swsusp: fix sysfs interface

The sysfs files /sys/power/disk and /sys/power/state do not work as documented, since they allow the user to write only a few initial characters of the input string to trigger the option (eg. 'echo pl > /sys/power/disk' activates the platform mode of hibernation). Fix it. Special thanks to Peter Moulder <[email protected]> for pointing out the problem. Signed-off-by: Rafael J. Wysocki <[email protected]> Acked-by: Pavel Machek <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mna · May 17, 2007 · 8d98a69 · 8d98a69
1 parent 7925409
commit 8d98a69
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Showing 2 changed files with 4 additions and 3 deletions.
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
@@ -416,7 +416,8 @@ static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
 
 	mutex_lock(&pm_mutex);
 	for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
-		if (!strncmp(buf, hibernation_modes[i], len)) {
+		if (len == strlen(hibernation_modes[i])
+		    && !strncmp(buf, hibernation_modes[i], len)) {
 			mode = i;
 			break;
 		}

diff --git a/kernel/power/main.c b/kernel/power/main.c
@@ -290,13 +290,13 @@ static ssize_t state_store(struct kset *kset, const char *buf, size_t n)
 	len = p ? p - buf : n;
 
 	/* First, check if we are requested to hibernate */
-	if (!strncmp(buf, "disk", len)) {
+	if (len == 4 && !strncmp(buf, "disk", len)) {
 		error = hibernate();
 		return error ? error : n;
 	}
 
 	for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) {
-		if (*s && !strncmp(buf, *s, len))
+		if (*s && len == strlen(*s) && !strncmp(buf, *s, len))
 			break;
 	}
 	if (state < PM_SUSPEND_MAX && *s)