diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index cf637bc4ab453..6e36e854b5124 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -68,6 +68,8 @@ static inline struct cgroup_fs_context *cgroup_fc2context(struct fs_context *fc) struct cgroup_pidlist; struct cgroup_file_ctx { + struct cgroup_namespace *ns; + struct { void *trigger; } psi; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index abb70c55201ca..bb1a78ff14374 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -3822,14 +3822,19 @@ static int cgroup_file_open(struct kernfs_open_file *of) 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) + if (ret) { + put_cgroup_ns(ctx->ns); kfree(ctx); + } return ret; } @@ -3840,13 +3845,14 @@ static void cgroup_file_release(struct kernfs_open_file *of) 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; @@ -3863,7 +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) @@ -4853,9 +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; @@ -4884,11 +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; @@ -4905,6 +4912,7 @@ 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; @@ -4932,7 +4940,8 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf, */ 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; @@ -6149,7 +6158,8 @@ 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;