mcelog/backport-assign-freed-pointers-to-NULL-pointer.patch

From 283fe6b239b140093bc142a9ff2c947dd54c754c Mon Sep 17 00:00:00 2001
From: Hui Li <herdingcat@yahoo.com>
Date: Sat, 23 Dec 2023 21:13:29 -0500
Subject: [PATCH] assign freed pointers to NULL pointer

---
 bus.c     | 13 ++++++++++---
 cache.c   |  3 +++
 config.c  | 10 ++++++++++
 dimm.c    |  1 +
 dmi.c     |  1 +
 mcelog.c  |  7 ++++++-
 memdb.c   | 11 ++++++++++-
 msg.c     |  2 ++
 msr.c     |  1 +
 page.c    | 15 +++++++++++++--
 server.c  |  6 +++++-
 sysfs.c   |  7 +++++++
 trigger.c |  7 +++++--
 tsc.c     |  4 ++++
 unknown.c |  6 +++++-
 yellow.c  |  6 +++++-
 16 files changed, 88 insertions(+), 12 deletions(-)

diff --git a/bus.c b/bus.c
index 20b4741..2bf2d9a 100644
--- a/bus.c
+++ b/bus.c
@@ -69,6 +69,7 @@ void run_bus_trigger(int socket, int cpu, char *level, char *pp, char *rrrr,
 		location, ii);
 	xasprintf(&env[ei++], "LOCATION=%s", location);
 	free(location);
+	location = NULL;
 
 	if (socket >= 0)
 		xasprintf(&env[ei++], "SOCKETID=%d", socket);
@@ -83,9 +84,12 @@ void run_bus_trigger(int socket, int cpu, char *level, char *pp, char *rrrr,
 	assert(ei < MAX_ENV);
 
 	run_trigger(bus_trigger, NULL, env, false, "bus");
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 	free(msg);
+	msg = NULL;
 }
 
 void run_iomca_trigger(int socket, int cpu, int seg, int bus, int dev, int fn)
@@ -107,6 +111,7 @@ void run_iomca_trigger(int socket, int cpu, int seg, int bus, int dev, int fn)
 		location, seg, bus, dev, fn);
 	xasprintf(&env[ei++], "LOCATION=%s", location);
 	free(location);
+	location = NULL;
 
 	if (socket >= 0)
 		xasprintf(&env[ei++], "SOCKETID=%d", socket);
@@ -120,8 +125,10 @@ void run_iomca_trigger(int socket, int cpu, int seg, int bus, int dev, int fn)
 	assert(ei < MAX_ENV);
 
 	run_trigger(iomca_trigger, NULL, env, false, "iomca");
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 	free(msg);
-
+	msg = NULL;
 }
diff --git a/cache.c b/cache.c
index 8b64b43..74c0d31 100644
--- a/cache.c
+++ b/cache.c
@@ -108,6 +108,7 @@ static void read_cpu_map(struct cache *c, char *cfn)
 	parse_cpumap(map, c->cpumap, c->cpumaplen);
 out:
 	free(map);
+	map = NULL;
 }
 
 static int read_caches(void)
@@ -144,9 +145,11 @@ static int read_caches(void)
 					c->level = read_field_num(cfn, "level");
 					read_cpu_map(c, cfn);
 					free(cfn);
+					cfn = NULL;
 				}
 			}
 			free(fn);
+			fn = NULL;
 		}
 	}
 	closedir(cpus);
diff --git a/config.c b/config.c
index cefc220..df94594 100644
--- a/config.c
+++ b/config.c
@@ -110,6 +110,7 @@ static void unparseable(char *desc, const char *header, const char *name)
 	}
 	Eprintf("%s config option `%s' unparseable\n", desc, field);
 	free(field);
+	field = NULL;
 	exit(1);
 }
 
@@ -180,6 +181,7 @@ int parse_config_file(const char *fn)
 	}
 	fclose(f);
 	free(line);
+	line = NULL;
 	return 0;
 }
 
@@ -302,6 +304,7 @@ int config_trigger(const char *header, const char *base, struct bucket_conf *bc)
 		}
 	}
 	free(name);
+	name = NULL;
 
 	xasprintf(&name, "%s-trigger", base);
 	s = config_string(header, name);
@@ -314,6 +317,7 @@ int config_trigger(const char *header, const char *base, struct bucket_conf *bc)
 		bc->trigger = s;
 	}
 	free(name);
+	name = NULL;
 
 	bc->log = 0;
 	xasprintf(&name, "%s-log", base);
@@ -321,6 +325,7 @@ int config_trigger(const char *header, const char *base, struct bucket_conf *bc)
 	if (n >= 0)
 		bc->log = n;
 	free(name);
+	name = NULL;
 
 	return 0;
 }
@@ -342,6 +347,7 @@ void config_cred(char *header, char *base, struct config_cred *cred)
 		        cred->uid = pw->pw_uid;
 	}
 	free(name);
+	name = NULL;
 	xasprintf(&name, "%s-group", base);	
 	if ((s = config_string(header, name)) != NULL) { 
 		struct group *gr;
@@ -354,6 +360,7 @@ void config_cred(char *header, char *base, struct config_cred *cred)
 			cred->gid = gr->gr_gid;
 	}
 	free(name);
+	name = NULL;
 }
 
 #ifdef TEST
@@ -386,8 +393,11 @@ int main(int ac, char **av)
 			break;
 		}
 		free(type);
+		type = NULL;
 		free(header);
+		header = NULL;
 		free(name);
+		name = NULL;
 	} 
 	return 0;
 }
diff --git a/dimm.c b/dimm.c
index 7edb6b3..22ada68 100644
--- a/dimm.c
+++ b/dimm.c
@@ -378,6 +378,7 @@ void new_error(unsigned long long addr, unsigned long max_error, char *trigger)
 		}
 	}
 	free(devs);
+	devs = NULL;
 }
 
 void reset_dimm(char *locator)
diff --git a/dmi.c b/dmi.c
index 2970e77..a6ace3b 100644
--- a/dmi.c
+++ b/dmi.c
@@ -667,6 +667,7 @@ void dmi_decodeaddr(unsigned long long addr)
 		Wprintf("No DIMM found for %llx in SMBIOS\n", addr);
 	}
 	free(devs);
+	devs = NULL;
 } 
 
 void dmi_set_verbosity(int v)
diff --git a/mcelog.c b/mcelog.c
index 2948ea7..a0230b7 100644
--- a/mcelog.c
+++ b/mcelog.c
@@ -165,6 +165,7 @@ static void print_tsc(int cpunum, __u64 tsc, unsigned long time)
 		ret = decode_tsc_current(&buf, cpunum, cputype, cpumhz, tsc);
 	Wprintf("TSC %llx %s", tsc, ret >= 0 && buf ? buf : "");
 	free(buf);
+	buf = NULL;
 }
 
 struct cpuid1 {
@@ -477,6 +478,7 @@ int is_cpu_supported(void)
 		} 
 		fclose(f);
 		free(line);
+		line = NULL;
 	} else
 		Eprintf("warning: Cannot open /proc/cpuinfo\n");
 
@@ -805,6 +807,7 @@ restart:
 			data = 1;
 	} 
 	free(line);
+	line = NULL;
 	if (data)
 		dump_mce_final(&m, symbol, missing, recordlen, disclaimer_seen);
 }
@@ -812,8 +815,10 @@ restart:
 static void remove_pidfile(void)
 {
 	unlink(pidfile);
-	if (pidfile != pidfile_default)
+	if (pidfile != pidfile_default) {
 		free(pidfile);
+		pidfile = NULL;
+	}
 }
 
 static void signal_exit(int sig)
diff --git a/memdb.c b/memdb.c
index 8dfe15d..956704f 100644
--- a/memdb.c
+++ b/memdb.c
@@ -174,12 +174,17 @@ void memdb_trigger(char *msg, struct memdimm *md,  time_t t,
 	env[ei] = NULL;	
 	assert(ei < MAX_ENV);
 	run_trigger(bc->trigger, args, env, sync, reporter);
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 out:
 	free(location);
+	location = NULL;
 	free(out);
+	out = NULL;
 	free(thresh);
+	thresh = NULL;
 }
 
 /* 
@@ -197,6 +202,7 @@ account_over(struct err_triggers *t, struct memdimm *md, struct mce *m, unsigned
 				 t->type, corr_err_cnt);
 			memdb_trigger(msg, md, 0, &md->ce, &t->ce_bucket_conf, NULL, false, reporter);
 			free(msg);
+			msg = NULL;
 		}
 	}
 }
@@ -219,6 +225,7 @@ account_memdb(struct err_triggers *t, struct memdimm *md, struct mce *m, const c
 			memdb_trigger(msg, md, m->time, &md->ce, &t->ce_bucket_conf, NULL, false, reporter);
 	}
 	free(msg);
+	msg = NULL;
 }
 
 /* 
@@ -281,6 +288,7 @@ static void dump_errtype(char *name, struct err_type *e, FILE *f, enum printflag
 		s = bucket_output(bc, &e->bucket);
 		fprintf(f, "\t%s\n", s);  
 		free(s);
+		s = NULL;
 	}
 }
 
@@ -343,6 +351,7 @@ void dump_memory_errors(FILE *f, enum printflags flags)
 		dump_dimm(da[i], f, flags);
 	}
 	free(da);
+	da = NULL;
 }
 
 void memdb_config(void)
diff --git a/msg.c b/msg.c
index fd54f20..e564a3d 100644
--- a/msg.c
+++ b/msg.c
@@ -26,6 +26,7 @@ int open_logfile(char *fn)
 		char *old = output_fn;
 		output_fn = xstrdup(fn);
 		free(old);
+		old = NULL;
 		return 0;
 	}
 	return -1;
@@ -100,6 +101,7 @@ void SYSERRprintf(char *fmt, ...)
 		xasprintf(&fmt2, "%s: %s\n", fmt, err);
 		vsyslog(LOG_ERR, fmt2, ap);
 		free(fmt2);
+		fmt2 = NULL;
 		va_end(ap);
 	}
 }
diff --git a/msr.c b/msr.c
index a5bba8a..54cddc5 100644
--- a/msr.c
+++ b/msr.c
@@ -56,6 +56,7 @@ static bool in_lockdown(void)
 	if (!strstr(lockdown, "[none]"))
 		ret = true;
 	free(lockdown);
+	lockdown = NULL;
 	return ret;
 }
 
diff --git a/page.c b/page.c
index 3a0dfb7..eff42b0 100644
--- a/page.c
+++ b/page.c
@@ -265,11 +265,15 @@ static void counter_trigger(char *msg, time_t t, struct mempage_replacement *mr,
 
 	run_trigger(bc->trigger, NULL, env, sync, "page-error-counter");
 
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 out:
 	free(out);
+	out = NULL;
 	free(thresh);
+	thresh = NULL;
 }
 
 void account_page_error(struct mce *m, int channel, int dimm)
@@ -323,9 +327,11 @@ void account_page_error(struct mce *m, int channel, int dimm)
 			thresh = bucket_output(&mp_replacement_trigger_conf, &mp_repalcement.bucket);
 			xasprintf(&msg, "Replacements of page correctable error counter exceed threshold %s", thresh);
 			free(thresh);
+			thresh = NULL;
 
 			counter_trigger(msg, t, &mp_repalcement, &mp_replacement_trigger_conf, false);
 			free(msg);
+			msg = NULL;
 		}
 	} else {
 		mempage_cluster_lru_list_update(to_cluster(mp));
@@ -342,8 +348,10 @@ void account_page_error(struct mce *m, int channel, int dimm)
 		xasprintf(&msg, "Corrected memory errors on page %llx exceed threshold %s",
 			addr, thresh);
 		free(thresh);
+		thresh = NULL;
 		memdb_trigger(msg, md, t, &mp->ce, &page_trigger_conf, NULL, false, "page");
 		free(msg);
+		msg = NULL;
 		mp->triggered = 1;
 
 		if (offline == OFFLINE_SOFT || offline == OFFLINE_SOFT_THEN_HARD) {
@@ -365,6 +373,7 @@ void account_page_error(struct mce *m, int channel, int dimm)
 			asprintf(&msg, "pre soft trigger run for page %lld", addr);
 			memdb_trigger(msg, md, t, &mp->ce, &page_soft_trigger_conf, argv, true, "page_pre_soft");
 			free(msg);
+			msg = NULL;
 
 			offline_action(mp, addr);
 
@@ -375,8 +384,9 @@ void account_page_error(struct mce *m, int channel, int dimm)
 			asprintf(&msg, "post soft trigger run for page %lld", addr);
 			memdb_trigger(msg, md, t, &mp->ce, &page_soft_trigger_conf, argv, true, "page_post_soft");
 			free(msg);
+			msg = NULL;
 			free(args);
-
+			args = NULL;
 		} else
 			offline_action(mp, addr);
 	}
@@ -402,6 +412,7 @@ void dump_page_errors(FILE *f)
 			page_state[(unsigned)p->offlined],
 			p->triggered ? " triggered" : "");
 		free(msg);
+		msg = NULL;
 		fputc('\n', f);
 	}
 }
diff --git a/server.c b/server.c
index 86029c5..54c7d57 100644
--- a/server.c
+++ b/server.c
@@ -70,8 +70,11 @@ static void free_inbuf(struct clientcon *cc)
 static void free_cc(struct clientcon *cc)
 {
 	free(cc->outbuf);
+	cc->outbuf = NULL;
 	free(cc->inbuf);
-	free(cc);	
+	cc->inbuf = NULL;
+	free(cc);
+	cc = NULL;
 }
 
 static void sendstring(int fd, char *str)
@@ -264,6 +267,7 @@ static void client_accept(struct pollfd *pfd, void *data)
 
 cleanup:
 	free(cc);
+	cc = NULL;
 	close(nfd);
 }
 
diff --git a/sysfs.c b/sysfs.c
index cd0f7c7..618d2bf 100644
--- a/sysfs.c
+++ b/sysfs.c
@@ -37,6 +37,7 @@ char *read_field(char *base, char *name)
 	xasprintf(&fn, "%s/%s", base, name);
 	fd = open(fn, O_RDONLY);
 	free(fn);
+	fn = NULL;
 	if (fd < 0)
 		goto bad_buf;
 	n = read(fd, buf, 4096);
@@ -47,6 +48,7 @@ char *read_field(char *base, char *name)
 	memcpy(val, buf, n);
 	val[n] = 0;
 	free(buf);
+	buf = NULL;
 	s = memchr(val, '\n', n);
 	if (s)
 		*s = 0;
@@ -54,6 +56,7 @@ char *read_field(char *base, char *name)
 
 bad_buf:
 	free(buf);
+	buf = NULL;
 	SYSERRprintf("Cannot read sysfs field %s/%s", base, name);
 	return xstrdup("");
 }
@@ -64,6 +67,7 @@ unsigned read_field_num(char *base, char *name)
 	char *val = read_field(base, name);
 	int n = sscanf(val, "%u", &num);
 	free(val);
+	val = NULL;
 	if (n != 1) { 
 		Eprintf("Cannot parse number in sysfs field %s/%s\n", base,name);
 		return 0;
@@ -81,10 +85,12 @@ unsigned read_field_map(char *base, char *name, struct map *map)
 	}
 	if (map->name) {
 		free(val);
+		val = NULL;
 		return map->value;
 	}
 	Eprintf("sysfs field %s/%s has unknown string value `%s'\n", base, name, val);
 	free(val);
+	val = NULL;
 	return -1;
 }
 
@@ -104,6 +110,7 @@ int sysfs_write(const char *name, const char *fmt, ...)
 	e = errno;
 	close(fd);
 	free(buf);
+	buf = NULL;
 	errno = e;
 	return n;
 }
diff --git a/trigger.c b/trigger.c
index 6480c58..4886680 100644
--- a/trigger.c
+++ b/trigger.c
@@ -108,7 +108,8 @@ static void finish_child(pid_t child, int status)
 					c->name, strsignal(WTERMSIG(status)));
 			}
 			list_del(&c->nd);
-			free(c);		
+			free(c);
+			c = NULL;
 			num_children--;
 			return;
 		}
@@ -175,8 +176,10 @@ int trigger_check(char *s)
 
 	rc = access(name, R_OK|X_OK);
 
-	if (trigger_dir)
+	if (trigger_dir) {
 		free(name);
+		name = NULL;
+	}
 
 	return rc;
 }
diff --git a/tsc.c b/tsc.c
index f79aaf0..db2b152 100644
--- a/tsc.c
+++ b/tsc.c
@@ -55,6 +55,7 @@ static double cpufreq_mhz(int cpu, double infomhz)
 	xasprintf(&fn, "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_max_freq", cpu);
 	f = fopen(fn, "r");
 	free(fn);
+	fn = NULL;
 	if (!f) {
 		/* /sys exists, but no cpufreq -- use value from cpuinfo */
 		if (access("/sys/devices", F_OK) == 0)
@@ -87,12 +88,14 @@ static int deep_sleep_states(int cpu)
 	xasprintf(&fn, "/sys/devices/system/cpu/cpu%d/cpuidle", cpu);
 	ret = access(fn, X_OK);
 	free(fn);
+	fn = NULL;
 	if (ret == 0)
 		return 1;
 
 	xasprintf(&fn, "/proc/acpi/processor/CPU%d/power", cpu);
 	f = fopen(fn, "r");
 	free(fn);
+	fn = NULL;
 	if (!f)
 		return 0;
 
@@ -107,6 +110,7 @@ static int deep_sleep_states(int cpu)
 		}
 	}
 	free(line);
+	line = NULL;
 	fclose(f);
 	return 0;
 }
diff --git a/unknown.c b/unknown.c
index 12feac8..f9d57a3 100644
--- a/unknown.c
+++ b/unknown.c
@@ -60,6 +60,7 @@ void run_unknown_trigger(int socket, int cpu, struct mce *log)
 	xasprintf(&msg, "%s received unknown error", location);
 	xasprintf(&env[ei++], "LOCATION=%s", location);
 	free(location);
+	location = NULL;
 
 	if (socket >= 0)
 		xasprintf(&env[ei++], "SOCKETID=%d", socket);
@@ -74,8 +75,11 @@ void run_unknown_trigger(int socket, int cpu, struct mce *log)
 	assert(ei < MAX_ENV);
 
 	run_trigger(unknown_trigger, NULL, env, false, "unknown");
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 	free(msg);
+	msg = NULL;
 }
 
diff --git a/yellow.c b/yellow.c
index 3616a8b..d73ab70 100644
--- a/yellow.c
+++ b/yellow.c
@@ -75,6 +75,7 @@ void run_yellow_trigger(int cpu, int tnum, int lnum, char *ts, char *ls, int soc
 	xasprintf(&msg, "%s has large number of corrected cache errors in %s %s",
 		location, ls, ts);
 	free(location);
+	location = NULL;
 	if (yellow_log) {
 		Lprintf("%s\n", msg);
 		Lprintf("System operating correctly, but might lead to uncorrected cache errors soon\n");
@@ -96,10 +97,13 @@ void run_yellow_trigger(int cpu, int tnum, int lnum, char *ts, char *ls, int soc
 	assert(ei < MAX_ENV);
 
 	run_trigger(yellow_trigger, NULL, env, false, "yellow");
-	for (i = 0; i < ei; i++)
+	for (i = 0; i < ei; i++) {
 		free(env[i]);
+		env[i] = NULL;
+	}
 out:
 	free(msg);
+	msg = NULL;
 }
 
 void yellow_setup(void)
-- 
2.33.0