s390/cio: fix measurement characteristics memleak

Measurement characteristics are allocated during channel path
registration but not freed during deregistration. Fix this by
embedding these characteristics inside struct channel_path.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

3 files changed, 6 insertions, 18 deletions

diff --git a/drivers/s390/cio/chp.c b/drivers/s390/cio/chp.c
index c692dfebd0ba..3d2b6c48c18e 100644
--- a/drivers/s390/cio/chp.c
+++ b/drivers/s390/cio/chp.c
@@ -139,11 +139,11 @@ static ssize_t chp_measurement_chars_read(struct file *filp,
 
         device = container_of(kobj, struct device, kobj);
         chp = to_channelpath(device);
-        if (!chp->cmg_chars)
+        if (chp->cmg == -1)
                 return 0;
 
-        return memory_read_from_buffer(buf, count, &off,
-                                chp->cmg_chars, sizeof(struct cmg_chars));
+        return memory_read_from_buffer(buf, count, &off, &chp->cmg_chars,
+                                       sizeof(chp->cmg_chars));
 }
 
 static struct bin_attribute chp_measurement_chars_attr = {
diff --git a/drivers/s390/cio/chp.h b/drivers/s390/cio/chp.h
index 4efd5b867cc3..af0232290dc4 100644
--- a/drivers/s390/cio/chp.h
+++ b/drivers/s390/cio/chp.h
@@ -48,7 +48,7 @@ struct channel_path {
         /* Channel-measurement related stuff: */
         int cmg;
         int shared;
-        void *cmg_chars;
+        struct cmg_chars cmg_chars;
 };
 
 /* Return channel_path struct for given chpid. */
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index a831d18596a5..5df0efee54db 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -967,22 +967,19 @@ static void
 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
                           struct cmg_chars *chars)
 {
-        struct cmg_chars *cmg_chars;
         int i, mask;
 
-        cmg_chars = chp->cmg_chars;
         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
                 mask = 0x80 >> (i + 3);
                 if (cmcv & mask)
-                        cmg_chars->values[i] = chars->values[i];
+                        chp->cmg_chars.values[i] = chars->values[i];
                 else
-                        cmg_chars->values[i] = 0;
+                        chp->cmg_chars.values[i] = 0;
         }
 }
 
 int chsc_get_channel_measurement_chars(struct channel_path *chp)
 {
-        struct cmg_chars *cmg_chars;
         int ccode, ret;
 
         struct {
@@ -1006,11 +1003,6 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp)
                 u32 data[NR_MEASUREMENT_CHARS];
         } __attribute__ ((packed)) *scmc_area;
 
-        chp->cmg_chars = NULL;
-        cmg_chars = kmalloc(sizeof(*cmg_chars), GFP_KERNEL);
-        if (!cmg_chars)
-                return -ENOMEM;
-
         spin_lock_irq(&chsc_page_lock);
         memset(chsc_page, 0, PAGE_SIZE);
         scmc_area = chsc_page;
@@ -1042,14 +1034,10 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp)
                 /* No cmg-dependent data. */
                 goto out;
         }
-        chp->cmg_chars = cmg_chars;
         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
                                   (struct cmg_chars *) &scmc_area->data);
 out:
         spin_unlock_irq(&chsc_page_lock);
-        if (!chp->cmg_chars)
-                kfree(cmg_chars);
-
         return ret;
 }