[PATCH] 2.5.41 capget fix

Chris Wright
2002-10-10T00:17:37Z

Linus,

Daniel Jacobowitz noticed that sys_capget is not behaving properly when
called with pid of 0. It is supposed to return current capabilities,
not those of swapper. Also cleaned up some duplicate code from a merge
error. Patch is tested, please apply.

thanks,
-chris

--- 2.5.41/kernel/capability.c Sun Sep 15 12:19:29 2002
+++ 2.5.41-capget/kernel/capability.c Wed Oct 9 16:31:10 2002
@@ -33,7 +33,7 @@
int ret = 0;
pid_t pid;
__u32 version;
- task_t *target;
+ task_t *target = current;
struct __user_cap_data_struct data;

if (get_user(version, &header->version))
@@ -52,21 +52,20 @@
return -EINVAL;

spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);

- target = find_task_by_pid(pid);
- if (!target) {
- ret = -ESRCH;
- goto out;
+ if (pid && pid != current->pid) {
+ read_lock(&tasklist_lock);
+ target = find_task_by_pid(pid);
+ read_unlock(&tasklist_lock);
+ if (!target) {
+ ret = -ESRCH;
+ goto out;
+ }
}

- data.permitted = cap_t(target->cap_permitted);
- data.inheritable = cap_t(target->cap_inheritable);
- data.effective = cap_t(target->cap_effective);
ret = security_ops->capget(target, &data.effective, &data.inheritable, &data.permitted);

out:
- read_unlock(&tasklist_lock);
spin_unlock(&task_capability_lock);

if (!ret && copy_to_user(dataptr, &data, sizeof data))
--
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