Re: [PATCH v2 1/1] tty: add TIOCGPTPEER ioctl

2017-06-02 Thread Arnd Bergmann
On Fri, Jun 2, 2017 at 10:48 AM, Aleksa Sarai wrote: > When opening the slave end of a PTY, it is not possible for userspace to > safely ensure that /dev/pts/$num is actually a slave (in cases where the > mount namespace in which devpts was mounted is controlled by an > untrusted

Re: [PATCH v2 1/1] tty: add TIOCGPTPEER ioctl

2017-06-02 Thread Arnd Bergmann
On Fri, Jun 2, 2017 at 10:48 AM, Aleksa Sarai wrote: > When opening the slave end of a PTY, it is not possible for userspace to > safely ensure that /dev/pts/$num is actually a slave (in cases where the > mount namespace in which devpts was mounted is controlled by an > untrusted process). In

[PATCH v2 1/1] tty: add TIOCGPTPEER ioctl

2017-06-02 Thread Aleksa Sarai
When opening the slave end of a PTY, it is not possible for userspace to safely ensure that /dev/pts/$num is actually a slave (in cases where the mount namespace in which devpts was mounted is controlled by an untrusted process). In addition, there are several unresolvable race conditions if

[PATCH v2 1/1] tty: add TIOCGPTPEER ioctl

2017-06-02 Thread Aleksa Sarai
When opening the slave end of a PTY, it is not possible for userspace to safely ensure that /dev/pts/$num is actually a slave (in cases where the mount namespace in which devpts was mounted is controlled by an untrusted process). In addition, there are several unresolvable race conditions if