autofs-5.0.4-expire-specific-submount-only.patch

   1 autofs-5.0.4 - expire specific submount only
   2
   3 From: Ian Kent <raven@themaw.net>
   4
   5 The submount shutdown at expire assumes that certain locks are not
   6 held but when notifying submounts containing nested submounts not
   7 all locks were being released. This leads to occassional deadlock
   8 when child submounts attempt to shutdown.
   9 ---
  10
  11  CHANGELOG    |    1 +
  12  lib/master.c |   33 ++++++++-------------------------
  13  2 files changed, 9 insertions(+), 25 deletions(-)
  14
  15
  16 diff --git a/CHANGELOG b/CHANGELOG
  17 index 4e8209e..88ca579 100644
  18 --- a/CHANGELOG
  19 +++ b/CHANGELOG
  20 @@ -1,6 +1,7 @@
  21  ??/??/2009 autofs-5.0.5
  22  -----------------------
  23  - fix dumb libxml2 check
  24 +- fix nested submount expire deadlock.
  25
  26  4/11/2008 autofs-5.0.4
  27  -----------------------
  28 diff --git a/lib/master.c b/lib/master.c
  29 index a243e6a..e1cc062 100644
  30 --- a/lib/master.c
  31 +++ b/lib/master.c
  32 @@ -834,7 +834,6 @@ int master_notify_submount(struct autofs_point *ap, const char *path, enum state
  33  {
  34         struct list_head *head, *p;
  35         struct autofs_point *this = NULL;
  36 -       size_t plen = strlen(path);
  37         int ret = 1;
  38
  39         mounts_mutex_lock(ap);
  40 @@ -842,37 +841,19 @@ int master_notify_submount(struct autofs_point *ap, const char *path, enum state
  41         head = &ap->submounts;
  42         p = head->prev;
  43         while (p != head) {
  44 -               size_t len;
  45 -
  46                 this = list_entry(p, struct autofs_point, mounts);
  47                 p = p->prev;
  48
  49                 if (!master_submount_list_empty(this)) {
  50 -                       if (!master_notify_submount(this, path, state)) {
  51 -                               ret = 0;
  52 -                               break;
  53 -                       }
  54 +                       mounts_mutex_unlock(ap);
  55 +                       return master_notify_submount(this, path, state);
  56                 }
  57
  58 -               len = strlen(this->path);
  59 -
  60 -               /* Initial path not the same */
  61 -               if (strncmp(this->path, path, len))
  62 +               /* path not the same */
  63 +               if (strcmp(this->path, path))
  64                         continue;
  65
  66 -               /*
  67 -                * Part of submount tree?
  68 -                * We must wait till we get to submount itself.
  69 -                * If it is tell caller by returning true.
  70 -                */
  71 -               if (plen > len) {
  72 -                       /* Not part of this directory tree */
  73 -                       if (path[len] != '/')
  74 -                               continue;
  75 -                       break;
  76 -               }
  77 -
  78 -               /* Now we have a submount to expire */
  79 +               /* Now we have found the submount we want to expire */
  80
  81                 st_mutex_lock();
  82
  83 @@ -901,8 +882,10 @@ int master_notify_submount(struct autofs_point *ap, const char *path, enum state
  84                         struct timespec t = { 0, 300000000 };
  85                         struct timespec r;
  86
  87 -                       if (this->state != ST_SHUTDOWN)
  88 +                       if (this->state != ST_SHUTDOWN) {
  89 +                               ret = 0;
  90                                 break;
  91 +                       }
  92
  93                         st_mutex_unlock();
  94                         mounts_mutex_unlock(ap);