[kernel-hardening] [RFC V2 6/6] drivers: uio: un-restrict sysfs pointers for UIO

From: Tobin C. Harding
Date: Sat Sep 30 2017 - 20:07:42 EST


The address and size on the UIO devices are required by userspace to
function properly. Let's un-restrict these by adding the 'P' modifier
to %pa.

Signed-off-by: Tobin C. Harding <me@xxxxxxxx>
---
drivers/uio/uio.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index ff04b7f..728ec8f 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -56,12 +56,12 @@ static ssize_t map_name_show(struct uio_mem *mem, char *buf)

static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
{
- return sprintf(buf, "%pa\n", &mem->addr);
+ return sprintf(buf, "%paP\n", &mem->addr);
}

static ssize_t map_size_show(struct uio_mem *mem, char *buf)
{
- return sprintf(buf, "%pa\n", &mem->size);
+ return sprintf(buf, "%paP\n", &mem->size);
}

static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
--
2.7.4