Pro tips for hooking up the function

[IzNoGoD]

*(char**)foo casts foo to a char-pointer-pointer. char-pointers are basically arrays of characters, more commonly referred to as strings. So a char-pointer-pointer is a string-pointer. The * in front of it dereferences the pointer, so it dereferences a char** into a char*.

The +0 is probably a leftover from trying different addresses near it.

[Whiskas]

Finally(?) got seg fault with your libcod's function:

[45709.850790] cod2_lnxded_1_0[1722]: segfault at 0 ip b7725b42 sp bf9a7330 error 4 in libcod2_1_0_hookLessSpam.so[b7711000+20000]
[45711.750596] UDP: bad checksum. From 197.1.146.216:28960 to 89.36.219.214:28960 ulen 45
[45715.700044] UDP: bad checksum. From 197.1.146.216:28960 to 89.36.219.214:28960 ulen 54
[45735.651877] UDP: bad checksum. From 197.1.146.216:28960 to 89.36.219.214:28960 ulen 77
[45739.513702] UDP: bad checksum. From 197.1.146.216:28960 to 89.36.219.214:28960 ulen 122

And the screen's log:

hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: enfield_scope_mp
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: kar98k_mp
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: none
hook_BG_IsWeaponValid -- Last weapon used: kar98k_sniper_mp
hook_BG_IsWeaponValid -- Last weapon used: webley_mp
Segmentation fault (core dumped)
==854== 
==854== HEAP SUMMARY:
==854==     in use at exit: 532 bytes in 27 blocks
==854==   total heap usage: 33 allocs, 6 frees, 1,137 bytes allocated
==854== 
==854== 16 bytes in 1 blocks are still reachable in loss record 1 of 5
==854==    at 0x482A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x1140CA: ??? (in /bin/dash)
==854==    by 0x11B2FD: ??? (in /bin/dash)
==854==    by 0x11BD98: ??? (in /bin/dash)
==854==    by 0x10AD6F: main (in /bin/dash)
==854== 
==854== 16 bytes in 1 blocks are still reachable in loss record 2 of 5
==854==    at 0x482A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x48BC9C7: strdup (strdup.c:42)
==854==    by 0x11414A: ??? (in /bin/dash)
==854==    by 0x10C179: ??? (in /bin/dash)
==854==    by 0x11BDC3: ??? (in /bin/dash)
==854==    by 0x10AD6F: main (in /bin/dash)
==854== 
==854== 20 bytes in 1 blocks are still reachable in loss record 3 of 5
==854==    at 0x482A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x1140CA: ??? (in /bin/dash)
==854==    by 0x11B3E6: ??? (in /bin/dash)
==854==    by 0x10C1C0: ??? (in /bin/dash)
==854==    by 0x11BDC3: ??? (in /bin/dash)
==854==    by 0x10AD6F: main (in /bin/dash)
==854== 
==854== 112 bytes in 1 blocks are still reachable in loss record 4 of 5
==854==    at 0x482A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x482C3AF: realloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x114112: ??? (in /bin/dash)
==854==    by 0x1135D9: ??? (in /bin/dash)
==854==    by 0x10DCD0: ??? (in /bin/dash)
==854==    by 0x10CA06: ??? (in /bin/dash)
==854==    by 0x113E37: ??? (in /bin/dash)
==854==    by 0x10ADEF: main (in /bin/dash)
==854== 
==854== 368 bytes in 23 blocks are still reachable in loss record 5 of 5
==854==    at 0x482A17C: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==854==    by 0x1140CA: ??? (in /bin/dash)
==854==    by 0x11B2FD: ??? (in /bin/dash)
==854==    by 0x11BD53: ??? (in /bin/dash)
==854==    by 0x10AD6F: main (in /bin/dash)
==854== 
==854== LEAK SUMMARY:
==854==    definitely lost: 0 bytes in 0 blocks
==854==    indirectly lost: 0 bytes in 0 blocks
==854==      possibly lost: 0 bytes in 0 blocks
==854==    still reachable: 532 bytes in 27 blocks
==854==         suppressed: 0 bytes in 0 blocks
==854== 
==854== For counts of detected and suppressed errors, rerun with: -v
==854== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
==12416== Memcheck, a memory error detector
==12416== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==12416== Using Valgrind-3.10.1 and LibVEX; rerun with -h for copyright info
==12416== Command: ./start
==12416== 
> [INFO] Compiled for: CoD2 1.0
Compiled: May  4 2016 17:05:07 using GCC 4.8.4
> [PLUGIN LOADED]
CoD2 MP 1.0 build linux-i386 Oct 24 2005
----- FS_Startup -----
Current search path:

I don't really think that webley is causing the problem :|. And yes it was used before without segfault.