OSDN Git Service

s390/qeth: use vzalloc for QUERY OAT buffer
authorWenjia Zhang <wenjia@linux.ibm.com>
Wed, 12 Sep 2018 13:31:34 +0000 (15:31 +0200)
committerDavid S. Miller <davem@davemloft.net>
Wed, 12 Sep 2018 20:12:51 +0000 (13:12 -0700)
qeth_query_oat_command() currently allocates the kernel buffer for
the SIOC_QETH_QUERY_OAT ioctl with kzalloc. So on systems with
fragmented memory, large allocations may fail (eg. the qethqoat tool by
default uses 132KB).

Solve this issue by using vzalloc, backing the allocation with
non-contiguous memory.

Signed-off-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/s390/net/qeth_core_main.c

index b60055e..de82824 100644 (file)
@@ -25,6 +25,7 @@
 #include <linux/netdevice.h>
 #include <linux/netdev_features.h>
 #include <linux/skbuff.h>
+#include <linux/vmalloc.h>
 
 #include <net/iucv/af_iucv.h>
 #include <net/dsfield.h>
@@ -4699,7 +4700,7 @@ static int qeth_query_oat_command(struct qeth_card *card, char __user *udata)
 
        priv.buffer_len = oat_data.buffer_len;
        priv.response_len = 0;
-       priv.buffer =  kzalloc(oat_data.buffer_len, GFP_KERNEL);
+       priv.buffer = vzalloc(oat_data.buffer_len);
        if (!priv.buffer) {
                rc = -ENOMEM;
                goto out;
@@ -4740,7 +4741,7 @@ static int qeth_query_oat_command(struct qeth_card *card, char __user *udata)
                        rc = -EFAULT;
 
 out_free:
-       kfree(priv.buffer);
+       vfree(priv.buffer);
 out:
        return rc;
 }