This is a note to let you know that I've just added the patch titled zram: fix invalid memory access to the 3.11-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: zram-fix-invalid-memory-access.patch and it can be found in the queue-3.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 2b86ab9cc29fcd435cde9378c3b9ffe8b5c76128 Mon Sep 17 00:00:00 2001 From: Minchan Kim <minchan@xxxxxxxxxx> Date: Mon, 12 Aug 2013 15:13:55 +0900 Subject: zram: fix invalid memory access From: Minchan Kim <minchan@xxxxxxxxxx> commit 2b86ab9cc29fcd435cde9378c3b9ffe8b5c76128 upstream. [1] tried to fix invalid memory access on zram->disk but it didn't fix properly because get_disk failed during module exit path. Actually, we don't need to reset zram->disk's capacity to zero in module exit path so that this patch introduces new argument "reset_capacity" on zram_reset_divice and it only reset it when reset_store is called. [1] 6030ea9b, zram: avoid invalid memory access in zram_exit() Cc: Nitin Gupta <ngupta@xxxxxxxxxx> Cc: Jiang Liu <jiang.liu@xxxxxxxxxx> Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/zram/zram_drv.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -522,7 +522,7 @@ static int zram_bvec_rw(struct zram *zra 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; @@ -551,7 +551,8 @@ static void zram_reset_device(struct zra 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); } @@ -635,7 +636,7 @@ static ssize_t reset_store(struct device if (bdev) fsync_bdev(bdev); - zram_reset_device(zram); + zram_reset_device(zram, true); return len; } @@ -902,10 +903,12 @@ static void __exit zram_exit(void) 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"); Patches currently in stable-queue which might be from minchan@xxxxxxxxxx are queue-3.11/zram-fix-invalid-memory-access.patch queue-3.11/zram-don-t-grab-mutex-in-zram_slot_free_noity.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html