path: root/kernel/capability.c
diff options
authorThomas Gleixner <tglx@linutronix.de>2009-12-09 17:13:31 +0100
committerJames Morris <jmorris@namei.org>2009-12-10 09:42:48 +1100
commit86fc80f16e8a2449d5827bf1a9838b7fd9f70097 (patch)
tree23f4d20995f9538c6f609baa2d0bf3315f013b46 /kernel/capability.c
parent67fa4880c5e059428392ca6f7c2f9c38e8546fea (diff)
capabilities: Use RCU to protect task lookup in sys_capget
cap_get_target_pid() protects the task lookup with tasklist_lock. security_capget() is called under tasklist_lock as well but tasklist_lock does not protect anything there. The capabilities are protected by RCU already. So tasklist_lock only protects the lookup and prevents the task going away, which can be done with rcu_read_lock() as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'kernel/capability.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/capability.c b/kernel/capability.c
index 7f876e60521..9e4697e9b27 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -135,7 +135,7 @@ static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
if (pid && (pid != task_pid_vnr(current))) {
struct task_struct *target;
- read_lock(&tasklist_lock);
+ rcu_read_lock();
target = find_task_by_vpid(pid);
if (!target)
@@ -143,7 +143,7 @@ static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
ret = security_capget(target, pEp, pIp, pPp);
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
} else
ret = security_capget(current, pEp, pIp, pPp);