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-rw-r--r--kernel/cgroup/cgroup-internal.h19
-rw-r--r--kernel/cgroup/cgroup-v1.c33
-rw-r--r--kernel/cgroup/cgroup.c88
-rw-r--r--kernel/entry/common.c4
-rw-r--r--kernel/entry/kvm.c4
-rw-r--r--kernel/events/core.c4
-rw-r--r--kernel/kcsan/Makefile1
-rw-r--r--kernel/notifier.c15
-rw-r--r--kernel/sched/core.c2
-rw-r--r--kernel/trace/trace.c6
10 files changed, 118 insertions, 58 deletions
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index bfbeabc17a9d..6e36e854b512 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -65,6 +65,25 @@ static inline struct cgroup_fs_context *cgroup_fc2context(struct fs_context *fc)
return container_of(kfc, struct cgroup_fs_context, kfc);
}
+struct cgroup_pidlist;
+
+struct cgroup_file_ctx {
+ struct cgroup_namespace *ns;
+
+ struct {
+ void *trigger;
+ } psi;
+
+ struct {
+ bool started;
+ struct css_task_iter iter;
+ } procs;
+
+ struct {
+ struct cgroup_pidlist *pidlist;
+ } procs1;
+};
+
/*
* A cgroup can be associated with multiple css_sets as different tasks may
* belong to different cgroups on different hierarchies. In the other
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 81c9e0685948..41e0837a5a0b 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -394,6 +394,7 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
* next pid to display, if any
*/
struct kernfs_open_file *of = s->private;
+ struct cgroup_file_ctx *ctx = of->priv;
struct cgroup *cgrp = seq_css(s)->cgroup;
struct cgroup_pidlist *l;
enum cgroup_filetype type = seq_cft(s)->private;
@@ -403,25 +404,24 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
mutex_lock(&cgrp->pidlist_mutex);
/*
- * !NULL @of->priv indicates that this isn't the first start()
- * after open. If the matching pidlist is around, we can use that.
- * Look for it. Note that @of->priv can't be used directly. It
- * could already have been destroyed.
+ * !NULL @ctx->procs1.pidlist indicates that this isn't the first
+ * start() after open. If the matching pidlist is around, we can use
+ * that. Look for it. Note that @ctx->procs1.pidlist can't be used
+ * directly. It could already have been destroyed.
*/
- if (of->priv)
- of->priv = cgroup_pidlist_find(cgrp, type);
+ if (ctx->procs1.pidlist)
+ ctx->procs1.pidlist = cgroup_pidlist_find(cgrp, type);
/*
* Either this is the first start() after open or the matching
* pidlist has been destroyed inbetween. Create a new one.
*/
- if (!of->priv) {
- ret = pidlist_array_load(cgrp, type,
- (struct cgroup_pidlist **)&of->priv);
+ if (!ctx->procs1.pidlist) {
+ ret = pidlist_array_load(cgrp, type, &ctx->procs1.pidlist);
if (ret)
return ERR_PTR(ret);
}
- l = of->priv;
+ l = ctx->procs1.pidlist;
if (pid) {
int end = l->length;
@@ -449,7 +449,8 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
static void cgroup_pidlist_stop(struct seq_file *s, void *v)
{
struct kernfs_open_file *of = s->private;
- struct cgroup_pidlist *l = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct cgroup_pidlist *l = ctx->procs1.pidlist;
if (l)
mod_delayed_work(cgroup_pidlist_destroy_wq, &l->destroy_dwork,
@@ -460,7 +461,8 @@ static void cgroup_pidlist_stop(struct seq_file *s, void *v)
static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
{
struct kernfs_open_file *of = s->private;
- struct cgroup_pidlist *l = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct cgroup_pidlist *l = ctx->procs1.pidlist;
pid_t *p = v;
pid_t *end = l->list + l->length;
/*
@@ -504,10 +506,11 @@ static ssize_t __cgroup1_procs_write(struct kernfs_open_file *of,
goto out_unlock;
/*
- * Even if we're attaching all tasks in the thread group, we only
- * need to check permissions on one of them.
+ * Even if we're attaching all tasks in the thread group, we only need
+ * to check permissions on one of them. Check permissions using the
+ * credentials from file open to protect against inherited fd attacks.
*/
- cred = current_cred();
+ cred = of->file->f_cred;
tcred = get_task_cred(task);
if (!uid_eq(cred->euid, GLOBAL_ROOT_UID) &&
!uid_eq(cred->euid, tcred->uid) &&
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 919194de39c8..cafb8c114a21 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -3630,6 +3630,7 @@ static int cgroup_cpu_pressure_show(struct seq_file *seq, void *v)
static ssize_t cgroup_pressure_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, enum psi_res res)
{
+ struct cgroup_file_ctx *ctx = of->priv;
struct psi_trigger *new;
struct cgroup *cgrp;
struct psi_group *psi;
@@ -3648,7 +3649,7 @@ static ssize_t cgroup_pressure_write(struct kernfs_open_file *of, char *buf,
return PTR_ERR(new);
}
- psi_trigger_replace(&of->priv, new);
+ psi_trigger_replace(&ctx->psi.trigger, new);
cgroup_put(cgrp);
@@ -3679,12 +3680,16 @@ static ssize_t cgroup_cpu_pressure_write(struct kernfs_open_file *of,
static __poll_t cgroup_pressure_poll(struct kernfs_open_file *of,
poll_table *pt)
{
- return psi_trigger_poll(&of->priv, of->file, pt);
+ struct cgroup_file_ctx *ctx = of->priv;
+
+ return psi_trigger_poll(&ctx->psi.trigger, of->file, pt);
}
static void cgroup_pressure_release(struct kernfs_open_file *of)
{
- psi_trigger_replace(&of->priv, NULL);
+ struct cgroup_file_ctx *ctx = of->priv;
+
+ psi_trigger_replace(&ctx->psi.trigger, NULL);
}
bool cgroup_psi_enabled(void)
@@ -3811,24 +3816,43 @@ static ssize_t cgroup_kill_write(struct kernfs_open_file *of, char *buf,
static int cgroup_file_open(struct kernfs_open_file *of)
{
struct cftype *cft = of_cft(of);
+ struct cgroup_file_ctx *ctx;
+ int ret;
- if (cft->open)
- return cft->open(of);
- return 0;
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->ns = current->nsproxy->cgroup_ns;
+ get_cgroup_ns(ctx->ns);
+ of->priv = ctx;
+
+ if (!cft->open)
+ return 0;
+
+ ret = cft->open(of);
+ if (ret) {
+ put_cgroup_ns(ctx->ns);
+ kfree(ctx);
+ }
+ return ret;
}
static void cgroup_file_release(struct kernfs_open_file *of)
{
struct cftype *cft = of_cft(of);
+ struct cgroup_file_ctx *ctx = of->priv;
if (cft->release)
cft->release(of);
+ put_cgroup_ns(ctx->ns);
+ kfree(ctx);
}
static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, loff_t off)
{
- struct cgroup_namespace *ns = current->nsproxy->cgroup_ns;
+ struct cgroup_file_ctx *ctx = of->priv;
struct cgroup *cgrp = of->kn->parent->priv;
struct cftype *cft = of_cft(of);
struct cgroup_subsys_state *css;
@@ -3845,7 +3869,7 @@ static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf,
*/
if ((cgrp->root->flags & CGRP_ROOT_NS_DELEGATE) &&
!(cft->flags & CFTYPE_NS_DELEGATABLE) &&
- ns != &init_cgroup_ns && ns->root_cset->dfl_cgrp == cgrp)
+ ctx->ns != &init_cgroup_ns && ctx->ns->root_cset->dfl_cgrp == cgrp)
return -EPERM;
if (cft->write)
@@ -4751,21 +4775,21 @@ void css_task_iter_end(struct css_task_iter *it)
static void cgroup_procs_release(struct kernfs_open_file *of)
{
- if (of->priv) {
- css_task_iter_end(of->priv);
- kfree(of->priv);
- }
+ struct cgroup_file_ctx *ctx = of->priv;
+
+ if (ctx->procs.started)
+ css_task_iter_end(&ctx->procs.iter);
}
static void *cgroup_procs_next(struct seq_file *s, void *v, loff_t *pos)
{
struct kernfs_open_file *of = s->private;
- struct css_task_iter *it = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
if (pos)
(*pos)++;
- return css_task_iter_next(it);
+ return css_task_iter_next(&ctx->procs.iter);
}
static void *__cgroup_procs_start(struct seq_file *s, loff_t *pos,
@@ -4773,21 +4797,18 @@ static void *__cgroup_procs_start(struct seq_file *s, loff_t *pos,
{
struct kernfs_open_file *of = s->private;
struct cgroup *cgrp = seq_css(s)->cgroup;
- struct css_task_iter *it = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct css_task_iter *it = &ctx->procs.iter;
/*
* When a seq_file is seeked, it's always traversed sequentially
* from position 0, so we can simply keep iterating on !0 *pos.
*/
- if (!it) {
+ if (!ctx->procs.started) {
if (WARN_ON_ONCE((*pos)))
return ERR_PTR(-EINVAL);
-
- it = kzalloc(sizeof(*it), GFP_KERNEL);
- if (!it)
- return ERR_PTR(-ENOMEM);
- of->priv = it;
css_task_iter_start(&cgrp->self, iter_flags, it);
+ ctx->procs.started = true;
} else if (!(*pos)) {
css_task_iter_end(it);
css_task_iter_start(&cgrp->self, iter_flags, it);
@@ -4838,9 +4859,9 @@ static int cgroup_may_write(const struct cgroup *cgrp, struct super_block *sb)
static int cgroup_procs_write_permission(struct cgroup *src_cgrp,
struct cgroup *dst_cgrp,
- struct super_block *sb)
+ struct super_block *sb,
+ struct cgroup_namespace *ns)
{
- struct cgroup_namespace *ns = current->nsproxy->cgroup_ns;
struct cgroup *com_cgrp = src_cgrp;
int ret;
@@ -4869,11 +4890,12 @@ static int cgroup_procs_write_permission(struct cgroup *src_cgrp,
static int cgroup_attach_permissions(struct cgroup *src_cgrp,
struct cgroup *dst_cgrp,
- struct super_block *sb, bool threadgroup)
+ struct super_block *sb, bool threadgroup,
+ struct cgroup_namespace *ns)
{
int ret = 0;
- ret = cgroup_procs_write_permission(src_cgrp, dst_cgrp, sb);
+ ret = cgroup_procs_write_permission(src_cgrp, dst_cgrp, sb, ns);
if (ret)
return ret;
@@ -4890,8 +4912,10 @@ static int cgroup_attach_permissions(struct cgroup *src_cgrp,
static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf,
bool threadgroup)
{
+ struct cgroup_file_ctx *ctx = of->priv;
struct cgroup *src_cgrp, *dst_cgrp;
struct task_struct *task;
+ const struct cred *saved_cred;
ssize_t ret;
bool locked;
@@ -4909,9 +4933,16 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf,
src_cgrp = task_cgroup_from_root(task, &cgrp_dfl_root);
spin_unlock_irq(&css_set_lock);
- /* process and thread migrations follow same delegation rule */
+ /*
+ * Process and thread migrations follow same delegation rule. Check
+ * permissions using the credentials from file open to protect against
+ * inherited fd attacks.
+ */
+ saved_cred = override_creds(of->file->f_cred);
ret = cgroup_attach_permissions(src_cgrp, dst_cgrp,
- of->file->f_path.dentry->d_sb, threadgroup);
+ of->file->f_path.dentry->d_sb,
+ threadgroup, ctx->ns);
+ revert_creds(saved_cred);
if (ret)
goto out_finish;
@@ -6130,7 +6161,8 @@ static int cgroup_css_set_fork(struct kernel_clone_args *kargs)
goto err;
ret = cgroup_attach_permissions(cset->dfl_cgrp, dst_cgrp, sb,
- !(kargs->flags & CLONE_THREAD));
+ !(kargs->flags & CLONE_THREAD),
+ current->nsproxy->cgroup_ns);
if (ret)
goto err;
diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index d5a61d565ad5..bad713684c2e 100644
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -187,7 +187,7 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
/* Check if any of the above work has queued a deferred wakeup */
tick_nohz_user_enter_prepare();
- ti_work = READ_ONCE(current_thread_info()->flags);
+ ti_work = read_thread_flags();
}
/* Return the latest work state for arch_exit_to_user_mode() */
@@ -196,7 +196,7 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
static void exit_to_user_mode_prepare(struct pt_regs *regs)
{
- unsigned long ti_work = READ_ONCE(current_thread_info()->flags);
+ unsigned long ti_work = read_thread_flags();
lockdep_assert_irqs_disabled();
diff --git a/kernel/entry/kvm.c b/kernel/entry/kvm.c
index 49972ee99aff..96d476e06c77 100644
--- a/kernel/entry/kvm.c
+++ b/kernel/entry/kvm.c
@@ -26,7 +26,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work)
if (ret)
return ret;
- ti_work = READ_ONCE(current_thread_info()->flags);
+ ti_work = read_thread_flags();
} while (ti_work & XFER_TO_GUEST_MODE_WORK || need_resched());
return 0;
}
@@ -43,7 +43,7 @@ int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu)
* disabled in the inner loop before going into guest mode. No need
* to disable interrupts here.
*/
- ti_work = READ_ONCE(current_thread_info()->flags);
+ ti_work = read_thread_flags();
if (!(ti_work & XFER_TO_GUEST_MODE_WORK))
return 0;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 30d94f68c5bd..1362b9b770d8 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1808,6 +1808,8 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
list_add_rcu(&event->event_entry, &ctx->event_list);
ctx->nr_events++;
+ if (event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT)
+ ctx->nr_user++;
if (event->attr.inherit_stat)
ctx->nr_stat++;
@@ -1999,6 +2001,8 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
event->attach_state &= ~PERF_ATTACH_CONTEXT;
ctx->nr_events--;
+ if (event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT)
+ ctx->nr_user--;
if (event->attr.inherit_stat)
ctx->nr_stat--;
diff --git a/kernel/kcsan/Makefile b/kernel/kcsan/Makefile
index c2bb07f5bcc7..e893b0e1d62a 100644
--- a/kernel/kcsan/Makefile
+++ b/kernel/kcsan/Makefile
@@ -8,6 +8,7 @@ CFLAGS_REMOVE_debugfs.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE)
CFLAGS_core.o := $(call cc-option,-fno-conserve-stack) \
+ $(call cc-option,-mno-outline-atomics) \
-fno-stack-protector -DDISABLE_BRANCH_PROFILING
obj-y := core.o debugfs.o report.o
diff --git a/kernel/notifier.c b/kernel/notifier.c
index b8251dc0bc0f..ba005ebf4730 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -20,12 +20,13 @@ BLOCKING_NOTIFIER_HEAD(reboot_notifier_list);
*/
static int notifier_chain_register(struct notifier_block **nl,
- struct notifier_block *n)
+ struct notifier_block *n)
{
while ((*nl) != NULL) {
if (unlikely((*nl) == n)) {
- WARN(1, "double register detected");
- return 0;
+ WARN(1, "notifier callback %ps already registered",
+ n->notifier_call);
+ return -EEXIST;
}
if (n->priority > (*nl)->priority)
break;
@@ -134,7 +135,7 @@ static int notifier_call_chain_robust(struct notifier_block **nl,
*
* Adds a notifier to an atomic notifier chain.
*
- * Currently always returns zero.
+ * Returns 0 on success, %-EEXIST on error.
*/
int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
struct notifier_block *n)
@@ -216,7 +217,7 @@ NOKPROBE_SYMBOL(atomic_notifier_call_chain);
* Adds a notifier to a blocking notifier chain.
* Must be called in process context.
*
- * Currently always returns zero.
+ * Returns 0 on success, %-EEXIST on error.
*/
int blocking_notifier_chain_register(struct blocking_notifier_head *nh,
struct notifier_block *n)
@@ -335,7 +336,7 @@ EXPORT_SYMBOL_GPL(blocking_notifier_call_chain);
* Adds a notifier to a raw notifier chain.
* All locking must be provided by the caller.
*
- * Currently always returns zero.
+ * Returns 0 on success, %-EEXIST on error.
*/
int raw_notifier_chain_register(struct raw_notifier_head *nh,
struct notifier_block *n)
@@ -406,7 +407,7 @@ EXPORT_SYMBOL_GPL(raw_notifier_call_chain);
* Adds a notifier to an SRCU notifier chain.
* Must be called in process context.
*
- * Currently always returns zero.
+ * Returns 0 on success, %-EEXIST on error.
*/
int srcu_notifier_chain_register(struct srcu_notifier_head *nh,
struct notifier_block *n)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 77563109c0ea..bb5e7fd25354 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8520,7 +8520,7 @@ void sched_show_task(struct task_struct *p)
rcu_read_unlock();
pr_cont(" stack:%5lu pid:%5d ppid:%6d flags:0x%08lx\n",
free, task_pid_nr(p), ppid,
- (unsigned long)task_thread_info(p)->flags);
+ read_task_thread_flags(p));
print_worker_info(KERN_INFO, p);
print_stop_info(KERN_INFO, p);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 88de94da596b..78ea542ce3bc 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3207,7 +3207,7 @@ struct trace_buffer_struct {
char buffer[4][TRACE_BUF_SIZE];
};
-static struct trace_buffer_struct *trace_percpu_buffer;
+static struct trace_buffer_struct __percpu *trace_percpu_buffer;
/*
* This allows for lockless recording. If we're nested too deeply, then
@@ -3217,7 +3217,7 @@ static char *get_trace_buf(void)
{
struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer);
- if (!buffer || buffer->nesting >= 4)
+ if (!trace_percpu_buffer || buffer->nesting >= 4)
return NULL;
buffer->nesting++;
@@ -3236,7 +3236,7 @@ static void put_trace_buf(void)
static int alloc_percpu_trace_buffer(void)
{
- struct trace_buffer_struct *buffers;
+ struct trace_buffer_struct __percpu *buffers;
if (trace_percpu_buffer)
return 0;