commit d59342eb8db8c6761e17bb2bc387802cfa6d3f73
author Linux Build Service Account <lnxbuild@localhost> Thu Nov 07 17:19:32 2013 -0800
committer Gerrit - the friendly Code Review server <code-review@localhost> Thu Nov 07 17:19:32 2013 -0800
tree d2d1beffe7f15175bee7398dc3a1ac18ea9f99b1
parent a58a761ef8fd0bc1d1c3d3b66b11971ff5e708b9
parent 65872f0939f1d859a44c2887b5d25caaa0ee2903

Merge "zram: fix invalid memory access"

drivers/staging/zram/zram_drv.c

diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index 44949d2..2a85b95 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -523,7 +523,7 @@
 	return ret;
 }
 
-static void zram_reset_device(struct zram *zram)
+static void zram_reset_device(struct zram *zram, bool reset_capacity)
 {
 	size_t index;
 	struct zram_meta *meta;
@@ -552,7 +552,8 @@
 	memset(&zram->stats, 0, sizeof(zram->stats));
 
 	zram->disksize = 0;
-	set_capacity(zram->disk, 0);
+	if (reset_capacity)
+		set_capacity(zram->disk, 0);
 	up_write(&zram->init_lock);
 }
 
@@ -636,7 +637,7 @@
 	if (bdev)
 		fsync_bdev(bdev);
 
-	zram_reset_device(zram);
+	zram_reset_device(zram, true);
 	return len;
 }
 
@@ -903,10 +904,12 @@
 	for (i = 0; i < num_devices; i++) {
 		zram = &zram_devices[i];
 
-		get_disk(zram->disk);
 		destroy_device(zram);
-		zram_reset_device(zram);
-		put_disk(zram->disk);
+		/*
+		 * Shouldn't access zram->disk after destroy_device
+		 * because destroy_device already released zram->disk.
+		 */
+		zram_reset_device(zram, false);
 	}
 
 	unregister_blkdev(zram_major, "zram");