Patch "[PATCH 059/135] s390/cio: fix measurement characteristics memleak" has been added to the 4.4-stable tree

Patch "[PATCH 059/135] s390/cio: fix measurement characteristics memleak" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    [PATCH 059/135] s390/cio: fix measurement characteristics memleak

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     0059-s390-cio-fix-measurement-characteristics-memleak.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From b25aac2e34a9783d2fde366d9ce12a8c0d525f50 Mon Sep 17 00:00:00 2001
From: Sebastian Ott <sebott@linux.vnet.ibm.com>
Date: Mon, 25 Jan 2016 10:30:27 +0100
Subject: [PATCH 059/135] s390/cio: fix measurement characteristics memleak

[ Upstream commit 0d9bfe9123cfde59bf5c2e375b59d2a7d5061c4c ]

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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/s390/cio/chp.c  |    6 +++---
 drivers/s390/cio/chp.h  |    2 +-
 drivers/s390/cio/chsc.c |   16 ++--------------
 3 files changed, 6 insertions(+), 18 deletions(-)

--- a/drivers/s390/cio/chp.c
+++ b/drivers/s390/cio/chp.c
@@ -139,11 +139,11 @@ static ssize_t chp_measurement_chars_rea
 
 	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 = {
--- 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. */
--- 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(s
 		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(s
 		/* 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;
 }
 


Patches currently in stable-queue which might be from sebott@linux.vnet.ibm.com are

queue-4.4/0059-s390-cio-fix-measurement-characteristics-memleak.patch
queue-4.4/0061-s390-cio-update-measurement-characteristics.patch
queue-4.4/0094-s390-pci_dma-fix-DMA-table-corruption-with-4-TB-main.patch
queue-4.4/0060-s390-cio-ensure-consistent-measurement-state.patch