Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Adjacent changes:

net/mptcp/protocol.h
  63740448a32e ("mptcp: fix accept vs worker race")
  2a6a870e44dd ("mptcp: stops worker on unaccepted sockets at listener close")
  ddb1a072f858 ("mptcp: move first subflow allocation at mpc access time")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

7 files changed, 216 insertions, 68 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d6db6de3e9ea..6e12cc296ad8 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3243,6 +3243,21 @@ static int backtrack_insn(struct bpf_verifier_env *env, int idx,
 			}
 		} else if (opcode == BPF_EXIT) {
 			return -ENOTSUPP;
+		} else if (BPF_SRC(insn->code) == BPF_X) {
+			if (!(*reg_mask & (dreg | sreg)))
+				return 0;
+			/* dreg <cond> sreg
+			 * Both dreg and sreg need precision before
+			 * this insn. If only sreg was marked precise
+			 * before it would be equally necessary to
+			 * propagate it to dreg.
+			 */
+			*reg_mask |= (sreg | dreg);
+			 /* else dreg <cond> K
+			  * Only dreg still needs precision before
+			  * this insn, so for the K-based conditional
+			  * there is nothing new to be marked.
+			  */
 		}
 	} else if (class == BPF_LD) {
 		if (!(*reg_mask & dreg))
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 636f1c682ac0..505d86b16642 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1513,7 +1513,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd,
 	spin_unlock_irq(&callback_lock);
 
 	if (adding || deleting)
-		update_tasks_cpumask(parent, tmp->new_cpus);
+		update_tasks_cpumask(parent, tmp->addmask);
 
 	/*
 	 * Set or clear CS_SCHED_LOAD_BALANCE when partcmd_update, if necessary.
@@ -1770,10 +1770,13 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 	/*
 	 * Use the cpumasks in trialcs for tmpmasks when they are pointers
 	 * to allocated cpumasks.
+	 *
+	 * Note that update_parent_subparts_cpumask() uses only addmask &
+	 * delmask, but not new_cpus.
 	 */
 	tmp.addmask  = trialcs->subparts_cpus;
 	tmp.delmask  = trialcs->effective_cpus;
-	tmp.new_cpus = trialcs->cpus_allowed;
+	tmp.new_cpus = NULL;
 #endif
 
 	retval = validate_change(cs, trialcs);
@@ -1838,6 +1841,11 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 	}
 	spin_unlock_irq(&callback_lock);
 
+#ifdef CONFIG_CPUMASK_OFFSTACK
+	/* Now trialcs->cpus_allowed is available */
+	tmp.new_cpus = trialcs->cpus_allowed;
+#endif
+
 	/* effective_cpus will be updated here */
 	update_cpumasks_hier(cs, &tmp, false);
 
@@ -2445,6 +2453,20 @@ static int fmeter_getrate(struct fmeter *fmp)
 
 static struct cpuset *cpuset_attach_old_cs;
 
+/*
+ * Check to see if a cpuset can accept a new task
+ * For v1, cpus_allowed and mems_allowed can't be empty.
+ * For v2, effective_cpus can't be empty.
+ * Note that in v1, effective_cpus = cpus_allowed.
+ */
+static int cpuset_can_attach_check(struct cpuset *cs)
+{
+	if (cpumask_empty(cs->effective_cpus) ||
+	   (!is_in_v2_mode() && nodes_empty(cs->mems_allowed)))
+		return -ENOSPC;
+	return 0;
+}
+
 /* Called by cgroups to determine if a cpuset is usable; cpuset_rwsem held */
 static int cpuset_can_attach(struct cgroup_taskset *tset)
 {
@@ -2459,16 +2481,9 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
 
 	percpu_down_write(&cpuset_rwsem);
 
-	/* allow moving tasks into an empty cpuset if on default hierarchy */
-	ret = -ENOSPC;
-	if (!is_in_v2_mode() &&
-	    (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
-		goto out_unlock;
-
-	/*
-	 * Task cannot be moved to a cpuset with empty effective cpus.
-	 */
-	if (cpumask_empty(cs->effective_cpus))
+	/* Check to see if task is allowed in the cpuset */
+	ret = cpuset_can_attach_check(cs);
+	if (ret)
 		goto out_unlock;
 
 	cgroup_taskset_for_each(task, css, tset) {
@@ -2485,7 +2500,6 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
 	 * changes which zero cpus/mems_allowed.
 	 */
 	cs->attach_in_progress++;
-	ret = 0;
 out_unlock:
 	percpu_up_write(&cpuset_rwsem);
 	return ret;
@@ -2494,25 +2508,47 @@ out_unlock:
 static void cpuset_cancel_attach(struct cgroup_taskset *tset)
 {
 	struct cgroup_subsys_state *css;
+	struct cpuset *cs;
 
 	cgroup_taskset_first(tset, &css);
+	cs = css_cs(css);
 
 	percpu_down_write(&cpuset_rwsem);
-	css_cs(css)->attach_in_progress--;
+	cs->attach_in_progress--;
+	if (!cs->attach_in_progress)
+		wake_up(&cpuset_attach_wq);
 	percpu_up_write(&cpuset_rwsem);
 }
 
 /*
- * Protected by cpuset_rwsem.  cpus_attach is used only by cpuset_attach()
+ * Protected by cpuset_rwsem. cpus_attach is used only by cpuset_attach_task()
  * but we can't allocate it dynamically there.  Define it global and
  * allocate from cpuset_init().
  */
 static cpumask_var_t cpus_attach;
+static nodemask_t cpuset_attach_nodemask_to;
+
+static void cpuset_attach_task(struct cpuset *cs, struct task_struct *task)
+{
+	percpu_rwsem_assert_held(&cpuset_rwsem);
+
+	if (cs != &top_cpuset)
+		guarantee_online_cpus(task, cpus_attach);
+	else
+		cpumask_andnot(cpus_attach, task_cpu_possible_mask(task),
+			       cs->subparts_cpus);
+	/*
+	 * can_attach beforehand should guarantee that this doesn't
+	 * fail.  TODO: have a better way to handle failure here
+	 */
+	WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach));
+
+	cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to);
+	cpuset_update_task_spread_flags(cs, task);
+}
 
 static void cpuset_attach(struct cgroup_taskset *tset)
 {
-	/* static buf protected by cpuset_rwsem */
-	static nodemask_t cpuset_attach_nodemask_to;
 	struct task_struct *task;
 	struct task_struct *leader;
 	struct cgroup_subsys_state *css;
@@ -2543,20 +2579,8 @@ static void cpuset_attach(struct cgroup_taskset *tset)
 
 	guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
 
-	cgroup_taskset_for_each(task, css, tset) {
-		if (cs != &top_cpuset)
-			guarantee_online_cpus(task, cpus_attach);
-		else
-			cpumask_copy(cpus_attach, task_cpu_possible_mask(task));
-		/*
-		 * can_attach beforehand should guarantee that this doesn't
-		 * fail.  TODO: have a better way to handle failure here
-		 */
-		WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach));
-
-		cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to);
-		cpuset_update_task_spread_flags(cs, task);
-	}
+	cgroup_taskset_for_each(task, css, tset)
+		cpuset_attach_task(cs, task);
 
 	/*
 	 * Change mm for all threadgroup leaders. This is expensive and may
@@ -3248,17 +3272,101 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css)
 }
 
 /*
+ * In case the child is cloned into a cpuset different from its parent,
+ * additional checks are done to see if the move is allowed.
+ */
+static int cpuset_can_fork(struct task_struct *task, struct css_set *cset)
+{
+	struct cpuset *cs = css_cs(cset->subsys[cpuset_cgrp_id]);
+	bool same_cs;
+	int ret;
+
+	rcu_read_lock();
+	same_cs = (cs == task_cs(current));
+	rcu_read_unlock();
+
+	if (same_cs)
+		return 0;
+
+	lockdep_assert_held(&cgroup_mutex);
+	percpu_down_write(&cpuset_rwsem);
+
+	/* Check to see if task is allowed in the cpuset */
+	ret = cpuset_can_attach_check(cs);
+	if (ret)
+		goto out_unlock;
+
+	ret = task_can_attach(task, cs->effective_cpus);
+	if (ret)
+		goto out_unlock;
+
+	ret = security_task_setscheduler(task);
+	if (ret)
+		goto out_unlock;
+
+	/*
+	 * Mark attach is in progress.  This makes validate_change() fail
+	 * changes which zero cpus/mems_allowed.
+	 */
+	cs->attach_in_progress++;
+out_unlock:
+	percpu_up_write(&cpuset_rwsem);
+	return ret;
+}
+
+static void cpuset_cancel_fork(struct task_struct *task, struct css_set *cset)
+{
+	struct cpuset *cs = css_cs(cset->subsys[cpuset_cgrp_id]);
+	bool same_cs;
+
+	rcu_read_lock();
+	same_cs = (cs == task_cs(current));
+	rcu_read_unlock();
+
+	if (same_cs)
+		return;
+
+	percpu_down_write(&cpuset_rwsem);
+	cs->attach_in_progress--;
+	if (!cs->attach_in_progress)
+		wake_up(&cpuset_attach_wq);
+	percpu_up_write(&cpuset_rwsem);
+}
+
+/*
  * Make sure the new task conform to the current state of its parent,
  * which could have been changed by cpuset just after it inherits the
  * state from the parent and before it sits on the cgroup's task list.
  */
 static void cpuset_fork(struct task_struct *task)
 {
-	if (task_css_is_root(task, cpuset_cgrp_id))
+	struct cpuset *cs;
+	bool same_cs;
+
+	rcu_read_lock();
+	cs = task_cs(task);
+	same_cs = (cs == task_cs(current));
+	rcu_read_unlock();
+
+	if (same_cs) {
+		if (cs == &top_cpuset)
+			return;
+
+		set_cpus_allowed_ptr(task, current->cpus_ptr);
+		task->mems_allowed = current->mems_allowed;
 		return;
+	}
+
+	/* CLONE_INTO_CGROUP */
+	percpu_down_write(&cpuset_rwsem);
+	guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
+	cpuset_attach_task(cs, task);
+
+	cs->attach_in_progress--;
+	if (!cs->attach_in_progress)
+		wake_up(&cpuset_attach_wq);
 
-	set_cpus_allowed_ptr(task, current->cpus_ptr);
-	task->mems_allowed = current->mems_allowed;
+	percpu_up_write(&cpuset_rwsem);
 }
 
 struct cgroup_subsys cpuset_cgrp_subsys = {
@@ -3271,6 +3379,8 @@ struct cgroup_subsys cpuset_cgrp_subsys = {
 	.attach		= cpuset_attach,
 	.post_attach	= cpuset_post_attach,
 	.bind		= cpuset_bind,
+	.can_fork	= cpuset_can_fork,
+	.cancel_fork	= cpuset_cancel_fork,
 	.fork		= cpuset_fork,
 	.legacy_cftypes	= legacy_files,
 	.dfl_cftypes	= dfl_files,
diff --git a/kernel/cgroup/legacy_freezer.c b/kernel/cgroup/legacy_freezer.c
index 1b6b21851e9d..936473203a6b 100644
--- a/kernel/cgroup/legacy_freezer.c
+++ b/kernel/cgroup/legacy_freezer.c
@@ -22,6 +22,7 @@
 #include <linux/freezer.h>
 #include <linux/seq_file.h>
 #include <linux/mutex.h>
+#include <linux/cpu.h>
 
 /*
  * A cgroup is freezing if any FREEZING flags are set.  FREEZING_SELF is
@@ -350,7 +351,7 @@ static void freezer_apply_state(struct freezer *freezer, bool freeze,
 
 	if (freeze) {
 		if (!(freezer->state & CGROUP_FREEZING))
-			static_branch_inc(&freezer_active);
+			static_branch_inc_cpuslocked(&freezer_active);
 		freezer->state |= state;
 		freeze_cgroup(freezer);
 	} else {
@@ -361,7 +362,7 @@ static void freezer_apply_state(struct freezer *freezer, bool freeze,
 		if (!(freezer->state & CGROUP_FREEZING)) {
 			freezer->state &= ~CGROUP_FROZEN;
 			if (was_freezing)
-				static_branch_dec(&freezer_active);
+				static_branch_dec_cpuslocked(&freezer_active);
 			unfreeze_cgroup(freezer);
 		}
 	}
@@ -379,6 +380,7 @@ static void freezer_change_state(struct freezer *freezer, bool freeze)
 {
 	struct cgroup_subsys_state *pos;
 
+	cpus_read_lock();
 	/*
 	 * Update all its descendants in pre-order traversal.  Each
 	 * descendant will try to inherit its parent's FREEZING state as
@@ -407,6 +409,7 @@ static void freezer_change_state(struct freezer *freezer, bool freeze)
 	}
 	rcu_read_unlock();
 	mutex_unlock(&freezer_mutex);
+	cpus_read_unlock();
 }
 
 static ssize_t freezer_write(struct kernfs_open_file *of,
diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c
index 831f1f472bb8..0a2b4967e333 100644
--- a/kernel/cgroup/rstat.c
+++ b/kernel/cgroup/rstat.c
@@ -457,9 +457,7 @@ static void root_cgroup_cputime(struct cgroup_base_stat *bstat)
 	struct task_cputime *cputime = &bstat->cputime;
 	int i;
 
-	cputime->stime = 0;
-	cputime->utime = 0;
-	cputime->sum_exec_runtime = 0;
+	memset(bstat, 0, sizeof(*bstat));
 	for_each_possible_cpu(i) {
 		struct kernel_cpustat kcpustat;
 		u64 *cpustat = kcpustat.cpustat;
diff --git a/kernel/fork.c b/kernel/fork.c
index 0c92f224c68c..ea332319dffe 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1174,6 +1174,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 fail_pcpu:
 	while (i > 0)
 		percpu_counter_destroy(&mm->rss_stat[--i]);
+	destroy_context(mm);
 fail_nocontext:
 	mm_free_pgd(mm);
 fail_nopgd:
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 6986ea31c984..5f6587d94c1d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10238,6 +10238,16 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
 
 		sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) /
 				sds->total_capacity;
+
+		/*
+		 * If the local group is more loaded than the average system
+		 * load, don't try to pull any tasks.
+		 */
+		if (local->avg_load >= sds->avg_load) {
+			env->imbalance = 0;
+			return;
+		}
+
 	}
 
 	/*
diff --git a/kernel/sys.c b/kernel/sys.c
index 495cd87d9bf4..351de7916302 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -664,6 +664,7 @@ long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
 	struct cred *new;
 	int retval;
 	kuid_t kruid, keuid, ksuid;
+	bool ruid_new, euid_new, suid_new;
 
 	kruid = make_kuid(ns, ruid);
 	keuid = make_kuid(ns, euid);
@@ -678,25 +679,29 @@ long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
 	if ((suid != (uid_t) -1) && !uid_valid(ksuid))
 		return -EINVAL;
 
+	old = current_cred();
+
+	/* check for no-op */
+	if ((ruid == (uid_t) -1 || uid_eq(kruid, old->uid)) &&
+	    (euid == (uid_t) -1 || (uid_eq(keuid, old->euid) &&
+				    uid_eq(keuid, old->fsuid))) &&
+	    (suid == (uid_t) -1 || uid_eq(ksuid, old->suid)))
+		return 0;
+
+	ruid_new = ruid != (uid_t) -1        && !uid_eq(kruid, old->uid) &&
+		   !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid);
+	euid_new = euid != (uid_t) -1        && !uid_eq(keuid, old->uid) &&
+		   !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid);
+	suid_new = suid != (uid_t) -1        && !uid_eq(ksuid, old->uid) &&
+		   !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid);
+	if ((ruid_new || euid_new || suid_new) &&
+	    !ns_capable_setid(old->user_ns, CAP_SETUID))
+		return -EPERM;
+
 	new = prepare_creds();
 	if (!new)
 		return -ENOMEM;
 
-	old = current_cred();
-
-	retval = -EPERM;
-	if (!ns_capable_setid(old->user_ns, CAP_SETUID)) {
-		if (ruid != (uid_t) -1        && !uid_eq(kruid, old->uid) &&
-		    !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid))
-			goto error;
-		if (euid != (uid_t) -1        && !uid_eq(keuid, old->uid) &&
-		    !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid))
-			goto error;
-		if (suid != (uid_t) -1        && !uid_eq(ksuid, old->uid) &&
-		    !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid))
-			goto error;
-	}
-
 	if (ruid != (uid_t) -1) {
 		new->uid = kruid;
 		if (!uid_eq(kruid, old->uid)) {
@@ -761,6 +766,7 @@ long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
 	struct cred *new;
 	int retval;
 	kgid_t krgid, kegid, ksgid;
+	bool rgid_new, egid_new, sgid_new;
 
 	krgid = make_kgid(ns, rgid);
 	kegid = make_kgid(ns, egid);
@@ -773,23 +779,28 @@ long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
 	if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
 		return -EINVAL;
 
+	old = current_cred();
+
+	/* check for no-op */
+	if ((rgid == (gid_t) -1 || gid_eq(krgid, old->gid)) &&
+	    (egid == (gid_t) -1 || (gid_eq(kegid, old->egid) &&
+				    gid_eq(kegid, old->fsgid))) &&
+	    (sgid == (gid_t) -1 || gid_eq(ksgid, old->sgid)))
+		return 0;
+
+	rgid_new = rgid != (gid_t) -1        && !gid_eq(krgid, old->gid) &&
+		   !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid);
+	egid_new = egid != (gid_t) -1        && !gid_eq(kegid, old->gid) &&
+		   !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid);
+	sgid_new = sgid != (gid_t) -1        && !gid_eq(ksgid, old->gid) &&
+		   !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid);
+	if ((rgid_new || egid_new || sgid_new) &&
+	    !ns_capable_setid(old->user_ns, CAP_SETGID))
+		return -EPERM;
+
 	new = prepare_creds();
 	if (!new)
 		return -ENOMEM;
-	old = current_cred();
-
-	retval = -EPERM;
-	if (!ns_capable_setid(old->user_ns, CAP_SETGID)) {
-		if (rgid != (gid_t) -1        && !gid_eq(krgid, old->gid) &&
-		    !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid))
-			goto error;
-		if (egid != (gid_t) -1        && !gid_eq(kegid, old->gid) &&
-		    !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid))
-			goto error;
-		if (sgid != (gid_t) -1        && !gid_eq(ksgid, old->gid) &&
-		    !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid))
-			goto error;
-	}
 
 	if (rgid != (gid_t) -1)
 		new->gid = krgid;