diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/proc/Makefile | 1 | ||||
| -rw-r--r-- | fs/proc/base.c | 15 | ||||
| -rw-r--r-- | fs/proc/inode.c | 7 | ||||
| -rw-r--r-- | fs/proc/internal.h | 6 | ||||
| -rw-r--r-- | fs/proc/root.c | 3 | ||||
| -rw-r--r-- | fs/proc/thread_self.c | 85 |
6 files changed, 111 insertions, 6 deletions
diff --git a/fs/proc/Makefile b/fs/proc/Makefile index 239493e..7151ea4 100644 --- a/fs/proc/Makefile +++ b/fs/proc/Makefile @@ -23,6 +23,7 @@ proc-y += version.o proc-y += softirqs.o proc-y += namespaces.o proc-y += self.o +proc-y += thread_self.o proc-$(CONFIG_PROC_SYSCTL) += proc_sysctl.o proc-$(CONFIG_NET) += proc_net.o proc-$(CONFIG_PROC_KCORE) += kcore.o diff --git a/fs/proc/base.c b/fs/proc/base.c index ed34e40..0131156 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2847,7 +2847,7 @@ retry: return iter; } -#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 1) +#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) /* for the /proc/ directory itself, after non-process stuff has been done */ int proc_pid_readdir(struct file *file, struct dir_context *ctx) @@ -2859,14 +2859,19 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx) if (pos >= PID_MAX_LIMIT + TGID_OFFSET) return 0; - if (pos == TGID_OFFSET - 1) { + if (pos == TGID_OFFSET - 2) { struct inode *inode = ns->proc_self->d_inode; if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) return 0; - iter.tgid = 0; - } else { - iter.tgid = pos - TGID_OFFSET; + ctx->pos = pos = pos + 1; + } + if (pos == TGID_OFFSET - 1) { + struct inode *inode = ns->proc_thread_self->d_inode; + if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) + return 0; + ctx->pos = pos = pos + 1; } + iter.tgid = pos - TGID_OFFSET; iter.task = NULL; for (iter = next_tgid(ns, iter); iter.task; diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 0adbc02..333080d 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -442,6 +442,7 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de) int proc_fill_super(struct super_block *s) { struct inode *root_inode; + int ret; s->s_flags |= MS_NODIRATIME | MS_NOSUID | MS_NOEXEC; s->s_blocksize = 1024; @@ -463,5 +464,9 @@ int proc_fill_super(struct super_block *s) return -ENOMEM; } - return proc_setup_self(s); + ret = proc_setup_self(s); + if (ret) { + return ret; + } + return proc_setup_thread_self(s); } diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 3ab6d14..ee04619 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -234,6 +234,12 @@ static inline int proc_net_init(void) { return 0; } extern int proc_setup_self(struct super_block *); /* + * proc_thread_self.c + */ +extern int proc_setup_thread_self(struct super_block *); +extern void proc_thread_self_init(void); + +/* * proc_sysctl.c */ #ifdef CONFIG_PROC_SYSCTL diff --git a/fs/proc/root.c b/fs/proc/root.c index 5dbadec..48f1c03 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -149,6 +149,8 @@ static void proc_kill_sb(struct super_block *sb) ns = (struct pid_namespace *)sb->s_fs_info; if (ns->proc_self) dput(ns->proc_self); + if (ns->proc_thread_self) + dput(ns->proc_thread_self); kill_anon_super(sb); put_pid_ns(ns); } @@ -170,6 +172,7 @@ void __init proc_root_init(void) return; proc_self_init(); + proc_thread_self_init(); proc_symlink("mounts", NULL, "self/mounts"); proc_net_init(); diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c new file mode 100644 index 0000000..59075b5 --- /dev/null +++ b/fs/proc/thread_self.c @@ -0,0 +1,85 @@ +#include <linux/sched.h> +#include <linux/namei.h> +#include <linux/slab.h> +#include <linux/pid_namespace.h> +#include "internal.h" + +/* + * /proc/thread_self: + */ +static int proc_thread_self_readlink(struct dentry *dentry, char __user *buffer, + int buflen) +{ + struct pid_namespace *ns = dentry->d_sb->s_fs_info; + pid_t tgid = task_tgid_nr_ns(current, ns); + pid_t pid = task_pid_nr_ns(current, ns); + char tmp[PROC_NUMBUF + 6 + PROC_NUMBUF]; + if (!pid) + return -ENOENT; + sprintf(tmp, "%d/task/%d", tgid, pid); + return readlink_copy(buffer, buflen, tmp); +} + +static void *proc_thread_self_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + struct pid_namespace *ns = dentry->d_sb->s_fs_info; + pid_t tgid = task_tgid_nr_ns(current, ns); + pid_t pid = task_pid_nr_ns(current, ns); + char *name = ERR_PTR(-ENOENT); + if (pid) { + name = kmalloc(PROC_NUMBUF + 6 + PROC_NUMBUF, GFP_KERNEL); + if (!name) + name = ERR_PTR(-ENOMEM); + else + sprintf(name, "%d/task/%d", tgid, pid); + } + nd_set_link(nd, name); + return NULL; +} + +static const struct inode_operations proc_thread_self_inode_operations = { + .readlink = proc_thread_self_readlink, + .follow_link = proc_thread_self_follow_link, + .put_link = kfree_put_link, +}; + +static unsigned thread_self_inum; + +int proc_setup_thread_self(struct super_block *s) +{ + struct inode *root_inode = s->s_root->d_inode; + struct pid_namespace *ns = s->s_fs_info; + struct dentry *thread_self; + + mutex_lock(&root_inode->i_mutex); + thread_self = d_alloc_name(s->s_root, "thread-self"); + if (thread_self) { + struct inode *inode = new_inode_pseudo(s); + if (inode) { + inode->i_ino = thread_self_inum; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + inode->i_mode = S_IFLNK | S_IRWXUGO; + inode->i_uid = GLOBAL_ROOT_UID; + inode->i_gid = GLOBAL_ROOT_GID; + inode->i_op = &proc_thread_self_inode_operations; + d_add(thread_self, inode); + } else { + dput(thread_self); + thread_self = ERR_PTR(-ENOMEM); + } + } else { + thread_self = ERR_PTR(-ENOMEM); + } + mutex_unlock(&root_inode->i_mutex); + if (IS_ERR(thread_self)) { + pr_err("proc_fill_super: can't allocate /proc/thread_self\n"); + return PTR_ERR(thread_self); + } + ns->proc_thread_self = thread_self; + return 0; +} + +void __init proc_thread_self_init(void) +{ + proc_alloc_inum(&thread_self_inum); +} |
