[src/trunk]: src/sys/miscfs/procfs provide a root entry if one was not found.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/50c7650b3182
branches:  trunk
changeset: 772071:50c7650b3182
user:      christos <christos%NetBSD.org@localhost>
date:      Fri Dec 16 20:45:07 2011 +0000

description:
provide a root entry if one was not found.

diffstat:

 sys/miscfs/procfs/procfs_linux.c |  82 ++++++++++++++++++++++++---------------
 1 files changed, 50 insertions(+), 32 deletions(-)

diffs (130 lines):

diff -r 3b49d112a246 -r 50c7650b3182 sys/miscfs/procfs/procfs_linux.c
--- a/sys/miscfs/procfs/procfs_linux.c  Fri Dec 16 17:37:14 2011 +0000
+++ b/sys/miscfs/procfs/procfs_linux.c  Fri Dec 16 20:45:07 2011 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: procfs_linux.c,v 1.62 2011/12/15 20:55:02 christos Exp $      */
+/*      $NetBSD: procfs_linux.c,v 1.63 2011/12/16 20:45:07 christos Exp $      */
 
 /*
  * Copyright (c) 2001 Wasabi Systems, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: procfs_linux.c,v 1.62 2011/12/15 20:55:02 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: procfs_linux.c,v 1.63 2011/12/16 20:45:07 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -55,6 +55,7 @@
 #include <sys/conf.h>
 #include <sys/sysctl.h>
 #include <sys/kauth.h>
+#include <sys/filedesc.h>
 
 #include <miscfs/procfs/procfs.h>
 
@@ -557,56 +558,73 @@
        return error;
 }
 
+static int
+procfs_format_sfs(char **mtab, size_t *mlen, char *buf, size_t blen,
+    const struct statvfs *sfs, struct lwp *curl, int suser)
+{
+       const char *fsname;
+
+       /* Linux uses different names for some filesystems */
+       fsname = sfs->f_fstypename;
+       if (strcmp(fsname, "procfs") == 0)
+               fsname = "proc";
+       else if (strcmp(fsname, "ext2fs") == 0)
+               fsname = "ext2";
+
+       blen = snprintf(buf, blen, "%s %s %s %s%s%s%s%s%s 0 0\n",
+           sfs->f_mntfromname, sfs->f_mntonname, fsname,
+           (sfs->f_flag & ST_RDONLY) ? "ro" : "rw",
+           (sfs->f_flag & ST_NOSUID) ? ",nosuid" : "",
+           (sfs->f_flag & ST_NOEXEC) ? ",noexec" : "",
+           (sfs->f_flag & ST_NODEV) ? ",nodev" : "",
+           (sfs->f_flag & ST_SYNCHRONOUS) ? ",sync" : "",
+           (sfs->f_flag & ST_NOATIME) ? ",noatime" : "");
+
+       *mtab = realloc(*mtab, *mlen + blen, M_TEMP, M_WAITOK);
+       memcpy(*mtab + *mlen, buf, blen);
+       *mlen += blen;
+       return sfs->f_mntonname[0] == '/' && sfs->f_mntonname[1] == '\0';
+}
+
 int
 procfs_domounts(struct lwp *curl, struct proc *p,
     struct pfsnode *pfs, struct uio *uio)
 {
        char *bf, *mtab = NULL;
-       const char *fsname;
-       size_t len, mtabsz = 0;
+       size_t mtabsz = 0;
        struct mount *mp, *nmp;
-       struct statvfs sfs;
-       int error = 0, suser;
+       int error = 0, suser, root = 0;
+       struct cwdinfo *cwdi = curl->l_proc->p_cwdi;
 
        suser = kauth_authorize_generic(curl->l_cred,
            KAUTH_GENERIC_ISSUSER, NULL) == 0;
 
        bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
+
        mutex_enter(&mountlist_lock);
        for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
-            mp = nmp) {
+           mp = nmp) {
+               struct statvfs sfs;
+
                if (vfs_busy(mp, &nmp))
                        continue;
 
-               if (dostatvfs(mp, &sfs, curl, MNT_WAIT, suser) != 0)
-                       continue;
-
-               /* Linux uses different names for some filesystems */
-               fsname = sfs.f_fstypename;
-               if (strcmp(fsname, "procfs") == 0)
-                       fsname = "proc";
-               else if (strcmp(fsname, "ext2fs") == 0)
-                       fsname = "ext2";
-
-               len = snprintf(bf, LBFSZ, "%s %s %s %s%s%s%s%s%s 0 0\n",
-                       sfs.f_mntfromname,
-                       sfs.f_mntonname,
-                       fsname,
-                       (sfs.f_flag & ST_RDONLY) ? "ro" : "rw",
-                       (sfs.f_flag & ST_NOSUID) ? ",nosuid" : "",
-                       (sfs.f_flag & ST_NOEXEC) ? ",noexec" : "",
-                       (sfs.f_flag & ST_NODEV) ? ",nodev" : "",
-                       (sfs.f_flag & ST_SYNCHRONOUS) ? ",sync" : "",
-                       (sfs.f_flag & ST_NOATIME) ? ",noatime" : ""
-                       );
-
-               mtab = realloc(mtab, mtabsz + len, M_TEMP, M_WAITOK);
-               memcpy(mtab + mtabsz, bf, len);
-               mtabsz += len;
+               if ((error = dostatvfs(mp, &sfs, curl, MNT_WAIT, suser)) == 0)
+                       root |= procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
+                           &sfs, curl, suser);
 
                vfs_unbusy(mp, false, &nmp);
        }
        mutex_exit(&mountlist_lock);
+
+       /*
+        * If we are inside a chroot that is not itself a mount point,
+        * fake a root entry.
+        */
+       if (!root && cwdi->cwdi_rdir)
+               (void)procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
+                   &cwdi->cwdi_rdir->v_mount->mnt_stat, curl, 1);
+
        free(bf, M_TEMP);
 
        if (mtabsz > 0) {