sensorsd: memory leak and unnecessary exit

I have a host which uses sensorsd which periodically stops running, which
prompted me to dig into the cause, it's one or both of these two issues:

(1) memory leak on configuration reload, lines 753-758:

if (cgetstr(buf, "command", &ebuf) < 0)
    ebuf = NULL;
if (ebuf != NULL) {
    p->command = ebuf;
    ebuf = NULL;
}

cgetstr allocates a new ebuf and the previous pointer is overwritten
without freeing the old one.

Fix: insert free(p->command) before p->command = ebuf:

if (cgetstr(buf, "command", &ebuf) < 0)
    ebuf = NULL;
if (ebuf != NULL) {
    free(p->command);
    p->command = ebuf;
    ebuf = NULL;
}

(2) unnecessary exit in check_sdlim lines 367-368 for individual
sensor failure that is handled differently from the same code in
create_sdlim; sensorsd shouldn't be aborting because of a sysctl
failure on one sensor.

		if (sysctl(mib, 5, &sensor, &len, NULL, 0) == -1)
			err(1, "sysctl");

vs. create_sdlim, lines 240-243:

			if (sysctl(mib, 5, &sensor, &slen, NULL, 0) == -1) {
				if (errno != ENOENT)
					warn("sysctl");
				continue;
			}

Fix: make check_sdlim code equivalent to create_sdlim:

                if (sysctl(mib, 5, &sensor, &len, NULL, 0) == -1) {
		        if (errno != ENOENT)
			        warn("sysctl");
			continue;
		}

-- 
Jim Lippard        [email protected]       http://www.discord.org/
GPG Key ID: 0x99FD5CD6