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-rw-r--r--kernel/auditsc.c42
-rw-r--r--kernel/capability.c78
-rw-r--r--kernel/cred-internals.h21
-rw-r--r--kernel/cred.c321
-rw-r--r--kernel/exit.c9
-rw-r--r--kernel/fork.c7
-rw-r--r--kernel/kmod.c30
-rw-r--r--kernel/ptrace.c9
-rw-r--r--kernel/signal.c10
-rw-r--r--kernel/sys.c450
-rw-r--r--kernel/user.c37
-rw-r--r--kernel/user_namespace.c12
12 files changed, 652 insertions, 374 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index ae8ef88..bc1e2d8 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2546,18 +2546,17 @@ int __audit_signal_info(int sig, struct task_struct *t)
/**
* __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
- * @bprm pointer to the bprm being processed
- * @caps the caps read from the disk
+ * @bprm: pointer to the bprm being processed
+ * @new: the proposed new credentials
+ * @old: the old credentials
*
* Simply check if the proc already has the caps given by the file and if not
* store the priv escalation info for later auditing at the end of the syscall
*
- * this can fail and we don't care. See the note in audit.h for
- * audit_log_bprm_fcaps() for my explaination....
- *
* -Eric
*/
-void __audit_log_bprm_fcaps(struct linux_binprm *bprm, kernel_cap_t *pP, kernel_cap_t *pE)
+int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
+ const struct cred *new, const struct cred *old)
{
struct audit_aux_data_bprm_fcaps *ax;
struct audit_context *context = current->audit_context;
@@ -2566,7 +2565,7 @@ void __audit_log_bprm_fcaps(struct linux_binprm *bprm, kernel_cap_t *pP, kernel_
ax = kmalloc(sizeof(*ax), GFP_KERNEL);
if (!ax)
- return;
+ return -ENOMEM;
ax->d.type = AUDIT_BPRM_FCAPS;
ax->d.next = context->aux;
@@ -2581,26 +2580,27 @@ void __audit_log_bprm_fcaps(struct linux_binprm *bprm, kernel_cap_t *pP, kernel_
ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
- ax->old_pcap.permitted = *pP;
- ax->old_pcap.inheritable = current->cred->cap_inheritable;
- ax->old_pcap.effective = *pE;
+ ax->old_pcap.permitted = old->cap_permitted;
+ ax->old_pcap.inheritable = old->cap_inheritable;
+ ax->old_pcap.effective = old->cap_effective;
- ax->new_pcap.permitted = current->cred->cap_permitted;
- ax->new_pcap.inheritable = current->cred->cap_inheritable;
- ax->new_pcap.effective = current->cred->cap_effective;
+ ax->new_pcap.permitted = new->cap_permitted;
+ ax->new_pcap.inheritable = new->cap_inheritable;
+ ax->new_pcap.effective = new->cap_effective;
+ return 0;
}
/**
* __audit_log_capset - store information about the arguments to the capset syscall
- * @pid target pid of the capset call
- * @eff effective cap set
- * @inh inheritible cap set
- * @perm permited cap set
+ * @pid: target pid of the capset call
+ * @new: the new credentials
+ * @old: the old (current) credentials
*
* Record the aguments userspace sent to sys_capset for later printing by the
* audit system if applicable
*/
-int __audit_log_capset(pid_t pid, kernel_cap_t *eff, kernel_cap_t *inh, kernel_cap_t *perm)
+int __audit_log_capset(pid_t pid,
+ const struct cred *new, const struct cred *old)
{
struct audit_aux_data_capset *ax;
struct audit_context *context = current->audit_context;
@@ -2617,9 +2617,9 @@ int __audit_log_capset(pid_t pid, kernel_cap_t *eff, kernel_cap_t *inh, kernel_c
context->aux = (void *)ax;
ax->pid = pid;
- ax->cap.effective = *eff;
- ax->cap.inheritable = *eff;
- ax->cap.permitted = *perm;
+ ax->cap.effective = new->cap_effective;
+ ax->cap.inheritable = new->cap_effective;
+ ax->cap.permitted = new->cap_permitted;
return 0;
}
diff --git a/kernel/capability.c b/kernel/capability.c
index a404b98..36b4b4d 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -15,12 +15,7 @@
#include <linux/syscalls.h>
#include <linux/pid_namespace.h>
#include <asm/uaccess.h>
-
-/*
- * This lock protects task->cap_* for all tasks including current.
- * Locking rule: acquire this prior to tasklist_lock.
- */
-static DEFINE_SPINLOCK(task_capability_lock);
+#include "cred-internals.h"
/*
* Leveraged for setting/resetting capabilities
@@ -128,12 +123,11 @@ static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
}
/*
- * If we have configured with filesystem capability support, then the
- * only thing that can change the capabilities of the current process
- * is the current process. As such, we can't be in this code at the
- * same time as we are in the process of setting capabilities in this
- * process. The net result is that we can limit our use of locks to
- * when we are reading the caps of another process.
+ * The only thing that can change the capabilities of the current
+ * process is the current process. As such, we can't be in this code
+ * at the same time as we are in the process of setting capabilities
+ * in this process. The net result is that we can limit our use of
+ * locks to when we are reading the caps of another process.
*/
static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
kernel_cap_t *pIp, kernel_cap_t *pPp)
@@ -143,7 +137,6 @@ 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;
- spin_lock(&task_capability_lock);
read_lock(&tasklist_lock);
target = find_task_by_vpid(pid);
@@ -153,34 +146,12 @@ 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);
- spin_unlock(&task_capability_lock);
} else
ret = security_capget(current, pEp, pIp, pPp);
return ret;
}
-/*
- * Atomically modify the effective capabilities returning the original
- * value. No permission check is performed here - it is assumed that the
- * caller is permitted to set the desired effective capabilities.
- */
-kernel_cap_t cap_set_effective(const kernel_cap_t pE_new)
-{
- kernel_cap_t pE_old;
-
- spin_lock(&task_capability_lock);
-
- pE_old = current->cred->cap_effective;
- current->cred->cap_effective = pE_new;
-
- spin_unlock(&task_capability_lock);
-
- return pE_old;
-}
-
-EXPORT_SYMBOL(cap_set_effective);
-
/**
* sys_capget - get the capabilities of a given process.
* @header: pointer to struct that contains capability version and
@@ -208,7 +179,6 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
return -EINVAL;
ret = cap_get_target_pid(pid, &pE, &pI, &pP);
-
if (!ret) {
struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
unsigned i;
@@ -270,6 +240,7 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
unsigned i, tocopy;
kernel_cap_t inheritable, permitted, effective;
+ struct cred *new;
int ret;
pid_t pid;
@@ -284,8 +255,8 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
if (pid != 0 && pid != task_pid_vnr(current))
return -EPERM;
- if (copy_from_user(&kdata, data, tocopy
- * sizeof(struct __user_cap_data_struct)))
+ if (copy_from_user(&kdata, data,
+ tocopy * sizeof(struct __user_cap_data_struct)))
return -EFAULT;
for (i = 0; i < tocopy; i++) {
@@ -300,24 +271,23 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
i++;
}
- ret = audit_log_capset(pid, &effective, &inheritable, &permitted);
- if (ret)
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ ret = security_capset(new, current_cred(),
+ &effective, &inheritable, &permitted);
+ if (ret < 0)
+ goto error;
+
+ ret = audit_log_capset(pid, new, current_cred());
+ if (ret < 0)
return ret;
- /* This lock is required even when filesystem capability support is
- * configured - it protects the sys_capget() call from returning
- * incorrect data in the case that the targeted process is not the
- * current one.
- */
- spin_lock(&task_capability_lock);
-
- ret = security_capset_check(&effective, &inheritable, &permitted);
- /* Having verified that the proposed changes are legal, we now put them
- * into effect.
- */
- if (!ret)
- security_capset_set(&effective, &inheritable, &permitted);
- spin_unlock(&task_capability_lock);
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
return ret;
}
diff --git a/kernel/cred-internals.h b/kernel/cred-internals.h
new file mode 100644
index 0000000..2dc4fc2
--- /dev/null
+++ b/kernel/cred-internals.h
@@ -0,0 +1,21 @@
+/* Internal credentials stuff
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+/*
+ * user.c
+ */
+static inline void sched_switch_user(struct task_struct *p)
+{
+#ifdef CONFIG_USER_SCHED
+ sched_move_task(p);
+#endif /* CONFIG_USER_SCHED */
+}
+
diff --git a/kernel/cred.c b/kernel/cred.c
index ac73e36..cb6b5ed 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -15,6 +15,10 @@
#include <linux/keyctl.h>
#include <linux/init_task.h>
#include <linux/security.h>
+#include <linux/cn_proc.h>
+#include "cred-internals.h"
+
+static struct kmem_cache *cred_jar;
/*
* The common credentials for the initial task's thread group
@@ -64,7 +68,7 @@ static void release_tgcred_rcu(struct rcu_head *rcu)
/*
* Release a set of thread group credentials.
*/
-static void release_tgcred(struct cred *cred)
+void release_tgcred(struct cred *cred)
{
#ifdef CONFIG_KEYS
struct thread_group_cred *tgcred = cred->tgcred;
@@ -81,79 +85,322 @@ static void put_cred_rcu(struct rcu_head *rcu)
{
struct cred *cred = container_of(rcu, struct cred, rcu);
- BUG_ON(atomic_read(&cred->usage) != 0);
+ if (atomic_read(&cred->usage) != 0)
+ panic("CRED: put_cred_rcu() sees %p with usage %d\n",
+ cred, atomic_read(&cred->usage));
+ security_cred_free(cred);
key_put(cred->thread_keyring);
key_put(cred->request_key_auth);
release_tgcred(cred);
put_group_info(cred->group_info);
free_uid(cred->user);
- security_cred_free(cred);
- kfree(cred);
+ kmem_cache_free(cred_jar, cred);
}
/**
* __put_cred - Destroy a set of credentials
- * @sec: The record to release
+ * @cred: The record to release
*
* Destroy a set of credentials on which no references remain.
*/
void __put_cred(struct cred *cred)
{
+ BUG_ON(atomic_read(&cred->usage) != 0);
+
call_rcu(&cred->rcu, put_cred_rcu);
}
EXPORT_SYMBOL(__put_cred);
+/**
+ * prepare_creds - Prepare a new set of credentials for modification
+ *
+ * Prepare a new set of task credentials for modification. A task's creds
+ * shouldn't generally be modified directly, therefore this function is used to
+ * prepare a new copy, which the caller then modifies and then commits by
+ * calling commit_creds().
+ *
+ * Returns a pointer to the new creds-to-be if successful, NULL otherwise.
+ *
+ * Call commit_creds() or abort_creds() to clean up.
+ */
+struct cred *prepare_creds(void)
+{
+ struct task_struct *task = current;
+ const struct cred *old;
+ struct cred *new;
+
+ BUG_ON(atomic_read(&task->cred->usage) < 1);
+
+ new = kmem_cache_alloc(cred_jar, GFP_KERNEL);
+ if (!new)
+ return NULL;
+
+ old = task->cred;
+ memcpy(new, old, sizeof(struct cred));
+
+ atomic_set(&new->usage, 1);
+ get_group_info(new->group_info);
+ get_uid(new->user);
+
+#ifdef CONFIG_KEYS
+ key_get(new->thread_keyring);
+ key_get(new->request_key_auth);
+ atomic_inc(&new->tgcred->usage);
+#endif
+
+#ifdef CONFIG_SECURITY
+ new->security = NULL;
+#endif
+
+ if (security_prepare_creds(new, old, GFP_KERNEL) < 0)
+ goto error;
+ return new;
+
+error:
+ abort_creds(new);
+ return NULL;
+}
+EXPORT_SYMBOL(prepare_creds);
+
+/*
+ * prepare new credentials for the usermode helper dispatcher
+ */
+struct cred *prepare_usermodehelper_creds(void)
+{
+#ifdef CONFIG_KEYS
+ struct thread_group_cred *tgcred = NULL;
+#endif
+ struct cred *new;
+
+#ifdef CONFIG_KEYS
+ tgcred = kzalloc(sizeof(*new->tgcred), GFP_ATOMIC);
+ if (!tgcred)
+ return NULL;
+#endif
+
+ new = kmem_cache_alloc(cred_jar, GFP_ATOMIC);
+ if (!new)
+ return NULL;
+
+ memcpy(new, &init_cred, sizeof(struct cred));
+
+ atomic_set(&new->usage, 1);
+ get_group_info(new->group_info);
+ get_uid(new->user);
+
+#ifdef CONFIG_KEYS
+ new->thread_keyring = NULL;
+ new->request_key_auth = NULL;
+ new->jit_keyring = KEY_REQKEY_DEFL_DEFAULT;
+
+ atomic_set(&tgcred->usage, 1);
+ spin_lock_init(&tgcred->lock);
+ new->tgcred = tgcred;
+#endif
+
+#ifdef CONFIG_SECURITY
+ new->security = NULL;
+#endif
+ if (security_prepare_creds(new, &init_cred, GFP_ATOMIC) < 0)
+ goto error;
+
+ BUG_ON(atomic_read(&new->usage) != 1);
+ return new;
+
+error:
+ put_cred(new);
+ return NULL;
+}
+
/*
* Copy credentials for the new process created by fork()
+ *
+ * We share if we can, but under some circumstances we have to generate a new
+ * set.
*/
int copy_creds(struct task_struct *p, unsigned long clone_flags)
{
- struct cred *pcred;
- int ret;
+#ifdef CONFIG_KEYS
+ struct thread_group_cred *tgcred;
+#endif
+ struct cred *new;
+
+ mutex_init(&p->cred_exec_mutex);
- pcred = kmemdup(p->cred, sizeof(*p->cred), GFP_KERNEL);
- if (!pcred)
+ if (
+#ifdef CONFIG_KEYS
+ !p->cred->thread_keyring &&
+#endif
+ clone_flags & CLONE_THREAD
+ ) {
+ get_cred(p->cred);
+ atomic_inc(&p->cred->user->processes);
+ return 0;
+ }
+
+ new = prepare_creds();
+ if (!new)
return -ENOMEM;
#ifdef CONFIG_KEYS
- if (clone_flags & CLONE_THREAD) {
- atomic_inc(&pcred->tgcred->usage);
- } else {
- pcred->tgcred = kmalloc(sizeof(struct cred), GFP_KERNEL);
- if (!pcred->tgcred) {
- kfree(pcred);
+ /* new threads get their own thread keyrings if their parent already
+ * had one */
+ if (new->thread_keyring) {
+ key_put(new->thread_keyring);
+ new->thread_keyring = NULL;
+ if (clone_flags & CLONE_THREAD)
+ install_thread_keyring_to_cred(new);
+ }
+
+ /* we share the process and session keyrings between all the threads in
+ * a process - this is slightly icky as we violate COW credentials a
+ * bit */
+ if (!(clone_flags & CLONE_THREAD)) {
+ tgcred = kmalloc(sizeof(*tgcred), GFP_KERNEL);
+ if (!tgcred) {
+ put_cred(new);
return -ENOMEM;
}
- atomic_set(&pcred->tgcred->usage, 1);
- spin_lock_init(&pcred->tgcred->lock);
- pcred->tgcred->process_keyring = NULL;
- pcred->tgcred->session_keyring =
- key_get(p->cred->tgcred->session_keyring);
+ atomic_set(&tgcred->usage, 1);
+ spin_lock_init(&tgcred->lock);
+ tgcred->process_keyring = NULL;
+ tgcred->session_keyring = key_get(new->tgcred->session_keyring);
+
+ release_tgcred(new);
+ new->tgcred = tgcred;
}
#endif
-#ifdef CONFIG_SECURITY
- pcred->security = NULL;
-#endif
+ atomic_inc(&new->user->processes);
+ p->cred = new;
+ return 0;
+}
- ret = security_cred_alloc(pcred);
- if (ret < 0) {
- release_tgcred(pcred);
- kfree(pcred);
- return ret;
+/**
+ * commit_creds - Install new credentials upon the current task
+ * @new: The credentials to be assigned
+ *
+ * Install a new set of credentials to the current task, using RCU to replace
+ * the old set.
+ *
+ * This function eats the caller's reference to the new credentials.
+ *
+ * Always returns 0 thus allowing this function to be tail-called at the end
+ * of, say, sys_setgid().
+ */
+int commit_creds(struct cred *new)
+{
+ struct task_struct *task = current;
+ const struct cred *old;
+
+ BUG_ON(atomic_read(&new->usage) < 1);
+ BUG_ON(atomic_read(&task->cred->usage) < 1);
+
+ old = task->cred;
+ security_commit_creds(new, old);
+
+ /* dumpability changes */
+ if (old->euid != new->euid ||
+ old->egid != new->egid ||
+ old->fsuid != new->fsuid ||
+ old->fsgid != new->fsgid ||
+ !cap_issubset(new->cap_permitted, old->cap_permitted)) {
+ set_dumpable(task->mm, suid_dumpable);
+ task->pdeath_signal = 0;
+ smp_wmb();
}
- atomic_set(&pcred->usage, 1);
- get_group_info(pcred->group_info);
- get_uid(pcred->user);
- key_get(pcred->thread_keyring);
- key_get(pcred->request_key_auth);
+ /* alter the thread keyring */
+ if (new->fsuid != old->fsuid)
+ key_fsuid_changed(task);
+ if (new->fsgid != old->fsgid)
+ key_fsgid_changed(task);
+
+ /* do it
+ * - What if a process setreuid()'s and this brings the
+ * new uid over his NPROC rlimit? We can check this now
+ * cheaply with the new uid cache, so if it matters
+ * we should be checking for it. -DaveM
+ */
+ if (new->user != old->user)
+ atomic_inc(&new->user->processes);
+ rcu_assign_pointer(task->cred, new);
+ if (new->user != old->user)
+ atomic_dec(&old->user->processes);
+
+ sched_switch_user(task);
+
+ /* send notifications */
+ if (new->uid != old->uid ||
+ new->euid != old->euid ||
+ new->suid != old->suid ||
+ new->fsuid != old->fsuid)
+ proc_id_connector(task, PROC_EVENT_UID);
- atomic_inc(&pcred->user->processes);
+ if (new->gid != old->gid ||
+ new->egid != old->egid ||
+ new->sgid != old->sgid ||
+ new->fsgid != old->fsgid)
+ proc_id_connector(task, PROC_EVENT_GID);
- /* RCU assignment is unneeded here as no-one can have accessed this
- * pointer yet, barring us */
- p->cred = pcred;
+ put_cred(old);
return 0;
}
+EXPORT_SYMBOL(commit_creds);
+
+/**
+ * abort_creds - Discard a set of credentials and unlock the current task
+ * @new: The credentials that were going to be applied
+ *
+ * Discard a set of credentials that were under construction and unlock the
+ * current task.
+ */
+void abort_creds(struct cred *new)
+{
+ BUG_ON(atomic_read(&new->usage) < 1);
+ put_cred(new);
+}
+EXPORT_SYMBOL(abort_creds);
+
+/**
+ * override_creds - Temporarily override the current process's credentials
+ * @new: The credentials to be assigned
+ *
+ * Install a set of temporary override credentials on the current process,
+ * returning the old set for later reversion.
+ */
+const struct cred *override_creds(const struct cred *new)
+{
+ const struct cred *old = current->cred;
+
+ rcu_assign_pointer(current->cred, get_cred(new));
+ return old;
+}
+EXPORT_SYMBOL(override_creds);
+
+/**
+ * revert_creds - Revert a temporary credentials override
+ * @old: The credentials to be restored
+ *
+ * Revert a temporary set of override credentials to an old set, discarding the
+ * override set.
+ */
+void revert_creds(const struct cred *old)
+{
+ const struct cred *override = current->cred;
+
+ rcu_assign_pointer(current->cred, old);
+ put_cred(override);
+}
+EXPORT_SYMBOL(revert_creds);
+
+/*
+ * initialise the credentials stuff
+ */
+void __init cred_init(void)
+{
+ /* allocate a slab in which we can store credentials */
+ cred_jar = kmem_cache_create("cred_jar", sizeof(struct cred),
+ 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+}
diff --git a/kernel/exit.c b/kernel/exit.c
index bbc2253..c0711da 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -47,12 +47,14 @@
#include <linux/blkdev.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/tracehook.h>
+#include <linux/init_task.h>
#include <trace/sched.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
+#include "cred-internals.h"
static void exit_mm(struct task_struct * tsk);
@@ -338,12 +340,12 @@ static void reparent_to_kthreadd(void)
/* cpus_allowed? */
/* rt_priority? */
/* signals? */
- security_task_reparent_to_init(current);
memcpy(current->signal->rlim, init_task.signal->rlim,
sizeof(current->signal->rlim));
- atomic_inc(&(INIT_USER->__count));
+
+ atomic_inc(&init_cred.usage);
+ commit_creds(&init_cred);
write_unlock_irq(&tasklist_lock);
- switch_uid(INIT_USER);
}
void __set_special_pids(struct pid *pid)
@@ -1085,7 +1087,6 @@ NORET_TYPE void do_exit(long code)
check_stack_usage();
exit_thread();
cgroup_exit(tsk, 1);
- exit_keys(tsk);
if (group_dead && tsk->signal->leader)
disassociate_ctty(1);
diff --git a/kernel/fork.c b/kernel/fork.c
index ded1972..82a7948 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1084,10 +1084,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
goto bad_fork_cleanup_sighand;
if ((retval = copy_mm(clone_flags, p)))
goto bad_fork_cleanup_signal;
- if ((retval = copy_keys(clone_flags, p)))
- goto bad_fork_cleanup_mm;
if ((retval = copy_namespaces(clone_flags, p)))
- goto bad_fork_cleanup_keys;
+ goto bad_fork_cleanup_mm;
if ((retval = copy_io(clone_flags, p)))
goto bad_fork_cleanup_namespaces;
retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
@@ -1252,8 +1250,6 @@ bad_fork_cleanup_io:
put_io_context(p->io_context);
bad_fork_cleanup_namespaces:
exit_task_namespaces(p);
-bad_fork_cleanup_keys:
- exit_keys(p);
bad_fork_cleanup_mm:
if (p->mm)
mmput(p->mm);
@@ -1281,6 +1277,7 @@ bad_fork_cleanup_cgroup:
bad_fork_cleanup_put_domain:
module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
+ atomic_dec(&p->cred->user->processes);
put_cred(p->cred);
bad_fork_free:
free_task(p);
diff --git a/kernel/kmod.c b/kernel/kmod.c
index f044f8f..b46dbb9 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -118,10 +118,10 @@ EXPORT_SYMBOL(request_module);
struct subprocess_info {
struct work_struct work;
struct completion *complete;
+ struct cred *cred;
char *path;
char **argv;
char **envp;
- struct key *ring;
enum umh_wait wait;
int retval;
struct file *stdin;
@@ -134,19 +134,20 @@ struct subprocess_info {
static int ____call_usermodehelper(void *data)
{
struct subprocess_info *sub_info = data;
- struct key *new_session, *old_session;
int retval;
- /* Unblock all signals and set the session keyring. */
- new_session = key_get(sub_info->ring);
+ BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
+ /* Unblock all signals */
spin_lock_irq(&current->sighand->siglock);
- old_session = __install_session_keyring(new_session);
flush_signal_handlers(current, 1);
sigemptyset(&current->blocked);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- key_put(old_session);
+ /* Install the credentials */
+ commit_creds(sub_info->cred);
+ sub_info->cred = NULL;
/* Install input pipe when needed */
if (sub_info->stdin) {
@@ -185,6 +186,8 @@ void call_usermodehelper_freeinfo(struct subprocess_info *info)
{
if (info->cleanup)
(*info->cleanup)(info->argv, info->envp);
+ if (info->cred)
+ put_cred(info->cred);
kfree(info);
}
EXPORT_SYMBOL(call_usermodehelper_freeinfo);
@@ -240,6 +243,8 @@ static void __call_usermodehelper(struct work_struct *work)
pid_t pid;
enum umh_wait wait = sub_info->wait;
+ BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
/* CLONE_VFORK: wait until the usermode helper has execve'd
* successfully We need the data structures to stay around
* until that is done. */
@@ -362,6 +367,9 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
sub_info->path = path;
sub_info->argv = argv;
sub_info->envp = envp;
+ sub_info->cred = prepare_usermodehelper_creds();
+ if (!sub_info->cred)
+ return NULL;
out:
return sub_info;
@@ -376,7 +384,13 @@ EXPORT_SYMBOL(call_usermodehelper_setup);
void call_usermodehelper_setkeys(struct subprocess_info *info,
struct key *session_keyring)
{
- info->ring = session_keyring;
+#ifdef CONFIG_KEYS
+ struct thread_group_cred *tgcred = info->cred->tgcred;
+ key_put(tgcred->session_keyring);
+ tgcred->session_keyring = key_get(session_keyring);
+#else
+ BUG();
+#endif
}
EXPORT_SYMBOL(call_usermodehelper_setkeys);
@@ -444,6 +458,8 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
DECLARE_COMPLETION_ONSTACK(done);
int retval = 0;
+ BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+
helper_lock();
if (sub_info->path[0] == '\0')
goto out;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index b9d5f4e..f764b88 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -171,6 +171,14 @@ int ptrace_attach(struct task_struct *task)
if (same_thread_group(task, current))
goto out;
+ /* Protect exec's credential calculations against our interference;
+ * SUID, SGID and LSM creds get determined differently under ptrace.
+ */
+ retval = mutex_lock_interruptible(&current->cred_exec_mutex);
+ if (retval < 0)
+ goto out;
+
+ retval = -EPERM;
repeat:
/*
* Nasty, nasty.
@@ -210,6 +218,7 @@ repeat:
bad:
write_unlock_irqrestore(&tasklist_lock, flags);
task_unlock(task);
+ mutex_unlock(&current->cred_exec_mutex);
out:
return retval;
}
diff --git a/kernel/signal.c b/kernel/signal.c
index 8498912..2a64304 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -180,7 +180,7 @@ int next_signal(struct sigpending *pending, sigset_t *mask)
/*
* allocate a new signal queue record
* - this may be called without locks if and only if t == current, otherwise an
- * appopriate lock must be held to protect t's user_struct
+ * appopriate lock must be held to stop the target task from exiting
*/
static struct sigqueue *__sigqueue_alloc(struct task_struct *t, gfp_t flags,
int override_rlimit)
@@ -194,7 +194,7 @@ static struct sigqueue *__sigqueue_alloc(struct task_struct *t, gfp_t flags,
* caller must be holding the RCU readlock (by way of a spinlock) and
* we use RCU protection here
*/
- user = __task_cred(t)->user;
+ user = get_uid(__task_cred(t)->user);
atomic_inc(&user->sigpending);
if (override_rlimit ||
atomic_read(&user->sigpending) <=
@@ -202,12 +202,14 @@ static struct sigqueue *__sigqueue_alloc(struct task_struct *t, gfp_t flags,
q = kmem_cache_alloc(sigqueue_cachep, flags);
if (unlikely(q == NULL)) {
atomic_dec(&user->sigpending);
+ free_uid(user);
} else {
INIT_LIST_HEAD(&q->list);
q->flags = 0;
- q->user = get_uid(user);
+ q->user = user;
}
- return(q);
+
+ return q;
}
static void __sigqueue_free(struct sigqueue *q)
diff --git a/kernel/sys.c b/kernel/sys.c
index ccc9eb7..ab73504 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -180,7 +180,7 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
} while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
break;
case PRIO_USER:
- user = cred->user;
+ user = (struct user_struct *) cred->user;
if (!who)
who = cred->uid;
else if ((who != cred->uid) &&
@@ -479,47 +479,48 @@ void ctrl_alt_del(void)
*/
asmlinkage long sys_setregid(gid_t rgid, gid_t egid)
{
- struct cred *cred = current->cred;
- int old_rgid = cred->gid;
- int old_egid = cred->egid;
- int new_rgid = old_rgid;
- int new_egid = old_egid;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
if (retval)
- return retval;
+ goto error;
+ retval = -EPERM;
if (rgid != (gid_t) -1) {
- if ((old_rgid == rgid) ||
- (cred->egid == rgid) ||
+ if (old->gid == rgid ||
+ old->egid == rgid ||
capable(CAP_SETGID))
- new_rgid = rgid;
+ new->gid = rgid;
else
- return -EPERM;
+ goto error;
}
if (egid != (gid_t) -1) {
- if ((old_rgid == egid) ||
- (cred->egid == egid) ||
- (cred->sgid == egid) ||
+ if (old->gid == egid ||
+ old->egid == egid ||
+ old->sgid == egid ||
capable(CAP_SETGID))
- new_egid = egid;
+ new->egid = egid;
else
- return -EPERM;
- }
- if (new_egid != old_egid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
+ goto error;
}
+
if (rgid != (gid_t) -1 ||
- (egid != (gid_t) -1 && egid != old_rgid))
- cred->sgid = new_egid;
- cred->fsgid = new_egid;
- cred->egid = new_egid;
- cred->gid = new_rgid;
- key_fsgid_changed(current);
- proc_id_connector(current, PROC_EVENT_GID);
- return 0;
+ (egid != (gid_t) -1 && egid != old->gid))
+ new->sgid = new->egid;
+ new->fsgid = new->egid;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
}
/*
@@ -529,40 +530,42 @@ asmlinkage long sys_setregid(gid_t rgid, gid_t egid)
*/
asmlinkage long sys_setgid(gid_t gid)
{
- struct cred *cred = current->cred;
- int old_egid = cred->egid;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
if (retval)
- return retval;
+ goto error;
- if (capable(CAP_SETGID)) {
- if (old_egid != gid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- cred->gid = cred->egid = cred->sgid = cred->fsgid = gid;
- } else if ((gid == cred->gid) || (gid == cred->sgid)) {
- if (old_egid != gid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- cred->egid = cred->fsgid = gid;
- }
+ retval = -EPERM;
+ if (capable(CAP_SETGID))
+ new->gid = new->egid = new->sgid = new->fsgid = gid;
+ else if (gid == old->gid || gid == old->sgid)
+ new->egid = new->fsgid = gid;
else
- return -EPERM;
+ goto error;
- key_fsgid_changed(current);
- proc_id_connector(current, PROC_EVENT_GID);
- return 0;
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
}
-static int set_user(uid_t new_ruid, int dumpclear)
+/*
+ * change the user struct in a credentials set to match the new UID
+ */
+static int set_user(struct cred *new)
{
struct user_struct *new_user;
- new_user = alloc_uid(current->nsproxy->user_ns, new_ruid);
+ new_user = alloc_uid(current->nsproxy->user_ns, new->uid);
if (!new_user)
return -EAGAIN;
@@ -573,13 +576,8 @@ static int set_user(uid_t new_ruid, int dumpclear)
return -EAGAIN;
}
- switch_uid(new_user);
-
- if (dumpclear) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- current->cred->uid = new_ruid;
+ free_uid(new->user);
+ new->user = new_user;
return 0;
}
@@ -600,55 +598,56 @@ static int set_user(uid_t new_ruid, int dumpclear)
*/
asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
{
- struct cred *cred = current->cred;
- int old_ruid, old_euid, old_suid, new_ruid, new_euid;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
if (retval)
- return retval;
-
- new_ruid = old_ruid = cred->uid;
- new_euid = old_euid = cred->euid;
- old_suid = cred->suid;
+ goto error;
+ retval = -EPERM;
if (ruid != (uid_t) -1) {
- new_ruid = ruid;
- if ((old_ruid != ruid) &&
- (cred->euid != ruid) &&
+ new->uid = ruid;
+ if (old->uid != ruid &&
+ old->euid != ruid &&
!capable(CAP_SETUID))
- return -EPERM;
+ goto error;
}
if (euid != (uid_t) -1) {
- new_euid = euid;
- if ((old_ruid != euid) &&
- (cred->euid != euid) &&
- (cred->suid != euid) &&
+ new->euid = euid;
+ if (old->uid != euid &&
+ old->euid != euid &&
+ old->suid != euid &&
!capable(CAP_SETUID))
- return -EPERM;
+ goto error;
}
- if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0)
- return -EAGAIN;
+ retval = -EAGAIN;
+ if (new->uid != old->uid && set_user(new) < 0)
+ goto error;
- if (new_euid != old_euid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- cred->fsuid = cred->euid = new_euid;
if (ruid != (uid_t) -1 ||
- (euid != (uid_t) -1 && euid != old_ruid))
- cred->suid = cred->euid;
- cred->fsuid = cred->euid;
-
- key_fsuid_changed(current);
- proc_id_connector(current, PROC_EVENT_UID);
+ (euid != (uid_t) -1 && euid != old->uid))
+ new->suid = new->euid;
+ new->fsuid = new->euid;
- return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE);
-}
+ retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
+ if (retval < 0)
+ goto error;
+ return commit_creds(new);
+error:
+ abort_creds(new);
+ return retval;
+}
/*
* setuid() is implemented like SysV with SAVED_IDS
@@ -663,37 +662,41 @@ asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
*/
asmlinkage long sys_setuid(uid_t uid)
{
- struct cred *cred = current->cred;
- int old_euid = cred->euid;
- int old_ruid, old_suid, new_suid;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
if (retval)
- return retval;
+ goto error;
- old_ruid = cred->uid;
- old_suid = cred->suid;
- new_suid = old_suid;
-
+ retval = -EPERM;
if (capable(CAP_SETUID)) {
- if (uid != old_ruid && set_user(uid, old_euid != uid) < 0)
- return -EAGAIN;
- new_suid = uid;
- } else if ((uid != cred->uid) && (uid != new_suid))
- return -EPERM;
-
- if (old_euid != uid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
+ new->suid = new->uid = uid;
+ if (uid != old->uid && set_user(new) < 0) {
+ retval = -EAGAIN;
+ goto error;
+ }
+ } else if (uid != old->uid && uid != new->suid) {
+ goto error;
}
- cred->fsuid = cred->euid = uid;
- cred->suid = new_suid;
- key_fsuid_changed(current);
- proc_id_connector(current, PROC_EVENT_UID);
+ new->fsuid = new->euid = uid;
+
+ retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
+ if (retval < 0)
+ goto error;
+
+ return commit_creds(new);
- return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID);
+error:
+ abort_creds(new);
+ return retval;
}
@@ -703,47 +706,53 @@ asmlinkage long sys_setuid(uid_t uid)
*/
asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
{
- struct cred *cred = current->cred;
- int old_ruid = cred->uid;
- int old_euid = cred->euid;
- int old_suid = cred->suid;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
if (retval)
- return retval;
+ goto error;
+ old = current_cred();
+ retval = -EPERM;
if (!capable(CAP_SETUID)) {
- if ((ruid != (uid_t) -1) && (ruid != cred->uid) &&
- (ruid != cred->euid) && (ruid != cred->suid))
- return -EPERM;
- if ((euid != (uid_t) -1) && (euid != cred->uid) &&
- (euid != cred->euid) && (euid != cred->suid))
- return -EPERM;
- if ((suid != (uid_t) -1) && (suid != cred->uid) &&
- (suid != cred->euid) && (suid != cred->suid))
- return -EPERM;
+ if (ruid != (uid_t) -1 && ruid != old->uid &&
+ ruid != old->euid && ruid != old->suid)
+ goto error;
+ if (euid != (uid_t) -1 && euid != old->uid &&
+ euid != old->euid && euid != old->suid)
+ goto error;
+ if (suid != (uid_t) -1 && suid != old->uid &&
+ suid != old->euid && suid != old->suid)
+ goto error;
}
+
+ retval = -EAGAIN;
if (ruid != (uid_t) -1) {
- if (ruid != cred->uid &&
- set_user(ruid, euid != cred->euid) < 0)
- return -EAGAIN;
+ new->uid = ruid;
+ if (ruid != old->uid && set_user(new) < 0)
+ goto error;
}
- if (euid != (uid_t) -1) {
- if (euid != cred->euid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- cred->euid = euid;
- }
- cred->fsuid = cred->euid;
+ if (euid != (uid_t) -1)
+ new->euid = euid;
if (suid != (uid_t) -1)
- cred->suid = suid;
+ new->suid = suid;
+ new->fsuid = new->euid;
- key_fsuid_changed(current);
- proc_id_connector(current, PROC_EVENT_UID);
+ retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
+ if (retval < 0)
+ goto error;
- return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES);
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
}
asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid)
@@ -763,40 +772,45 @@ asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __us
*/
asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
{
- struct cred *cred = current->cred;
+ const struct cred *old;
+ struct cred *new;
int retval;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
if (retval)
- return retval;
+ goto error;
+ retval = -EPERM;
if (!capable(CAP_SETGID)) {
- if ((rgid != (gid_t) -1) && (rgid != cred->gid) &&
- (rgid != cred->egid) && (rgid != cred->sgid))
- return -EPERM;
- if ((egid != (gid_t) -1) && (egid != cred->gid) &&
- (egid != cred->egid) && (egid != cred->sgid))
- return -EPERM;
- if ((sgid != (gid_t) -1) && (sgid != cred->gid) &&
- (sgid != cred->egid) && (sgid != cred->sgid))
- return -EPERM;
+ if (rgid != (gid_t) -1 && rgid != old->gid &&
+ rgid != old->egid && rgid != old->sgid)
+ goto error;
+ if (egid != (gid_t) -1 && egid != old->gid &&
+ egid != old->egid && egid != old->sgid)
+ goto error;
+ if (sgid != (gid_t) -1 && sgid != old->gid &&
+ sgid != old->egid && sgid != old->sgid)
+ goto error;
}
- if (egid != (gid_t) -1) {
- if (egid != cred->egid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
- }
- cred->egid = egid;
- }
- cred->fsgid = cred->egid;
+
if (rgid != (gid_t) -1)
- cred->gid = rgid;
+ new->gid = rgid;
+ if (egid != (gid_t) -1)
+ new->egid = egid;
if (sgid != (gid_t) -1)
- cred->sgid = sgid;
+ new->sgid = sgid;
+ new->fsgid = new->egid;
- key_fsgid_changed(current);
- proc_id_connector(current, PROC_EVENT_GID);
- return 0;
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
}
asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid)
@@ -820,28 +834,35 @@ asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __us
*/
asmlinkage long sys_setfsuid(uid_t uid)
{
- struct cred *cred = current->cred;
- int old_fsuid;
+ const struct cred *old;
+ struct cred *new;
+ uid_t old_fsuid;
+
+ new = prepare_creds();
+ if (!new)
+ return current_fsuid();
+ old = current_cred();
+ old_fsuid = old->fsuid;
- old_fsuid = cred->fsuid;
- if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS))
- return old_fsuid;
+ if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0)
+ goto error;
- if (uid == cred->uid || uid == cred->euid ||
- uid == cred->suid || uid == cred->fsuid ||
+ if (uid == old->uid || uid == old->euid ||
+ uid == old->suid || uid == old->fsuid ||
capable(CAP_SETUID)) {
if (uid != old_fsuid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
+ new->fsuid = uid;
+ if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
+ goto change_okay;
}
- cred->fsuid = uid;
}
- key_fsuid_changed(current);
- proc_id_connector(current, PROC_EVENT_UID);
-
- security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS);
+error:
+ abort_creds(new);
+ return old_fsuid;
+change_okay:
+ commit_creds(new);
return old_fsuid;
}
@@ -850,24 +871,34 @@ asmlinkage long sys_setfsuid(uid_t uid)
*/
asmlinkage long sys_setfsgid(gid_t gid)
{
- struct cred *cred = current->cred;
- int old_fsgid;
+ const struct cred *old;
+ struct cred *new;
+ gid_t old_fsgid;
+
+ new = prepare_creds();
+ if (!new)
+ return current_fsgid();
+ old = current_cred();
+ old_fsgid = old->fsgid;
- old_fsgid = cred->fsgid;
if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
- return old_fsgid;
+ goto error;
- if (gid == cred->gid || gid == cred->egid ||
- gid == cred->sgid || gid == cred->fsgid ||
+ if (gid == old->gid || gid == old->egid ||
+ gid == old->sgid || gid == old->fsgid ||
capable(CAP_SETGID)) {
if (gid != old_fsgid) {
- set_dumpable(current->mm, suid_dumpable);
- smp_wmb();
+ new->fsgid = gid;
+ goto change_okay;
}
- cred->fsgid = gid;
- key_fsgid_changed(current);
- proc_id_connector(current, PROC_EVENT_GID);
}
+
+error:
+ abort_creds(new);
+ return old_fsgid;
+
+change_okay:
+ commit_creds(new);
return old_fsgid;
}
@@ -1136,7 +1167,7 @@ EXPORT_SYMBOL(groups_free);
/* export the group_info to a user-space array */
static int groups_to_user(gid_t __user *grouplist,
- struct group_info *group_info)
+ const struct group_info *group_info)
{
int i;
unsigned int count = group_info->ngroups;
@@ -1227,31 +1258,25 @@ int groups_search(const struct group_info *group_info, gid_t grp)
}
/**
- * set_groups - Change a group subscription in a security record
- * @sec: The security record to alter
- * @group_info: The group list to impose
+ * set_groups - Change a group subscription in a set of credentials
+ * @new: The newly prepared set of credentials to alter
+ * @group_info: The group list to install
*
- * Validate a group subscription and, if valid, impose it upon a task security
- * record.
+ * Validate a group subscription and, if valid, insert it into a set
+ * of credentials.
*/
-int set_groups(struct cred *cred, struct group_info *group_info)
+int set_groups(struct cred *new, struct group_info *group_info)
{
int retval;
- struct group_info *old_info;
retval = security_task_setgroups(group_info);
if (retval)
return retval;
+ put_group_info(new->group_info);
groups_sort(group_info);
get_group_info(group_info);
-
- spin_lock(&cred->lock);
- old_info = cred->group_info;
- cred->group_info = group_info;
- spin_unlock(&cred->lock);
-
- put_group_info(old_info);
+ new->group_info = group_info;
return 0;
}
@@ -1266,7 +1291,20 @@ EXPORT_SYMBOL(set_groups);
*/
int set_current_groups(struct group_info *group_info)
{
- return set_groups(current->cred, group_info);
+ struct cred *new;
+ int ret;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ ret = set_groups(new, group_info);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret;
+ }
+
+ return commit_creds(new);
}
EXPORT_SYMBOL(set_current_groups);
@@ -1666,9 +1704,11 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
unsigned char comm[sizeof(me->comm)];
long error;
- if (security_task_prctl(option, arg2, arg3, arg4, arg5, &error))
+ error = security_task_prctl(option, arg2, arg3, arg4, arg5);
+ if (error != -ENOSYS)
return error;
+ error = 0;
switch (option) {
case PR_SET_PDEATHSIG:
if (!valid_signal(arg2)) {
diff --git a/kernel/user.c b/kernel/user.c
index 104d22a..d476307 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -16,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/user_namespace.h>
+#include "cred-internals.h"
struct user_namespace init_user_ns = {
.kref = {
@@ -104,16 +105,10 @@ static int sched_create_user(struct user_struct *up)
return rc;
}
-static void sched_switch_user(struct task_struct *p)
-{
- sched_move_task(p);
-}
-
#else /* CONFIG_USER_SCHED */
static void sched_destroy_user(struct user_struct *up) { }
static int sched_create_user(struct user_struct *up) { return 0; }
-static void sched_switch_user(struct task_struct *p) { }
#endif /* CONFIG_USER_SCHED */
@@ -448,36 +443,6 @@ out_unlock:
return NULL;
}
-void switch_uid(struct user_struct *new_user)
-{
- struct user_struct *old_user;
-
- /* What if a process setreuid()'s and this brings the
- * new uid over his NPROC rlimit? We can check this now
- * cheaply with the new uid cache, so if it matters
- * we should be checking for it. -DaveM
- */
- old_user = current->cred->user;
- atomic_inc(&new_user->processes);
- atomic_dec(&old_user->processes);
- switch_uid_keyring(new_user);
- current->cred->user = new_user;
- sched_switch_user(current);
-
- /*
- * We need to synchronize with __sigqueue_alloc()
- * doing a get_uid(p->user).. If that saw the old
- * user value, we need to wait until it has exited
- * its critical region before we can free the old
- * structure.
- */
- smp_mb();
- spin_unlock_wait(&current->sighand->siglock);
-
- free_uid(old_user);
- suid_keys(current);
-}
-
#ifdef CONFIG_USER_NS
void release_uids(struct user_namespace *ns)
{
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index f82730a..0d9c51d 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -19,6 +19,7 @@ static struct user_namespace *clone_user_ns(struct user_namespace *old_ns)
{
struct user_namespace *ns;
struct user_struct *new_user;
+ struct cred *new;
int n;
ns = kmalloc(sizeof(struct user_namespace), GFP_KERNEL);
@@ -45,7 +46,16 @@ static struct user_namespace *clone_user_ns(struct user_namespace *old_ns)
return ERR_PTR(-ENOMEM);
}
- switch_uid(new_user);
+ /* Install the new user */
+ new = prepare_creds();
+ if (!new) {
+ free_uid(new_user);
+ free_uid(ns->root_user);
+ kfree(ns);
+ }
+ free_uid(new->user);
+ new->user = new_user;
+ commit_creds(new);
return ns;
}
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