.c
tvbuff_t *
get_data_source_tvb_by_name(packet_info *pinfo, const char *name)
{
	GSList *source;
	for (source = pinfo->data_src; source; source = source->next) {
		struct data_source *this_source = (struct data_source *)source; // should be (struct data_source *)source->data
		if (this_source->name && strcmp(this_source->name, name) == 0) {
			return this_source->tvb;
		}
	}
	return NULL;
}

Steps to reproduce

I write a dissector plugin and call get_data_source_tvb_by_name(pinfo, "Reassembled TCP"); in dissect function, and find it can't get correct tvb. After I change code like above this fuction return correct tvb.

Build information

• OS: Windows 11
• IDE: Visual Studio 2019
• Wireshark: 4.0.0 (newer version has this issue too)