Robert Jennings 2787f959d6 zram: Return zero'd pages on new reads ... Currently zram will do nothing to the page in the bvec when that page has not been previously written. This allows random data to leak to user space. That can be seen by doing the following: ## Load the module and create a 256Mb zram device called /dev/zram0 # modprobe zram # echo $((256*1024*1024)) > /sys/class/block/zram0/disksize ## Initialize the device by writing zero to the first block # dd if=/dev/zero of=/dev/zram0 bs=512 count=1 ## Read ~256Mb of memory into a file and hope for something interesting # dd if=/dev/zram0 of=file This patch will treat an unwritten page as a zero-filled page. If a page is read before a write has occurred the data returned is all 0's. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>		2011-02-04 13:29:12 -08:00
..
Kconfig	zram/xvmalloc: create CONFIG_ZRAM_DEBUG for debug code	2011-02-04 13:29:11 -08:00
Makefile	Staging: zram: Makefile: replace the use of <module>-objs with <module>-y	2010-10-08 07:23:41 -07:00
xvmalloc.c	zram/xvmalloc: create CONFIG_ZRAM_DEBUG for debug code	2011-02-04 13:29:11 -08:00
xvmalloc.h
xvmalloc_int.h	zram/xvmalloc: Close 32byte hole on 64bit CPUs	2011-02-04 13:29:11 -08:00
zram.txt	Staging: zram: Update zram documentation	2010-08-31 15:36:36 -07:00
zram_drv.c	zram: Return zero'd pages on new reads	2011-02-04 13:29:12 -08:00
zram_drv.h	zram: Prevent overflow in logical block size	2011-02-04 13:29:11 -08:00
zram_sysfs.c	Staging: zram: round up the disk size provided by user	2011-01-20 16:06:18 -08:00