[Devel] [PATCH RHEL7 COMMIT] ve: Use ve_name() in devperms ioctl

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-123.1.2-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-123.1.2.vz7.5.22
------>
commit 812ac8c85ec65cb323c68c07050a20c7b60d806b
Author: Kirill Tkhai <ktkhai at odin.com>
Date:   Mon Jun 29 17:42:56 2015 +0400

    ve: Use ve_name() in devperms ioctl
    
    In PCS7 we use UUID instead of ctid for cgroup directories names,
    so we should open it.
    
    Below is small test program to check the patch works:
    
    #include <linux/vzcalluser.h>
    #include <stdio.h>
    #include <fcntl.h>
    
    main()
    {
            struct vzctl_setdevperms s;
            int fd = open("/dev/vzctl", O_RDWR);
            unsigned major = 182;
            unsigned minor = 281233;
            s.veid = 101;
            s.type = S_IFBLK|030;
            s.dev = (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
            s.mask = S_IXUSR;
    
            if (fd < 0) {
                    printf("open err\n");
                    return -1;
            }
    
            if (ioctl(fd, VZCTL_SETDEVPERMS, &s))
                    printf("ioctl\n");
    }
    
    https://jira.sw.ru/browse/PSBM-34497
    
    Signed-off-by: Kirill Tkhai <ktkhai at odin.com>
    Reviewed-by: Vladimir Davydov <vdavydov at parallels.com>
---
 kernel/ve/vecalls.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/kernel/ve/vecalls.c b/kernel/ve/vecalls.c
index e262c5e..be4fb1e 100644
--- a/kernel/ve/vecalls.c
+++ b/kernel/ve/vecalls.c
@@ -160,13 +160,14 @@ static int real_setdevperms(envid_t veid, unsigned type,
 		return -ESRCH;
 
 	down_read(&ve->op_sem);
-	err = -ESRCH;
 
-	cgroup = ve_cgroup_open(devices_root, 0, ve->veid);
-	err = PTR_ERR(cgroup);
-	if (IS_ERR(cgroup))
+	cgroup = cgroup_kernel_open(devices_root, 0, ve_name(ve));
+	if (IS_ERR_OR_NULL(cgroup)) {
+		err = PTR_ERR(cgroup) ? : -ESRCH;
 		goto out;
+	}
 
+	err = -EAGAIN;
 	if (ve->is_running)
 		err = devcgroup_set_perms_ve(cgroup, type, dev, mask);