aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorSerge E. Hallyn <serge@hallyn.com>2011-03-23 16:43:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-23 19:47:08 -0700
commitb0e77598f87107001a00b8a4ece9c95e4254ccc4 (patch)
tree2738276570e4faa7c92a64521c192f04dca93801 /kernel
parentb515498f5bb5f38fc0e390b4ff7d00b6077de127 (diff)
downloadlinaro-lsk-b0e77598f87107001a00b8a4ece9c95e4254ccc4.tar.gz
userns: user namespaces: convert several capable() calls
CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(), because the resource comes from current's own ipc namespace. setuid/setgid are to uids in own namespace, so again checks can be against current_user_ns(). Changelog: Jan 11: Use task_ns_capable() in place of sched_capable(). Jan 11: Use nsown_capable() as suggested by Bastian Blank. Jan 11: Clarify (hopefully) some logic in futex and sched.c Feb 15: use ns_capable for ipc, not nsown_capable Feb 23: let copy_ipcs handle setting ipc_ns->user_ns Feb 23: pass ns down rather than taking it from current [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/futex.c11
-rw-r--r--kernel/futex_compat.c11
-rw-r--r--kernel/groups.c2
-rw-r--r--kernel/nsproxy.c7
-rw-r--r--kernel/sched.c9
-rw-r--r--kernel/uid16.c2
6 files changed, 29 insertions, 13 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index bda41571538..6570c459f31 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2418,10 +2418,19 @@ SYSCALL_DEFINE3(get_robust_list, int, pid,
goto err_unlock;
ret = -EPERM;
pcred = __task_cred(p);
+ /* If victim is in different user_ns, then uids are not
+ comparable, so we must have CAP_SYS_PTRACE */
+ if (cred->user->user_ns != pcred->user->user_ns) {
+ if (!ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
+ goto err_unlock;
+ goto ok;
+ }
+ /* If victim is in same user_ns, then uids are comparable */
if (cred->euid != pcred->euid &&
cred->euid != pcred->uid &&
- !capable(CAP_SYS_PTRACE))
+ !ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
goto err_unlock;
+ok:
head = p->robust_list;
rcu_read_unlock();
}
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index a7934ac75e5..5f9e689dc8f 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -153,10 +153,19 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr,
goto err_unlock;
ret = -EPERM;
pcred = __task_cred(p);
+ /* If victim is in different user_ns, then uids are not
+ comparable, so we must have CAP_SYS_PTRACE */
+ if (cred->user->user_ns != pcred->user->user_ns) {
+ if (!ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
+ goto err_unlock;
+ goto ok;
+ }
+ /* If victim is in same user_ns, then uids are comparable */
if (cred->euid != pcred->euid &&
cred->euid != pcred->uid &&
- !capable(CAP_SYS_PTRACE))
+ !ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
goto err_unlock;
+ok:
head = p->compat_robust_list;
rcu_read_unlock();
}
diff --git a/kernel/groups.c b/kernel/groups.c
index 253dc0f35cf..1cc476d52dd 100644
--- a/kernel/groups.c
+++ b/kernel/groups.c
@@ -233,7 +233,7 @@ SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist)
struct group_info *group_info;
int retval;
- if (!capable(CAP_SETGID))
+ if (!nsown_capable(CAP_SETGID))
return -EPERM;
if ((unsigned)gidsetsize > NGROUPS_MAX)
return -EINVAL;
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index ac8a56e90bf..a05d191ffdd 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -75,16 +75,11 @@ static struct nsproxy *create_new_namespaces(unsigned long flags,
goto out_uts;
}
- new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns);
+ new_nsp->ipc_ns = copy_ipcs(flags, tsk);
if (IS_ERR(new_nsp->ipc_ns)) {
err = PTR_ERR(new_nsp->ipc_ns);
goto out_ipc;
}
- if (new_nsp->ipc_ns != tsk->nsproxy->ipc_ns) {
- put_user_ns(new_nsp->ipc_ns->user_ns);
- new_nsp->ipc_ns->user_ns = task_cred_xxx(tsk, user)->user_ns;
- get_user_ns(new_nsp->ipc_ns->user_ns);
- }
new_nsp->pid_ns = copy_pid_ns(flags, task_active_pid_ns(tsk));
if (IS_ERR(new_nsp->pid_ns)) {
diff --git a/kernel/sched.c b/kernel/sched.c
index a172494a9a6..480adeb63f8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4892,8 +4892,11 @@ static bool check_same_owner(struct task_struct *p)
rcu_read_lock();
pcred = __task_cred(p);
- match = (cred->euid == pcred->euid ||
- cred->euid == pcred->uid);
+ if (cred->user->user_ns == pcred->user->user_ns)
+ match = (cred->euid == pcred->euid ||
+ cred->euid == pcred->uid);
+ else
+ match = false;
rcu_read_unlock();
return match;
}
@@ -5221,7 +5224,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
goto out_free_cpus_allowed;
}
retval = -EPERM;
- if (!check_same_owner(p) && !capable(CAP_SYS_NICE))
+ if (!check_same_owner(p) && !task_ns_capable(p, CAP_SYS_NICE))
goto out_unlock;
retval = security_task_setscheduler(p);
diff --git a/kernel/uid16.c b/kernel/uid16.c
index 419209893d8..51c6e89e861 100644
--- a/kernel/uid16.c
+++ b/kernel/uid16.c
@@ -189,7 +189,7 @@ SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
struct group_info *group_info;
int retval;
- if (!capable(CAP_SETGID))
+ if (!nsown_capable(CAP_SETGID))
return -EPERM;
if ((unsigned)gidsetsize > NGROUPS_MAX)
return -EINVAL;