zram: pass down the bvec we need to read into in the work struct
authorJérôme Glisse <jglisse@redhat.com>
Fri, 26 Apr 2019 05:23:41 +0000 (22:23 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 26 Apr 2019 16:18:05 +0000 (09:18 -0700)
commite153abc0739ff77bd89c9ba1688cdb963464af97
tree87f8fcbdd0fda1970e0dffd7b1a10edfee6df158
parent89c02e69fc5245f8a2f34b58b42d43a737af1a5e
zram: pass down the bvec we need to read into in the work struct

When scheduling work item to read page we need to pass down the proper
bvec struct which points to the page to read into.  Before this patch it
uses a randomly initialized bvec (only if PAGE_SIZE != 4096) which is
wrong.

Note that without this patch on arch/kernel where PAGE_SIZE != 4096
userspace could read random memory through a zram block device (thought
userspace probably would have no control on the address being read).

Link: http://lkml.kernel.org/r/20190408183219.26377-1-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/block/zram/zram_drv.c