tree 9f2f1047638f6be922ec59a473a2a71b59546cf3
parent faeea348d6245fd7625bcb718a583283bc09f99d
author Pau Espin Pedrol <pespin@sysmocom.de> 1531841956 +0200
committer Pau Espin Pedrol <pespin@sysmocom.de> 1531994951 +0000

sgsn: cdr: Fix uninitialized string access if ggsn is detached

if pdp->ggsn==NULL, sgsn_addr was not initialized and caused asan report
during snprintf:

==19459==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffffffbe31 at pc 0x7ffff6e563fe bp 0x7fffffffb130 sp 0x7fffffffa8a8
READ of size 31 at 0x7fffffffbe31 thread T0
...
Address 0x7fffffffbe31 is located in stack of thread T0 at offset 337 in frame
    #0 0x55555573a7b0 in cdr_snprintf_pdp osmo-sgsn/src/gprs/sgsn_cdr.c:154
...
[320, 337) 'sgsn_addr' <== Memory access at offset 337 overflows this variable
...

Change-Id: I97bc56a4e3e76725eb2717b74b3ac125b68bbf0a