Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-11 14:42:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

cgroup: make cgroup_path() not print double slashes

Browse Source 
While reimplementing cgroup_path(), 65dff759d2 ("cgroup: fix
cgroup_path() vs rename() race") introduced a bug where the path of a
non-root cgroup would have two slahses at the beginning, which is
caused by treating the root cgroup which has the name '/' like
non-root cgroups.

 $ grep systemd /proc/self/cgroup
 1:name=systemd://user/root/1

Fix it by special casing root cgroup case and not looping over it in
the normal path.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
This commit is contained in:
Tejun Heo 2013-04-14 10:32:19 -07:00
parent 26d5bbe5ba
commit da1f296fd2
1 changed files with 8 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
kernel/cgroup.c
View File

@ -1811,11 +1811,17 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
int ret = -ENAMETOOLONG; int ret = -ENAMETOOLONG;
char *start; char *start;
if (!cgrp->parent) {
if (strlcpy(buf, "/", buflen) >= buflen)
return -ENAMETOOLONG;
return 0;
}
start = buf + buflen - 1; start = buf + buflen - 1;
*start = '\0'; *start = '\0';
rcu_read_lock(); rcu_read_lock();
while (cgrp) { do {
const char *name = cgroup_name(cgrp); const char *name = cgroup_name(cgrp);
int len; int len;
@ -1824,15 +1830,12 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
goto out; goto out;
memcpy(start, name, len); memcpy(start, name, len);
if (!cgrp->parent)
break;
if (--start < buf) if (--start < buf)
goto out; goto out;
*start = '/'; *start = '/';
cgrp = cgrp->parent; cgrp = cgrp->parent;
} } while (cgrp->parent);
ret = 0; ret = 0;
memmove(buf, start, buf + buflen - start); memmove(buf, start, buf + buflen - start);
out: out: