Re: [libvirt] [PATCH 5/n] security: plug memory leak

security_context_t happens to be a typedef for char*, and happens to begin with a string usable as a raw context string.  But in reality, it is an opaque type that may or may not have additional information after the first NUL byte, where that additional information can include pointers that can only be freed via freecon(). Proof is from this valgrind run of daemon/libvirtd: ==6028== 839,169 (40 direct, 839,129 indirect) bytes in 1 blocks are definitely lost in loss record 274 of 274 ==6028==    at 0x4A0515D: malloc (vg_replace_malloc.c:195) ==6028==    by 0x3022E0D48C: selabel_open (label.c:165) ==6028==    by 0x3022E11646: matchpathcon_init_prefix (matchpathcon.c:296) ==6028==    by 0x3022E1190D: matchpathcon (matchpathcon.c:317) ==6028==    by 0x4F9D842: SELinuxRestoreSecurityFileLabel (security_selinux.c:382) 800k is a lot of memory to be leaking. * src/security/security_selinux.c (SELinuxReserveSecurityLabel, SELinuxGetSecurityProcessLabel) (SELinuxRestoreSecurityFileLabel): Use correct function to free security_context_t.