From 4eeac1c26065d78a0c52c9764777094f3d8ab30d Mon Sep 17 00:00:00 2001
From: CyberLeo <cyberleo@cyberleo.net>
Date: Mon, 20 Dec 2010 11:24:34 -0600
Subject: [PATCH] [CDN-Patch] sys/fs/procfs: extend procfs to support
 proc/self, proc/pid/cwd, proc/pid/exe

---
 sys/fs/procfs/procfs.c | 47 ++++++++++++++++++++++++++++++++++++++++++
 sys/fs/procfs/procfs.h |  2 ++
 2 files changed, 49 insertions(+)

diff --git a/sys/fs/procfs/procfs.c b/sys/fs/procfs/procfs.c
index 8b69eb1a..a0bf3567 100644
--- a/sys/fs/procfs/procfs.c
+++ b/sys/fs/procfs/procfs.c
@@ -60,6 +60,44 @@
 
 #include <fs/pseudofs/pseudofs.h>
 #include <fs/procfs/procfs.h>
+#include <sys/filedesc.h>
+#include <sys/jail.h>
+
+/*
+ * Filler function for proc/pid/cwd
+ * Copied verbatim from src/sys/compat/linprocfs/linprocfs.c,v 1.119
+ */
+int
+procfs_doproccwd(PFS_FILL_ARGS)
+{
+	char *fullpath = "unknown";
+	char *freepath = NULL;
+
+	vn_fullpath(td, p->p_fd->fd_cdir, &fullpath, &freepath);
+	sbuf_printf(sb, "%s", fullpath);
+	if (freepath)
+		free(freepath, M_TEMP);
+	return (0);
+}
+
+/*
+ * Filler function for proc/pid/root
+ * Copied verbatim from src/sys/compat/linprocfs/linprocfs.c,v 1.119
+ */
+int
+procfs_doprocroot(PFS_FILL_ARGS)
+{
+	struct vnode *rvp;
+	char *fullpath = "unknown";
+	char *freepath = NULL;
+
+	rvp = jailed(p->p_ucred) ? p->p_fd->fd_jdir : p->p_fd->fd_rdir;
+	vn_fullpath(td, rvp, &fullpath, &freepath);
+	sbuf_printf(sb, "%s", fullpath);
+	if (freepath)
+		free(freepath, M_TEMP);
+	return (0);
+}
 
 /*
  * Filler function for proc/pid/self
@@ -158,6 +196,8 @@ procfs_init(PFS_INIT_ARGS)
 
 	pfs_create_link(root, "curproc", procfs_docurproc,
 	    NULL, NULL, NULL, 0);
+	pfs_create_link(root, "self", procfs_docurproc,
+	    NULL, NULL, NULL, 0);
 
 	dir = pfs_create_dir(root, "pid",
 	    procfs_attr, NULL, NULL, PFS_PROCDEP);
@@ -192,6 +232,13 @@ procfs_init(PFS_INIT_ARGS)
 
 	pfs_create_link(dir, "file", procfs_doprocfile,
 	    NULL, procfs_notsystem, NULL, 0);
+	pfs_create_link(dir, "exe", procfs_doprocfile,
+	    NULL, procfs_notsystem, NULL, 0);
+
+	pfs_create_link(dir, "cwd", &procfs_doproccwd,
+	    NULL, NULL, NULL, 0);
+	pfs_create_link(dir, "root", &procfs_doprocroot,
+	    NULL, NULL, NULL, 0);
 
 	return (0);
 }
diff --git a/sys/fs/procfs/procfs.h b/sys/fs/procfs/procfs.h
index 25982245..b90e4152 100644
--- a/sys/fs/procfs/procfs.h
+++ b/sys/fs/procfs/procfs.h
@@ -38,6 +38,8 @@
 
 #ifdef _KERNEL
 
+int	 procfs_doproccwd(PFS_FILL_ARGS);
+int	 procfs_doprocroot(PFS_FILL_ARGS);
 int	 procfs_docurproc(PFS_FILL_ARGS);
 int	 procfs_doosrel(PFS_FILL_ARGS);
 int	 procfs_doproccmdline(PFS_FILL_ARGS);
-- 
2.45.0