s390/zcrypt: fix card and queue total counter wrap

The internal statistic counters for the total number of
requests processed per card and per queue used integers. So they do
wrap after a rather huge amount of crypto requests processed. This
patch introduces uint64 counters which should hold much longer but
still may wrap. The sysfs attributes request_count for card and queue
also used only %ld and now display the counter value with %llu.

This is not a security relevant fix. The int overflow which happened
is not in any way exploitable as a security breach.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Harald Freudenberger
2019-12-20 16:02:54 +01:00
committed by Vasily Gorbik
parent aab73d278d
commit fcd98d4002
4 changed files with 18 additions and 16 deletions

View File

@@ -606,8 +606,8 @@ static inline bool zcrypt_card_compare(struct zcrypt_card *zc,
weight += atomic_read(&zc->load);
pref_weight += atomic_read(&pref_zc->load);
if (weight == pref_weight)
return atomic_read(&zc->card->total_request_count) >
atomic_read(&pref_zc->card->total_request_count);
return atomic64_read(&zc->card->total_request_count) >
atomic64_read(&pref_zc->card->total_request_count);
return weight > pref_weight;
}
@@ -1226,11 +1226,12 @@ static void zcrypt_qdepth_mask(char qdepth[], size_t max_adapters)
spin_unlock(&zcrypt_list_lock);
}
static void zcrypt_perdev_reqcnt(int reqcnt[], size_t max_adapters)
static void zcrypt_perdev_reqcnt(u32 reqcnt[], size_t max_adapters)
{
struct zcrypt_card *zc;
struct zcrypt_queue *zq;
int card;
u64 cnt;
memset(reqcnt, 0, sizeof(int) * max_adapters);
spin_lock(&zcrypt_list_lock);
@@ -1242,8 +1243,9 @@ static void zcrypt_perdev_reqcnt(int reqcnt[], size_t max_adapters)
|| card >= max_adapters)
continue;
spin_lock(&zq->queue->lock);
reqcnt[card] = zq->queue->total_request_count;
cnt = zq->queue->total_request_count;
spin_unlock(&zq->queue->lock);
reqcnt[card] = (cnt < UINT_MAX) ? (u32) cnt : UINT_MAX;
}
}
local_bh_enable();
@@ -1421,9 +1423,9 @@ static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
return 0;
}
case ZCRYPT_PERDEV_REQCNT: {
int *reqcnt;
u32 *reqcnt;
reqcnt = kcalloc(AP_DEVICES, sizeof(int), GFP_KERNEL);
reqcnt = kcalloc(AP_DEVICES, sizeof(u32), GFP_KERNEL);
if (!reqcnt)
return -ENOMEM;
zcrypt_perdev_reqcnt(reqcnt, AP_DEVICES);
@@ -1480,7 +1482,7 @@ static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
}
case Z90STAT_PERDEV_REQCNT: {
/* the old ioctl supports only 64 adapters */
int reqcnt[MAX_ZDEV_CARDIDS];
u32 reqcnt[MAX_ZDEV_CARDIDS];
zcrypt_perdev_reqcnt(reqcnt, MAX_ZDEV_CARDIDS);
if (copy_to_user((int __user *) arg, reqcnt, sizeof(reqcnt)))