diff options
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 8ac38beae360..ba6b03d4a85c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -23,6 +23,7 @@ #include <linux/sched/task_stack.h> #include <linux/sched/cputime.h> #include <linux/sched/ext.h> +#include <linux/sched/exec_state.h> #include <linux/seq_file.h> #include <linux/rtmutex.h> #include <linux/init.h> @@ -555,6 +556,7 @@ void free_task(struct task_struct *tsk) if (tsk->flags & PF_KTHREAD) free_kthread_struct(tsk); bpf_task_storage_free(tsk); + put_task_exec_state(rcu_access_pointer(tsk->exec_state)); free_task_struct(tsk); } EXPORT_SYMBOL(free_task); @@ -731,7 +733,6 @@ void __mmdrop(struct mm_struct *mm) destroy_context(mm); mmu_notifier_subscriptions_destroy(mm); check_mm(mm); - put_user_ns(mm->user_ns); mm_pasid_drop(mm); mm_destroy_cid(mm); percpu_counter_destroy_many(mm->rss_stat, NR_MM_COUNTERS); @@ -946,6 +947,8 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) tsk->seccomp.filter = NULL; #endif + RCU_INIT_POINTER(tsk->exec_state, NULL); + setup_thread_stack(tsk, orig); clear_user_return_notifier(tsk); clear_tsk_need_resched(tsk); @@ -1072,8 +1075,7 @@ static void mmap_init_lock(struct mm_struct *mm) #endif } -static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, - struct user_namespace *user_ns) +static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p) { mt_init_flags(&mm->mm_mt, MM_MT_FLAGS); mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock); @@ -1132,7 +1134,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, NR_MM_COUNTERS)) goto fail_pcpu; - mm->user_ns = get_user_ns(user_ns); lru_gen_init_mm(mm); return mm; @@ -1163,7 +1164,7 @@ struct mm_struct *mm_alloc(void) return NULL; memset(mm, 0, sizeof(*mm)); - return mm_init(mm, current, current_user_ns()); + return mm_init(mm, current); } EXPORT_SYMBOL_IF_KUNIT(mm_alloc); @@ -1527,7 +1528,7 @@ static struct mm_struct *dup_mm(struct task_struct *tsk, memcpy(mm, oldmm, sizeof(*mm)); - if (!mm_init(mm, tsk, mm->user_ns)) + if (!mm_init(mm, tsk)) goto fail_nomem; uprobe_start_dup_mmap(); @@ -1593,6 +1594,22 @@ static int copy_mm(u64 clone_flags, struct task_struct *tsk) return 0; } +static int copy_exec_state(u64 clone_flags, struct task_struct *tsk) +{ + struct task_exec_state *exec_state; + + /* CLONE_VM siblings refcount-share the parent's exec_state. */ + if (clone_flags & CLONE_VM) { + exec_state = rcu_dereference_protected(current->exec_state, true); + refcount_inc(&exec_state->count); + rcu_assign_pointer(tsk->exec_state, exec_state); + return 0; + } + + /* Everyone else inherits a fresh copy. */ + return task_exec_state_copy(tsk); +} + static int copy_fs(u64 clone_flags, struct task_struct *tsk) { struct fs_struct *fs = current->fs; @@ -2090,6 +2107,9 @@ __latent_entropy struct task_struct *copy_process( p = dup_task_struct(current, node); if (!p) goto fork_out; + retval = copy_exec_state(clone_flags, p); + if (retval) + goto bad_fork_free; p->flags &= ~PF_KTHREAD; if (args->kthread) p->flags |= PF_KTHREAD; @@ -3097,6 +3117,7 @@ void __init proc_caches_init(void) sizeof(struct signal_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL); + exec_state_init(); files_cachep = kmem_cache_create("files_cache", sizeof(struct files_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, |