devcgroup: skip superfluous checks when found the DEV_ALL elem
While walking through the whitelist, if the DEV_ALL item is found, no more
check is needed.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 5fda7df..b8186ba 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -490,7 +490,7 @@
list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) {
if (wh->type & DEV_ALL)
- goto acc_check;
+ goto found;
if ((wh->type & DEV_BLOCK) && !S_ISBLK(inode->i_mode))
continue;
if ((wh->type & DEV_CHAR) && !S_ISCHR(inode->i_mode))
@@ -499,11 +499,12 @@
continue;
if (wh->minor != ~0 && wh->minor != iminor(inode))
continue;
-acc_check:
+
if ((mask & MAY_WRITE) && !(wh->access & ACC_WRITE))
continue;
if ((mask & MAY_READ) && !(wh->access & ACC_READ))
continue;
+found:
rcu_read_unlock();
return 0;
}
@@ -527,7 +528,7 @@
list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) {
if (wh->type & DEV_ALL)
- goto acc_check;
+ goto found;
if ((wh->type & DEV_BLOCK) && !S_ISBLK(mode))
continue;
if ((wh->type & DEV_CHAR) && !S_ISCHR(mode))
@@ -536,9 +537,10 @@
continue;
if (wh->minor != ~0 && wh->minor != MINOR(dev))
continue;
-acc_check:
+
if (!(wh->access & ACC_MKNOD))
continue;
+found:
rcu_read_unlock();
return 0;
}