Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / net / ax25 / ax25_uid.c

diff --git a/net/ax25/ax25_uid.c b/net/ax25/ax25_uid.c
index cea6b7d..5e9a81e 100644 (file)
--- a/net/ax25/ax25_uid.c
+++ b/net/ax25/ax25_uid.c
@@ -6,6 +6,8 @@
  *
  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
  */
+
+#include <linux/capability.h>
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/socket.h>
@@ -28,6 +30,7 @@
 #include <linux/fcntl.h>
 #include <linux/mm.h>
 #include <linux/interrupt.h>
+#include <linux/list.h>
 #include <linux/notifier.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
@@ -41,38 +44,45 @@
  *     Callsign/UID mapper. This is in kernel space for security on multi-amateur machines.
  */
 
-static ax25_uid_assoc *ax25_uid_list;
+HLIST_HEAD(ax25_uid_list);
 static DEFINE_RWLOCK(ax25_uid_lock);
 
 int ax25_uid_policy = 0;
 
-ax25_address *ax25_findbyuid(uid_t uid)
+EXPORT_SYMBOL(ax25_uid_policy);
+
+ax25_uid_assoc *ax25_findbyuid(uid_t uid)
 {
-       ax25_uid_assoc *ax25_uid;
-       ax25_address *res = NULL;
+       ax25_uid_assoc *ax25_uid, *res = NULL;
+       struct hlist_node *node;
 
        read_lock(&ax25_uid_lock);
-       for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
+       ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
                if (ax25_uid->uid == uid) {
-                       res = &ax25_uid->call;
+                       ax25_uid_hold(ax25_uid);
+                       res = ax25_uid;
                        break;
                }
        }
        read_unlock(&ax25_uid_lock);
 
-       return NULL;
+       return res;
 }
 
+EXPORT_SYMBOL(ax25_findbyuid);
+
 int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
 {
-       ax25_uid_assoc *s, *ax25_uid;
+       ax25_uid_assoc *ax25_uid;
+       struct hlist_node *node;
+       ax25_uid_assoc *user;
        unsigned long res;
 
        switch (cmd) {
        case SIOCAX25GETUID:
                res = -ENOENT;
                read_lock(&ax25_uid_lock);
-               for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
+               ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
                        if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
                                res = ax25_uid->uid;
                                break;
@@ -85,19 +95,22 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
        case SIOCAX25ADDUID:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
-               if (ax25_findbyuid(sax->sax25_uid))
+               user = ax25_findbyuid(sax->sax25_uid);
+               if (user) {
+                       ax25_uid_put(user);
                        return -EEXIST;
+               }
                if (sax->sax25_uid == 0)
                        return -EINVAL;
                if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
                        return -ENOMEM;
 
+               atomic_set(&ax25_uid->refcount, 1);
                ax25_uid->uid  = sax->sax25_uid;
                ax25_uid->call = sax->sax25_call;
 
                write_lock(&ax25_uid_lock);
-               ax25_uid->next = ax25_uid_list;
-               ax25_uid_list  = ax25_uid;
+               hlist_add_head(&ax25_uid->uid_node, &ax25_uid_list);
                write_unlock(&ax25_uid_lock);
 
                return 0;
@@ -106,34 +119,21 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
 
+               ax25_uid = NULL;
                write_lock(&ax25_uid_lock);
-               for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
-                       if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
+               ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
+                       if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
                                break;
-                       }
                }
                if (ax25_uid == NULL) {
                        write_unlock(&ax25_uid_lock);
                        return -ENOENT;
                }
-               if ((s = ax25_uid_list) == ax25_uid) {
-                       ax25_uid_list = s->next;
-                       write_unlock(&ax25_uid_lock);
-                       kfree(ax25_uid);
-                       return 0;
-               }
-               while (s != NULL && s->next != NULL) {
-                       if (s->next == ax25_uid) {
-                               s->next = ax25_uid->next;
-                               write_unlock(&ax25_uid_lock);
-                               kfree(ax25_uid);
-                               return 0;
-                       }
-                       s = s->next;
-               }
+               hlist_del_init(&ax25_uid->uid_node);
+               ax25_uid_put(ax25_uid);
                write_unlock(&ax25_uid_lock);
 
-               return -ENOENT;
+               return 0;
 
        default:
                return -EINVAL;
@@ -147,13 +147,11 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
 static void *ax25_uid_seq_start(struct seq_file *seq, loff_t *pos)
 {
        struct ax25_uid_assoc *pt;
-       int i = 1;
+       struct hlist_node *node;
+       int i = 0;
 
        read_lock(&ax25_uid_lock);
-       if (*pos == 0)
-               return SEQ_START_TOKEN;
-
-       for (pt = ax25_uid_list; pt != NULL; pt = pt->next) {
+       ax25_uid_for_each(pt, node, &ax25_uid_list) {
                if (i == *pos)
                        return pt;
                ++i;
@@ -164,8 +162,9 @@ static void *ax25_uid_seq_start(struct seq_file *seq, loff_t *pos)
 static void *ax25_uid_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
        ++*pos;
-       return (v == SEQ_START_TOKEN) ? ax25_uid_list : 
-               ((struct ax25_uid_assoc *) v)->next;
+
+       return hlist_entry(((ax25_uid_assoc *)v)->uid_node.next,
+                          ax25_uid_assoc, uid_node);
 }
 
 static void ax25_uid_seq_stop(struct seq_file *seq, void *v)
@@ -175,13 +174,14 @@ static void ax25_uid_seq_stop(struct seq_file *seq, void *v)
 
 static int ax25_uid_seq_show(struct seq_file *seq, void *v)
 {
+       char buf[11];
+
        if (v == SEQ_START_TOKEN)
                seq_printf(seq, "Policy: %d\n", ax25_uid_policy);
        else {
                struct ax25_uid_assoc *pt = v;
-               
 
-               seq_printf(seq, "%6d %s\n", pt->uid, ax2asc(&pt->call));
+               seq_printf(seq, "%6d %s\n", pt->uid, ax2asc(buf, &pt->call));
        }
        return 0;
 }
@@ -213,16 +213,13 @@ struct file_operations ax25_uid_fops = {
  */
 void __exit ax25_uid_free(void)
 {
-       ax25_uid_assoc *s, *ax25_uid;
+       ax25_uid_assoc *ax25_uid;
+       struct hlist_node *node;
 
        write_lock(&ax25_uid_lock);
-       ax25_uid = ax25_uid_list;
-       while (ax25_uid != NULL) {
-               s        = ax25_uid;
-               ax25_uid = ax25_uid->next;
-
-               kfree(s);
+       ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
+               hlist_del_init(&ax25_uid->uid_node);
+               ax25_uid_put(ax25_uid);
        }
-       ax25_uid_list = NULL;
        write_unlock(&ax25_uid_lock);
 }