autofs-5.0.4-uris-list-locking-fix.patch

   1 autofs-5.0.4 - uris list locking fix
   2
   3 From: Ian Kent <raven@themaw.net>
   4
   5 The ldap uris list doesn't need to change we just need to keep
   6 track of current server uri in the list and try to connect in
   7 a round robin order. Also it's possible multiple concurrent
   8 connection attempts may not be able to use the full list of
   9 servers (if one is present).
  10 ---
  11
  12  CHANGELOG             |    1 +
  13  include/lookup_ldap.h |    3 +-
  14  modules/lookup_ldap.c |   68 ++++++++++++++++++++++---------------------------
  15  3 files changed, 33 insertions(+), 39 deletions(-)
  16
  17
  18 diff --git a/CHANGELOG b/CHANGELOG
  19 index 3199e4d..b093451 100644
  20 --- a/CHANGELOG
  21 +++ b/CHANGELOG
  22 @@ -10,6 +10,7 @@
  23  - clear the quoted flag after each character from program map input.
  24  - use CLOEXEC flag for setmntent also.
  25  - fix hosts map use after free.
  26 +- fix uri list locking (again).
  27
  28  4/11/2008 autofs-5.0.4
  29  -----------------------
  30 diff --git a/include/lookup_ldap.h b/include/lookup_ldap.h
  31 index f9ed778..b47bf5d 100644
  32 --- a/include/lookup_ldap.h
  33 +++ b/include/lookup_ldap.h
  34 @@ -55,7 +55,8 @@ struct lookup_context {
  35          * given in configuration.
  36          */
  37         pthread_mutex_t uris_mutex;
  38 -       struct list_head *uri;
  39 +       struct list_head *uris;
  40 +       struct ldap_uri *uri;
  41         char *cur_host;
  42         struct ldap_searchdn *sdns;
  43
  44 diff --git a/modules/lookup_ldap.c b/modules/lookup_ldap.c
  45 index 6ba80eb..b6784e1 100644
  46 --- a/modules/lookup_ldap.c
  47 +++ b/modules/lookup_ldap.c
  48 @@ -137,7 +137,7 @@ static void uris_mutex_unlock(struct lookup_context *ctxt)
  49         return;
  50  }
  51
  52 -int bind_ldap_anonymous(unsigned logopt, LDAP *ldap, struct lookup_context *ctxt)
  53 +int bind_ldap_anonymous(unsigned logopt, LDAP *ldap, const char *uri, struct lookup_context *ctxt)
  54  {
  55         int rv;
  56
  57 @@ -147,16 +147,14 @@ int bind_ldap_anonymous(unsigned logopt, LDAP *ldap, struct lookup_context *ctxt
  58                 rv = ldap_simple_bind_s(ldap, NULL, NULL);
  59
  60         if (rv != LDAP_SUCCESS) {
  61 -               if (!ctxt->uri) {
  62 +               if (!ctxt->uris) {
  63                         crit(logopt, MODPREFIX
  64                              "Unable to bind to the LDAP server: "
  65                              "%s, error %s", ctxt->server ? "" : "(default)",
  66                              ldap_err2string(rv));
  67                 } else {
  68 -                       struct ldap_uri *uri;
  69 -                       uri = list_entry(ctxt->uri->next, struct ldap_uri, list);
  70                         info(logopt, MODPREFIX "Unable to bind to the LDAP server: "
  71 -                            "%s, error %s", uri->uri, ldap_err2string(rv));
  72 +                            "%s, error %s", uri, ldap_err2string(rv));
  73                 }
  74                 return -1;
  75         }
  76 @@ -498,7 +496,7 @@ static int find_query_dn(unsigned logopt, LDAP *ldap, struct lookup_context *ctx
  77         return 0;
  78  }
  79
  80 -static int do_bind(unsigned logopt, LDAP *ldap, struct lookup_context *ctxt)
  81 +static int do_bind(unsigned logopt, LDAP *ldap, const char *uri, struct lookup_context *ctxt)
  82  {
  83         char *host = NULL, *nhost;
  84         int rv, need_base = 1;
  85 @@ -511,11 +509,11 @@ static int do_bind(unsigned logopt, LDAP *ldap, struct lookup_context *ctxt)
  86                 rv = autofs_sasl_bind(logopt, ldap, ctxt);
  87                 debug(logopt, MODPREFIX "autofs_sasl_bind returned %d", rv);
  88         } else {
  89 -               rv = bind_ldap_anonymous(logopt, ldap, ctxt);
  90 +               rv = bind_ldap_anonymous(logopt, ldap, uri, ctxt);
  91                 debug(logopt, MODPREFIX "ldap anonymous bind returned %d", rv);
  92         }
  93  #else
  94 -       rv = bind_ldap_anonymous(logopt, ldap, ctxt);
  95 +       rv = bind_ldap_anonymous(logopt, ldap, uri, ctxt);
  96         debug(logopt, MODPREFIX "ldap anonymous bind returned %d", rv);
  97  #endif
  98
  99 @@ -584,7 +582,7 @@ static LDAP *do_connect(unsigned logopt, const char *uri, struct lookup_context
 100         if (!ldap)
 101                 return NULL;
 102
 103 -       if (!do_bind(logopt, ldap, ctxt)) {
 104 +       if (!do_bind(logopt, ldap, uri, ctxt)) {
 105                 unbind_ldap_connection(logopt, ldap, ctxt);
 106                 return NULL;
 107         }
 108 @@ -612,7 +610,7 @@ static LDAP *connect_to_server(unsigned logopt, const char *uri, struct lookup_c
 109                         return NULL;
 110                 }
 111
 112 -               if (!do_bind(logopt, ldap, ctxt)) {
 113 +               if (!do_bind(logopt, ldap, uri, ctxt)) {
 114                         unbind_ldap_connection(logopt, ldap, ctxt);
 115                         autofs_sasl_dispose(ctxt);
 116                         error(logopt, MODPREFIX "cannot bind to server");
 117 @@ -638,36 +636,34 @@ static LDAP *find_server(unsigned logopt, struct lookup_context *ctxt)
 118  {
 119         LDAP *ldap = NULL;
 120         struct ldap_uri *this;
 121 -       struct list_head *p;
 122 -       LIST_HEAD(tmp);
 123 +       struct list_head *p, *first;
 124
 125         /* Try each uri in list, add connect fails to tmp list */
 126         uris_mutex_lock(ctxt);
 127 -       p = ctxt->uri->next;
 128 -       while(p != ctxt->uri) {
 129 +       if (!ctxt->uri)
 130 +               first = ctxt->uris;
 131 +       else
 132 +               first = &ctxt->uri->list;
 133 +       uris_mutex_unlock(ctxt);
 134 +       p = first->next;
 135 +       while(p != first) {
 136 +               /* Skip list head */
 137 +               if (p == ctxt->uris) {
 138 +                       p = p->next;
 139 +                       continue;
 140 +               }
 141                 this = list_entry(p, struct ldap_uri, list);
 142 -               uris_mutex_unlock(ctxt);
 143                 debug(logopt, "trying server %s", this->uri);
 144                 ldap = connect_to_server(logopt, this->uri, ctxt);
 145                 if (ldap) {
 146                         info(logopt, "connected to uri %s", this->uri);
 147                         uris_mutex_lock(ctxt);
 148 +                       ctxt->uri = this;
 149 +                       uris_mutex_unlock(ctxt);
 150                         break;
 151                 }
 152 -               uris_mutex_lock(ctxt);
 153                 p = p->next;
 154 -               list_del_init(&this->list);
 155 -               list_add_tail(&this->list, &tmp);
 156         }
 157 -       /*
 158 -        * Successfuly connected uri (head of list) and untried uris are
 159 -        * in ctxt->uri list. Make list of remainder and failed uris with
 160 -        * failed uris at end and assign back to ctxt-uri.
 161 -        */
 162 -       list_splice(ctxt->uri, &tmp);
 163 -       INIT_LIST_HEAD(ctxt->uri);
 164 -       list_splice(&tmp, ctxt->uri);
 165 -       uris_mutex_unlock(ctxt);
 166
 167         return ldap;
 168  }
 169 @@ -677,23 +673,19 @@ static LDAP *do_reconnect(unsigned logopt, struct lookup_context *ctxt)
 170         struct ldap_uri *this;
 171         LDAP *ldap;
 172
 173 -       if (ctxt->server || !ctxt->uri) {
 174 +       if (ctxt->server || !ctxt->uris) {
 175                 ldap = do_connect(logopt, ctxt->server, ctxt);
 176                 return ldap;
 177         }
 178
 179         uris_mutex_lock(ctxt);
 180 -       this = list_entry(ctxt->uri->next, struct ldap_uri, list);
 181 +       this = ctxt->uri;
 182         uris_mutex_unlock(ctxt);
 183         ldap = do_connect(logopt, this->uri, ctxt);
 184         if (ldap)
 185                 return ldap;
 186
 187 -       /* Failed to connect, put at end of list */
 188 -       uris_mutex_lock(ctxt);
 189 -       list_del_init(&this->list);
 190 -       list_add_tail(&this->list, ctxt->uri);
 191 -       uris_mutex_unlock(ctxt);
 192 +       /* Failed to connect, try to find a new server */
 193
 194  #ifdef WITH_SASL
 195         autofs_sasl_dispose(ctxt);
 196 @@ -1259,8 +1251,8 @@ static void free_context(struct lookup_context *ctxt)
 197                 free(ctxt->cur_host);
 198         if (ctxt->base)
 199                 free(ctxt->base);
 200 -       if (ctxt->uri)
 201 -               defaults_free_uris(ctxt->uri);
 202 +       if (ctxt->uris)
 203 +               defaults_free_uris(ctxt->uris);
 204         ret = pthread_mutex_destroy(&ctxt->uris_mutex);
 205         if (ret)
 206                 fatal(ret);
 207 @@ -1344,7 +1336,7 @@ int lookup_init(const char *mapfmt, int argc, const char *const *argv, void **co
 208                 if (uris) {
 209                         validate_uris(uris);
 210                         if (!list_empty(uris))
 211 -                               ctxt->uri = uris;
 212 +                               ctxt->uris = uris;
 213                         else {
 214                                 error(LOGOPT_ANY,
 215                                       "no valid uris found in config list"
 216 @@ -1375,7 +1367,7 @@ int lookup_init(const char *mapfmt, int argc, const char *const *argv, void **co
 217         }
 218  #endif
 219
 220 -       if (ctxt->server || !ctxt->uri) {
 221 +       if (ctxt->server || !ctxt->uris) {
 222                 ldap = connect_to_server(LOGOPT_NONE, ctxt->server, ctxt);
 223                 if (!ldap) {
 224                         free_context(ctxt);