From: Todd Poynor <toddpoynor@xxxxxxxxxx> Use user namespace to determine whether gasket device file opener is root, allowing root access to containers, if necessary. Reported-by: Dmitry Torokhov <dtor@xxxxxxxxxxxx> Signed-off-by: Todd Poynor <toddpoynor@xxxxxxxxxx> --- drivers/staging/gasket/gasket_core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/staging/gasket/gasket_core.c b/drivers/staging/gasket/gasket_core.c index b832a4f529f27..291cd6d074a2e 100644 --- a/drivers/staging/gasket/gasket_core.c +++ b/drivers/staging/gasket/gasket_core.c @@ -13,13 +13,16 @@ #include "gasket_page_table.h" #include "gasket_sysfs.h" +#include <linux/capability.h> #include <linux/compiler.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/of.h> +#include <linux/pid_namespace.h> #include <linux/printk.h> +#include <linux/sched.h> #ifdef GASKET_KERNEL_TRACE_SUPPORT #define CREATE_TRACE_POINTS @@ -1064,7 +1067,8 @@ static int gasket_open(struct inode *inode, struct file *filp) char task_name[TASK_COMM_LEN]; struct gasket_cdev_info *dev_info = container_of(inode->i_cdev, struct gasket_cdev_info, cdev); - int is_root = capable(CAP_SYS_ADMIN); + struct pid_namespace *pid_ns = task_active_pid_ns(current); + int is_root = ns_capable(pid_ns->user_ns, CAP_SYS_ADMIN); gasket_dev = dev_info->gasket_dev_ptr; driver_desc = gasket_dev->internal_desc->driver_desc; @@ -1147,6 +1151,8 @@ static int gasket_release(struct inode *inode, struct file *file) char task_name[TASK_COMM_LEN]; struct gasket_cdev_info *dev_info = container_of(inode->i_cdev, struct gasket_cdev_info, cdev); + struct pid_namespace *pid_ns = task_active_pid_ns(current); + int is_root = ns_capable(pid_ns->user_ns, CAP_SYS_ADMIN); gasket_dev = dev_info->gasket_dev_ptr; driver_desc = gasket_dev->internal_desc->driver_desc; @@ -1158,7 +1164,7 @@ static int gasket_release(struct inode *inode, struct file *file) "Releasing device node. Call origin: tgid %u (%s) " "(f_mode: 0%03o, fmode_write: %d, is_root: %u)\n", current->tgid, task_name, file->f_mode, - (file->f_mode & FMODE_WRITE), capable(CAP_SYS_ADMIN)); + (file->f_mode & FMODE_WRITE), is_root); dev_dbg(gasket_dev->dev, "Current open count (owning tgid %u): %d\n", ownership->owner, ownership->write_open_count); -- 2.18.0.345.g5c9ce644c3-goog _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
