[NETFILTER]: Remove tasklist_lock abuse in ipt{,6}owner
Christoph Hellwig [Mon, 15 Aug 2005 00:33:59 +0000 (17:33 -0700)]
Rip out cmd/sid/pid matching since its unfixable broken and stands in the
way of locking changes to tasklist_lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ipt_owner.c
net/ipv6/netfilter/ip6t_owner.c

index 3b9065e..c1889f8 100644 (file)
@@ -21,106 +21,6 @@ MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
 MODULE_DESCRIPTION("iptables owner match");
 
 static int
-match_comm(const struct sk_buff *skb, const char *comm)
-{
-       struct task_struct *g, *p;
-       struct files_struct *files;
-       int i;
-
-       read_lock(&tasklist_lock);
-       do_each_thread(g, p) {
-               if(strncmp(p->comm, comm, sizeof(p->comm)))
-                       continue;
-
-               task_lock(p);
-               files = p->files;
-               if(files) {
-                       spin_lock(&files->file_lock);
-                       for (i=0; i < files->max_fds; i++) {
-                               if (fcheck_files(files, i) ==
-                                   skb->sk->sk_socket->file) {
-                                       spin_unlock(&files->file_lock);
-                                       task_unlock(p);
-                                       read_unlock(&tasklist_lock);
-                                       return 1;
-                               }
-                       }
-                       spin_unlock(&files->file_lock);
-               }
-               task_unlock(p);
-       } while_each_thread(g, p);
-       read_unlock(&tasklist_lock);
-       return 0;
-}
-
-static int
-match_pid(const struct sk_buff *skb, pid_t pid)
-{
-       struct task_struct *p;
-       struct files_struct *files;
-       int i;
-
-       read_lock(&tasklist_lock);
-       p = find_task_by_pid(pid);
-       if (!p)
-               goto out;
-       task_lock(p);
-       files = p->files;
-       if(files) {
-               spin_lock(&files->file_lock);
-               for (i=0; i < files->max_fds; i++) {
-                       if (fcheck_files(files, i) ==
-                           skb->sk->sk_socket->file) {
-                               spin_unlock(&files->file_lock);
-                               task_unlock(p);
-                               read_unlock(&tasklist_lock);
-                               return 1;
-                       }
-               }
-               spin_unlock(&files->file_lock);
-       }
-       task_unlock(p);
-out:
-       read_unlock(&tasklist_lock);
-       return 0;
-}
-
-static int
-match_sid(const struct sk_buff *skb, pid_t sid)
-{
-       struct task_struct *g, *p;
-       struct file *file = skb->sk->sk_socket->file;
-       int i, found=0;
-
-       read_lock(&tasklist_lock);
-       do_each_thread(g, p) {
-               struct files_struct *files;
-               if (p->signal->session != sid)
-                       continue;
-
-               task_lock(p);
-               files = p->files;
-               if (files) {
-                       spin_lock(&files->file_lock);
-                       for (i=0; i < files->max_fds; i++) {
-                               if (fcheck_files(files, i) == file) {
-                                       found = 1;
-                                       break;
-                               }
-                       }
-                       spin_unlock(&files->file_lock);
-               }
-               task_unlock(p);
-               if (found)
-                       goto out;
-       } while_each_thread(g, p);
-out:
-       read_unlock(&tasklist_lock);
-
-       return found;
-}
-
-static int
 match(const struct sk_buff *skb,
       const struct net_device *in,
       const struct net_device *out,
@@ -145,24 +45,6 @@ match(const struct sk_buff *skb,
                        return 0;
        }
 
-       if(info->match & IPT_OWNER_PID) {
-               if (!match_pid(skb, info->pid) ^
-                   !!(info->invert & IPT_OWNER_PID))
-                       return 0;
-       }
-
-       if(info->match & IPT_OWNER_SID) {
-               if (!match_sid(skb, info->sid) ^
-                   !!(info->invert & IPT_OWNER_SID))
-                       return 0;
-       }
-
-       if(info->match & IPT_OWNER_COMM) {
-               if (!match_comm(skb, info->comm) ^
-                   !!(info->invert & IPT_OWNER_COMM))
-                       return 0;
-       }
-
        return 1;
 }
 
@@ -173,6 +55,8 @@ checkentry(const char *tablename,
            unsigned int matchsize,
            unsigned int hook_mask)
 {
+       const struct ipt_owner_info *info = matchinfo;
+
         if (hook_mask
             & ~((1 << NF_IP_LOCAL_OUT) | (1 << NF_IP_POST_ROUTING))) {
                 printk("ipt_owner: only valid for LOCAL_OUT or POST_ROUTING.\n");
@@ -184,15 +68,13 @@ checkentry(const char *tablename,
                       IPT_ALIGN(sizeof(struct ipt_owner_info)));
                return 0;
        }
-#ifdef CONFIG_SMP
-       /* files->file_lock can not be used in a BH */
-       if (((struct ipt_owner_info *)matchinfo)->match
-           & (IPT_OWNER_PID|IPT_OWNER_SID|IPT_OWNER_COMM)) {
-               printk("ipt_owner: pid, sid and command matching is broken "
-                      "on SMP.\n");
+
+       if (info->match & (IPT_OWNER_PID|IPT_OWNER_SID|IPT_OWNER_COMM)) {
+               printk("ipt_owner: pid, sid and command matching "
+                      "not supported anymore\n");
                return 0;
        }
-#endif
+
        return 1;
 }
 
index ab0e32d..9b91dec 100644 (file)
@@ -20,71 +20,6 @@ MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
 MODULE_DESCRIPTION("IP6 tables owner matching module");
 MODULE_LICENSE("GPL");
 
-static int
-match_pid(const struct sk_buff *skb, pid_t pid)
-{
-       struct task_struct *p;
-       struct files_struct *files;
-       int i;
-
-       read_lock(&tasklist_lock);
-       p = find_task_by_pid(pid);
-       if (!p)
-               goto out;
-       task_lock(p);
-       files = p->files;
-       if(files) {
-               spin_lock(&files->file_lock);
-               for (i=0; i < files->max_fds; i++) {
-                       if (fcheck_files(files, i) == skb->sk->sk_socket->file) {
-                               spin_unlock(&files->file_lock);
-                               task_unlock(p);
-                               read_unlock(&tasklist_lock);
-                               return 1;
-                       }
-               }
-               spin_unlock(&files->file_lock);
-       }
-       task_unlock(p);
-out:
-       read_unlock(&tasklist_lock);
-       return 0;
-}
-
-static int
-match_sid(const struct sk_buff *skb, pid_t sid)
-{
-       struct task_struct *g, *p;
-       struct file *file = skb->sk->sk_socket->file;
-       int i, found=0;
-
-       read_lock(&tasklist_lock);
-       do_each_thread(g, p) {
-               struct files_struct *files;
-               if (p->signal->session != sid)
-                       continue;
-
-               task_lock(p);
-               files = p->files;
-               if (files) {
-                       spin_lock(&files->file_lock);
-                       for (i=0; i < files->max_fds; i++) {
-                               if (fcheck_files(files, i) == file) {
-                                       found = 1;
-                                       break;
-                               }
-                       }
-                       spin_unlock(&files->file_lock);
-               }
-               task_unlock(p);
-               if (found)
-                       goto out;
-       } while_each_thread(g, p);
-out:
-       read_unlock(&tasklist_lock);
-
-       return found;
-}
 
 static int
 match(const struct sk_buff *skb,
@@ -112,18 +47,6 @@ match(const struct sk_buff *skb,
                        return 0;
        }
 
-       if(info->match & IP6T_OWNER_PID) {
-               if (!match_pid(skb, info->pid) ^
-                   !!(info->invert & IP6T_OWNER_PID))
-                       return 0;
-       }
-
-       if(info->match & IP6T_OWNER_SID) {
-               if (!match_sid(skb, info->sid) ^
-                   !!(info->invert & IP6T_OWNER_SID))
-                       return 0;
-       }
-
        return 1;
 }
 
@@ -134,6 +57,8 @@ checkentry(const char *tablename,
            unsigned int matchsize,
            unsigned int hook_mask)
 {
+       const struct ip6t_owner_info *info = matchinfo;
+
         if (hook_mask
             & ~((1 << NF_IP6_LOCAL_OUT) | (1 << NF_IP6_POST_ROUTING))) {
                 printk("ip6t_owner: only valid for LOCAL_OUT or POST_ROUTING.\n");
@@ -142,14 +67,13 @@ checkentry(const char *tablename,
 
        if (matchsize != IP6T_ALIGN(sizeof(struct ip6t_owner_info)))
                return 0;
-#ifdef CONFIG_SMP
-       /* files->file_lock can not be used in a BH */
-       if (((struct ip6t_owner_info *)matchinfo)->match
-           & (IP6T_OWNER_PID|IP6T_OWNER_SID)) {
-               printk("ip6t_owner: pid and sid matching is broken on SMP.\n");
+
+       if (info->match & (IP6T_OWNER_PID|IP6T_OWNER_SID)) {
+               printk("ipt_owner: pid and sid matching "
+                      "not supported anymore\n");
                return 0;
        }
-#endif
+
        return 1;
 }