[BUG] scsi: iscsi: possible null-pointer dereference in iscsit_tpg_add_network_portal()

[Tuo Li]

Hello,

Our static analysis tool finds a possible null-pointer dereference in 
the iscsi driver in Linux 5.14.0-rc3:

The variable tpg->tpg_tiqn is checked in:
496:    if (tpg->tpg_tiqn)

This indicates that it can be NULL. If so, a null-pointer dereference 
will occur:
508:    pr_debug("CORE[%s] - Added Network Portal: %pISpc,%hu on %s\n", 
tpg->tpg_tiqn->tiqn, ...)

I am not quite sure whether this possible null-pointer dereference is 
real and how to fix it if it is real.
Any feedback would be appreciated, thanks!

Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>

Best wishes,
Tuo Li