ACPR/android_system_core
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

libprocessgroup: Fix cgroup directory ownership setup

Browse source 
When cgroup directory is created its user and ownership gets set, however
because previous code was storing getpwnam() return value the second
invocation would effectively override the previous ones result. Fix this
by copying necessary results. Also change getpwnam() to getgrnam() when
group name is converted into gid. getpwnam() works because of the way
Android uses these ids, however more generally this is incorrect and
getgrnam() should be used instead.

Bug: 111307099
Test: verified user/group membership of the cgroup directories
Change-Id: I78668bc1a36a74f53d8e9825e2d06e3e09501e7a
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
This commit is contained in:
Suren Baghdasaryan 2019-02-06 13:25:29 -08:00
parent bece53e515
commit e3ad888011
1 changed files with 21 additions and 18 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

39
libprocessgroup/cgroup_map.cpp
View file

@ -19,6 +19,7 @@
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <sys/mman.h>
#include <sys/mount.h>
@ -72,26 +73,28 @@ static bool Mkdir(const std::string& path, mode_t mode, const std::string& uid,
}
}
passwd* uid_pwd = nullptr;
passwd* gid_pwd = nullptr;
if (!uid.empty()) {
uid_pwd = getpwnam(uid.c_str());
if (!uid_pwd) {
PLOG(ERROR) << "Unable to decode UID for '" << uid << "'";
return false;
}
if (!gid.empty()) {
gid_pwd = getpwnam(gid.c_str());
if (!gid_pwd) {
PLOG(ERROR) << "Unable to decode GID for '" << gid << "'";
return false;
}
}
if (uid.empty()) {
return true;
}
if (uid_pwd && lchown(path.c_str(), uid_pwd->pw_uid, gid_pwd ? gid_pwd->pw_uid : -1) < 0) {
passwd* uid_pwd = getpwnam(uid.c_str());
if (!uid_pwd) {
PLOG(ERROR) << "Unable to decode UID for '" << uid << "'";
return false;
}
uid_t pw_uid = uid_pwd->pw_uid;
gid_t gr_gid = -1;
if (!gid.empty()) {
group* gid_pwd = getgrnam(gid.c_str());
if (!gid_pwd) {
PLOG(ERROR) << "Unable to decode GID for '" << gid << "'";
return false;
}
gr_gid = gid_pwd->gr_gid;
}
if (lchown(path.c_str(), pw_uid, gr_gid) < 0) {
PLOG(ERROR) << "lchown() failed for " << path;
return false;
}