From: Dan Carpenter dan.carpenter@oracle.com
commit 110080cea0d0e4dfdb0b536e7f8a5633ead6a781 upstream.
There are a couple potential integer overflows here.
round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE);
The first thing is that the "m->size + (...)" addition could overflow, and the second is that round_up() overflows to zero if the result is within PAGE_SIZE of the type max.
In this code, the "m->size" variable is an u64 but we're saving the result in "map_size" which is an unsigned long and genwqe_user_vmap() takes an unsigned long as well. So I have used ULONG_MAX as the upper bound. From a practical perspective unsigned long is fine/better than trying to change all the types to u64.
Fixes: eaf4722d4645 ("GenWQE Character device and DDCB queue") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/misc/genwqe/card_dev.c | 2 ++ drivers/misc/genwqe/card_utils.c | 4 ++++ 2 files changed, 6 insertions(+)
--- a/drivers/misc/genwqe/card_dev.c +++ b/drivers/misc/genwqe/card_dev.c @@ -782,6 +782,8 @@ static int genwqe_pin_mem(struct genwqe_
if ((m->addr == 0x0) || (m->size == 0)) return -EINVAL; + if (m->size > ULONG_MAX - PAGE_SIZE - (m->addr & ~PAGE_MASK)) + return -EINVAL;
map_addr = (m->addr & PAGE_MASK); map_size = round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE); --- a/drivers/misc/genwqe/card_utils.c +++ b/drivers/misc/genwqe/card_utils.c @@ -582,6 +582,10 @@ int genwqe_user_vmap(struct genwqe_dev * /* determine space needed for page_list. */ data = (unsigned long)uaddr; offs = offset_in_page(data); + if (size > ULONG_MAX - PAGE_SIZE - offs) { + m->size = 0; /* mark unused and not added */ + return -EINVAL; + } m->nr_pages = DIV_ROUND_UP(offs + size, PAGE_SIZE);
m->page_list = kcalloc(m->nr_pages,