From 1c8aa5318f13710defb4fb34288b8e6c444ac823 Mon Sep 17 00:00:00 2001
From: Aaron Marcher <info@nulltime.net>
Date: Tue, 13 Jun 2017 00:06:56 +0200
Subject: [PATCH] check for fgets/fscanf return values
---
slstatus.c | 110 ++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 75 insertions(+), 35 deletions(-)
diff --git a/slstatus.c b/slstatus.c
index b592446..af26fe7 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -99,7 +99,7 @@ bprintf(const char *fmt, ...)
static const char *
battery_perc(const char *bat)
{
- int perc;
+ int n, perc;
char path[PATH_MAX];
FILE *fp;
@@ -109,8 +109,10 @@ battery_perc(const char *bat)
warn("Failed to open file %s", path);
return UNKNOWN_STR;
}
- fscanf(fp, "%i", &perc);
+ n = fscanf(fp, "%i", &perc);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%d", perc);
}
@@ -120,7 +122,7 @@ battery_power(const char *bat)
{
char path[PATH_MAX];
FILE *fp;
- int watts;
+ int n, watts;
snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/power_now");
fp = fopen(path, "r");
@@ -128,8 +130,10 @@ battery_power(const char *bat)
warn("Failed to open file %s", path);
return UNKNOWN_STR;
}
- fscanf(fp, "%i", &watts);
+ n = fscanf(fp, "%i", &watts);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%d", (watts + 500000) / 1000000);
}
@@ -140,6 +144,7 @@ battery_state(const char *bat)
char path[PATH_MAX];
char state[12];
FILE *fp;
+ int n;
snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/status");
fp = fopen(path, "r");
@@ -147,8 +152,10 @@ battery_state(const char *bat)
warn("Failed to open file %s", path);
return UNKNOWN_STR;
}
- fscanf(fp, "%12s", state);
+ n = fscanf(fp, "%12s", state);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
if (strcmp(state, "Charging") == 0) {
return "+";
@@ -166,7 +173,7 @@ battery_state(const char *bat)
static const char *
cpu_freq(void)
{
- int freq;
+ int n, freq;
FILE *fp;
fp = fopen("/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq", "r");
@@ -174,8 +181,10 @@ cpu_freq(void)
warn("Failed to open file /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq");
return UNKNOWN_STR;
}
- fscanf(fp, "%i", &freq);
+ n = fscanf(fp, "%i", &freq);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%d", (freq + 500) / 1000);
}
@@ -183,7 +192,7 @@ cpu_freq(void)
static const char *
cpu_perc(void)
{
- int perc;
+ int n, perc;
long double a[4], b[4];
FILE *fp;
@@ -192,8 +201,10 @@ cpu_perc(void)
warn("Failed to open file /proc/stat");
return UNKNOWN_STR;
}
- fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
+ n = fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
fclose(fp);
+ if (n != 4)
+ return UNKNOWN_STR;
delay++;
sleep(delay);
@@ -203,8 +214,10 @@ cpu_perc(void)
warn("Failed to open file /proc/stat");
return UNKNOWN_STR;
}
- fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
+ n = fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
fclose(fp);
+ if (n != 4)
+ return UNKNOWN_STR;
perc = 100 * ((b[0]+b[1]+b[2]) - (a[0]+a[1]+a[2])) / ((b[0]+b[1]+b[2]+b[3]) - (a[0]+a[1]+a[2]+a[3]));
return bprintf("%d", perc);
@@ -280,7 +293,7 @@ disk_used(const char *mnt)
static const char *
entropy(void)
{
- int num;
+ int n, num;
FILE *fp;
fp= fopen("/proc/sys/kernel/random/entropy_avail", "r");
@@ -288,8 +301,10 @@ entropy(void)
warn("Failed to open file /proc/sys/kernel/random/entropy_avail");
return UNKNOWN_STR;
}
- fscanf(fp, "%d", &num);
+ n = fscanf(fp, "%d", &num);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%d", num);
}
@@ -392,14 +407,17 @@ ram_free(void)
{
long free;
FILE *fp;
+ int n;
fp = fopen("/proc/meminfo", "r");
if (fp == NULL) {
warn("Failed to open file /proc/meminfo");
return UNKNOWN_STR;
}
- fscanf(fp, "MemFree: %ld kB\n", &free);
+ n = fscanf(fp, "MemFree: %ld kB\n", &free);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%f", (float)free / 1024 / 1024);
}
@@ -415,13 +433,19 @@ ram_perc(void)
warn("Failed to open file /proc/meminfo");
return UNKNOWN_STR;
}
- fscanf(fp, "MemTotal: %ld kB\n", &total);
- fscanf(fp, "MemFree: %ld kB\n", &free);
- fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
- fscanf(fp, "Cached: %ld kB\n", &cached);
+ if (fscanf(fp, "MemTotal: %ld kB\n", &total) != 1 ||
+ fscanf(fp, "MemFree: %ld kB\n", &free) != 1 ||
+ fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n",
+ &buffers, &buffers) != 2 ||
+ fscanf(fp, "Cached: %ld kB\n", &cached) != 1)
+ goto scanerr;
fclose(fp);
return bprintf("%d", 100 * ((total - free) - (buffers + cached)) / total);
+
+scanerr:
+ fclose(fp);
+ return UNKNOWN_STR;
}
static const char *
@@ -429,14 +453,17 @@ ram_total(void)
{
long total;
FILE *fp;
+ int n;
fp = fopen("/proc/meminfo", "r");
if (fp == NULL) {
warn("Failed to open file /proc/meminfo");
return UNKNOWN_STR;
}
- fscanf(fp, "MemTotal: %ld kB\n", &total);
+ n = fscanf(fp, "MemTotal: %ld kB\n", &total);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%f", (float)total / 1024 / 1024);
}
@@ -452,19 +479,25 @@ ram_used(void)
warn("Failed to open file /proc/meminfo");
return UNKNOWN_STR;
}
- fscanf(fp, "MemTotal: %ld kB\n", &total);
- fscanf(fp, "MemFree: %ld kB\n", &free);
- fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
- fscanf(fp, "Cached: %ld kB\n", &cached);
+ if (fscanf(fp, "MemTotal: %ld kB\n", &total) != 1 ||
+ fscanf(fp, "MemFree: %ld kB\n", &free) != 1 ||
+ fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n",
+ &buffers, &buffers) != 2 ||
+ fscanf(fp, "Cached: %ld kB\n", &cached) != 1)
+ goto scanerr;
fclose(fp);
return bprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024);
+
+scanerr:
+ fclose(fp);
+ return UNKNOWN_STR;
}
static const char *
run_command(const char *cmd)
{
- char *nlptr;
+ char *p;
FILE *fp;
fp = popen(cmd, "r");
@@ -472,10 +505,12 @@ run_command(const char *cmd)
warn("Failed to get command output for %s", cmd);
return UNKNOWN_STR;
}
- fgets(buf, sizeof(buf) - 1, fp);
+ p = fgets(buf, sizeof(buf) - 1, fp);
pclose(fp);
- if ((nlptr = strrchr(buf, '\n')) != NULL)
- nlptr[0] = '\0';
+ if (!p)
+ return UNKNOWN_STR;
+ if ((p = strrchr(buf, '\n')) != NULL)
+ p[0] = '\0';
return buf[0] ? buf : UNKNOWN_STR;
}
@@ -613,7 +648,7 @@ swap_used(void)
static const char *
temp(const char *file)
{
- int temp;
+ int n, temp;
FILE *fp;
fp = fopen(file, "r");
@@ -621,8 +656,10 @@ temp(const char *file)
warn("Failed to open file %s", file);
return UNKNOWN_STR;
}
- fscanf(fp, "%d", &temp);
+ n = fscanf(fp, "%d", &temp);
fclose(fp);
+ if (n != 1)
+ return UNKNOWN_STR;
return bprintf("%d", temp / 1000);
}
@@ -697,8 +734,8 @@ vol_perc(const char *card)
static const char *
wifi_perc(const char *iface)
{
- int perc;
- char *datastart;
+ int i, perc;
+ char *p, *datastart;
char path[PATH_MAX];
char status[5];
FILE *fp;
@@ -709,9 +746,9 @@ wifi_perc(const char *iface)
warn("Failed to open file %s", path);
return UNKNOWN_STR;
}
- fgets(status, 5, fp);
+ p = fgets(status, 5, fp);
fclose(fp);
- if(strcmp(status, "up\n") != 0) {
+ if(!p || strcmp(status, "up\n") != 0) {
return UNKNOWN_STR;
}
@@ -721,10 +758,13 @@ wifi_perc(const char *iface)
return UNKNOWN_STR;
}
- fgets(buf, sizeof(buf) - 1, fp);
- fgets(buf, sizeof(buf) - 1, fp);
- fgets(buf, sizeof(buf) - 1, fp);
+ for (i = 0; i < 3; i++) {
+ if (!(p = fgets(buf, sizeof(buf) - 1, fp)))
+ break;
+ }
fclose(fp);
+ if (i < 2 || !p)
+ return UNKNOWN_STR;
if ((datastart = strstr(buf, iface)) == NULL)
return UNKNOWN_STR;
--
2.20.1