On Thu, Apr 18, 2019 at 03:17:21PM +0800, Fuqian Huang wrote:

From: Fuqian Huang huangfq.daxian@gmail.com

As there is still no hash for %p to print the address in linux 4.14, the address of function idt77252_init will be printed to syslog. Outputting kernel addresses will reveal the locations of kernel code and data. This case is similar to CVE-2018-7273[1].

Also, there is no need to print the address of function idt77252_init in idt77252_init. Just remove the print statement.

[1] https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-7273

Cc: Stable@vger.kernel.org # v4.14+ Signed-off-by: Fuqian Huang huangfq.daxian@gmail.com

---

drivers/atm/idt77252.c | 2 -- 1 file changed, 2 deletions(-)

diff --git a/drivers/atm/idt77252.c b/drivers/atm/idt77252.c index 47f3c4a..76e7736 100644 --- a/drivers/atm/idt77252.c +++ b/drivers/atm/idt77252.c @@ -3743,8 +3743,6 @@ static int __init idt77252_init(void) { struct sk_buff *skb;

• printk("%s: at %p\n", __func__, idt77252_init);

If you look at commit ad67b74d2469 ("printk: hash addresses printed with %p"), I think you missed about 14000 other instances you need to fix up :)

I suggest, if you really care about this issue in your 4.14-based kernel tree, that you just backport these pointer printk patches and be done with it. That's too big of a change to accept into the 4.14.y LTS kernel, but as the lifespan for 4.14.y running on a "general purpose" system is probably only a few more months at most, I would recomment just using 4.19.y instead as this isn't an issue at all there.

thanks,

greg k-h