commit 68aee7ba66d390abf48c13791a84f6bce29d6f19
author Akinobu Mita <akinobu.mita@gmail.com> Wed Sep 18 21:27:27 2013 +0900
committer James Bottomley <JBottomley@Parallels.com> Fri Oct 25 09:58:12 2013 +0100
tree c382158f4a0fd15743ce6bda063a5bc81e7e89e1
parent 65f72f2a2fe89f072d6a88e5cd69a64270b9c436

[SCSI] scsi_debug: fix invalid value check for guard module parameter

In the module initialization, invalid value for guard module parameter
is detected by the following check:

        if (scsi_debug_guard > 1) {
                printk(KERN_ERR "scsi_debug_init: guard must be 0 or 1\n");
                return -EINVAL;
        }

But this check isn't enough, because the type of scsi_debug_guard is
'int' and scsi_debug_guard could be a negative value.

This fixes it by changing the type of scsi_debug_guard to 'unsigned int'
instead of adding extra check for a negative value.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/scsi_debug.c

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 43369e9..a21322d 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -169,7 +169,7 @@
 static int scsi_debug_dsense = DEF_D_SENSE;
 static int scsi_debug_every_nth = DEF_EVERY_NTH;
 static int scsi_debug_fake_rw = DEF_FAKE_RW;
-static int scsi_debug_guard = DEF_GUARD;
+static unsigned int scsi_debug_guard = DEF_GUARD;
 static int scsi_debug_lowest_aligned = DEF_LOWEST_ALIGNED;
 static int scsi_debug_max_luns = DEF_MAX_LUNS;
 static int scsi_debug_max_queue = SCSI_DEBUG_CANQUEUE;
@@ -2754,7 +2754,7 @@
 module_param_named(dsense, scsi_debug_dsense, int, S_IRUGO | S_IWUSR);
 module_param_named(every_nth, scsi_debug_every_nth, int, S_IRUGO | S_IWUSR);
 module_param_named(fake_rw, scsi_debug_fake_rw, int, S_IRUGO | S_IWUSR);
-module_param_named(guard, scsi_debug_guard, int, S_IRUGO);
+module_param_named(guard, scsi_debug_guard, uint, S_IRUGO);
 module_param_named(lbpu, scsi_debug_lbpu, int, S_IRUGO);
 module_param_named(lbpws, scsi_debug_lbpws, int, S_IRUGO);
 module_param_named(lbpws10, scsi_debug_lbpws10, int, S_IRUGO);
@@ -3184,7 +3184,7 @@
 
 static ssize_t sdebug_guard_show(struct device_driver *ddp, char *buf)
 {
-	return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_guard);
+	return scnprintf(buf, PAGE_SIZE, "%u\n", scsi_debug_guard);
 }
 DRIVER_ATTR(guard, S_IRUGO, sdebug_guard_show, NULL);