test failure because of a global-buffer-overflow

[asarubbo]

Our Gentoo Tinderbox reported a test failure at bug 914093

Looking at the LastTest.log I can see there are two different buffer overflow.

==102==ERROR: AddressSanitizer: global-buffer-overflow on address 0x560e33c69072 at pc 0x7f84a8b4455e bp 0x7ffcd45b5c60 sp 0x7ffcd45b5c50
READ of size 1 at 0x560e33c69072 thread T0
    #0 0x7f84a8b4455d in GSM_UnpackEightBitsToSeven /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/misc/coding/coding.c:1003
    #1 0x7f84a8b4bc68 in GSM_DecodeSMSFrameText /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/service/sms/gsmsms.c:354
    #2 0x7f84a8b5055d in GSM_DecodeSMSFrame /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/service/sms/gsmsms.c:855
    #3 0x560e33b1a715 in main /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/tests/sms-nokia-01.c:47
    #4 0x7f84a8823c89  (/lib64/libc.so.6+0x23c89)
    #5 0x7f84a8823d44 in __libc_start_main (/lib64/libc.so.6+0x23d44)
    #6 0x560e33b1a8c0 in _start (/var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0_build/tests/sms-nokia-01+0x248c0)

0x560e33c69072 is located 0 bytes after global variable 'data' defined in '/var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/tests/sms-nokia-01.c:13:15' (0x560e33c69040) of size 50
SUMMARY: AddressSanitizer: global-buffer-overflow /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/misc/coding/coding.c:1003 in GSM_UnpackEightBitsToSeven

==809==ERROR: AddressSanitizer: global-buffer-overflow on address 0x7ff162562e22 at pc 0x7ff162257d61 bp 0x7ffd51bd2480 sp 0x7ffd51bd2470
READ of size 2 at 0x7ff162562e22 thread T0
    #0 0x7ff162257d60 in mywstrstr /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/misc/coding/coding.c:1594
    #1 0x7ff16255a892 in SMSDFiles_FindOutboxSMS /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/services/files.c:386
    #2 0x7ff162555996 in SMSD_SendSMS /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/core.c:1684
    #3 0x7ff162557df7 in SMSD_MainLoop /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/core.c:2338
    #4 0x55949cc1e7e2 in main /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/main.c:517
    #5 0x7ff161e23c89  (/lib64/libc.so.6+0x23c89)
    #6 0x7ff161e23d44 in __libc_start_main (/lib64/libc.so.6+0x23d44)
    #7 0x55949cc1ea60 in _start (/var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0_build/smsd/gammu-smsd+0x21a60)

0x7ff162562e23 is located 0 bytes after global variable '*.LC35' defined in '/var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/services/files.c' (0x7ff162562e20) of size 3
0x7ff162562e22 is located 62 bytes before global variable '*.LC36' defined in '/var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/smsd/services/files.c' (0x7ff162562e60) of size 85
  '*.LC36' is ascii string 'Found %i sms to "%s" with bookmark "%s" cod %i lgt %i udh: t %i l %i dlr: %i fls: %i'
SUMMARY: AddressSanitizer: global-buffer-overflow /var/tmp/portage/app-mobilephone/gammu-1.42.0-r1/work/gammu-1.42.0/libgammu/misc/coding/coding.c:1594 in mywstrstr

I didn't look deeply into these issues but they appear to be related to libgammu, and then there are possible security implications/impacts.
If I can do more, please let me know.