wonderful-mobile/exynos-linux-stable
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

CRED: Use RCU to access another task's creds and to release a task's own creds

Browse source 
Use RCU to access another task's creds and to release a task's own creds.
This means that it will be possible for the credentials of a task to be
replaced without another task (a) requiring a full lock to read them, and (b)
seeing deallocated memory.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
David Howells 2008-11-14 10:39:19 +11:00 • committed by James Morris
parent 86a264abe5
commit c69e8d9c01
28 changed files with 353 additions and 202 deletions
Download patch file Download diff file Expand all files Collapse all files

6
kernel/tsacct.c
View file

@ -27,6 +27,7 @@
*/
void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
{
const struct cred *tcred;
struct timespec uptime, ts;
u64 ac_etime;
@ -53,10 +54,11 @@ void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
stats->ac_flag |= AXSIG;
stats->ac_nice = task_nice(tsk);
stats->ac_sched = tsk->policy;
stats->ac_uid = tsk->cred->uid;
stats->ac_gid = tsk->cred->gid;
stats->ac_pid = tsk->pid;
rcu_read_lock();
tcred = __task_cred(tsk);
stats->ac_uid = tcred->uid;
stats->ac_gid = tcred->gid;
stats->ac_ppid = pid_alive(tsk) ?
rcu_dereference(tsk->real_parent)->tgid : 0;
rcu_read_unlock();