Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro:
 "A nasty bug in fs/namespace.c caught by Andrey + a couple of less
  serious unpleasantness - ecryptfs misc device playing hopeless games
  with try_module_get() and palinfo procfs support being...  not quite
  correctly done, to be polite."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mnt: release locks on error path in do_loopback
  palinfo fixes
  procfs: add proc_remove_subtree()
  ecryptfs: close rmmod race

diff --git a/arch/ia64/kernel/palinfo.c b/arch/ia64/kernel/palinfo.c
index 77597e5ea60aca9429f29c26ec7973bf89a19683..79521d5499f94e906c7a0fece9cfe206d7629c79 100644 (file)
--- a/arch/ia64/kernel/palinfo.c
+++ b/arch/ia64/kernel/palinfo.c
@@ -849,17 +849,6 @@ static palinfo_entry_t palinfo_entries[]={
 
 #define NR_PALINFO_ENTRIES     (int) ARRAY_SIZE(palinfo_entries)
 
-/*
- * this array is used to keep track of the proc entries we create. This is
- * required in the module mode when we need to remove all entries. The procfs code
- * does not do recursion of deletion
- *
- * Notes:
- *     - +1 accounts for the cpuN directory entry in /proc/pal
- */
-#define NR_PALINFO_PROC_ENTRIES        (NR_CPUS*(NR_PALINFO_ENTRIES+1))
-
-static struct proc_dir_entry *palinfo_proc_entries[NR_PALINFO_PROC_ENTRIES];
 static struct proc_dir_entry *palinfo_dir;
 
 /*
@@ -971,60 +960,32 @@ palinfo_read_entry(char *page, char **start, off_t off, int count, int *eof, voi
 static void __cpuinit
 create_palinfo_proc_entries(unsigned int cpu)
 {
-#      define CPUSTR   "cpu%d"
-
        pal_func_cpu_u_t f;
-       struct proc_dir_entry **pdir;
        struct proc_dir_entry *cpu_dir;
        int j;
-       char cpustr[sizeof(CPUSTR)];
-
-
-       /*
-        * we keep track of created entries in a depth-first order for
-        * cleanup purposes. Each entry is stored into palinfo_proc_entries
-        */
-       sprintf(cpustr,CPUSTR, cpu);
+       char cpustr[3+4+1];     /* cpu numbers are up to 4095 on itanic */
+       sprintf(cpustr, "cpu%d", cpu);
 
        cpu_dir = proc_mkdir(cpustr, palinfo_dir);
+       if (!cpu_dir)
+               return;
 
        f.req_cpu = cpu;
 
-       /*
-        * Compute the location to store per cpu entries
-        * We dont store the top level entry in this list, but
-        * remove it finally after removing all cpu entries.
-        */
-       pdir = &palinfo_proc_entries[cpu*(NR_PALINFO_ENTRIES+1)];
-       *pdir++ = cpu_dir;
        for (j=0; j < NR_PALINFO_ENTRIES; j++) {
                f.func_id = j;
-               *pdir = create_proc_read_entry(
-                               palinfo_entries[j].name, 0, cpu_dir,
-                               palinfo_read_entry, (void *)f.value);
-               pdir++;
+               create_proc_read_entry(
+                       palinfo_entries[j].name, 0, cpu_dir,
+                       palinfo_read_entry, (void *)f.value);
        }
 }
 
 static void
 remove_palinfo_proc_entries(unsigned int hcpu)
 {
-       int j;
-       struct proc_dir_entry *cpu_dir, **pdir;
-
-       pdir = &palinfo_proc_entries[hcpu*(NR_PALINFO_ENTRIES+1)];
-       cpu_dir = *pdir;
-       *pdir++=NULL;
-       for (j=0; j < (NR_PALINFO_ENTRIES); j++) {
-               if ((*pdir)) {
-                       remove_proc_entry ((*pdir)->name, cpu_dir);
-                       *pdir ++= NULL;
-               }
-       }
-
-       if (cpu_dir) {
-               remove_proc_entry(cpu_dir->name, palinfo_dir);
-       }
+       char cpustr[3+4+1];     /* cpu numbers are up to 4095 on itanic */
+       sprintf(cpustr, "cpu%d", hcpu);
+       remove_proc_subtree(cpustr, palinfo_dir);
 }
 
 static int __cpuinit palinfo_cpu_callback(struct notifier_block *nfb,
@@ -1058,6 +1019,8 @@ palinfo_init(void)
 
        printk(KERN_INFO "PAL Information Facility v%s\n", PALINFO_VERSION);
        palinfo_dir = proc_mkdir("pal", NULL);
+       if (!palinfo_dir)
+               return -ENOMEM;
 
        /* Create palinfo dirs in /proc for all online cpus */
        for_each_online_cpu(i) {
@@ -1073,22 +1036,8 @@ palinfo_init(void)
 static void __exit
 palinfo_exit(void)
 {
-       int i = 0;
-
-       /* remove all nodes: depth first pass. Could optimize this  */
-       for_each_online_cpu(i) {
-               remove_palinfo_proc_entries(i);
-       }
-
-       /*
-        * Remove the top level entry finally
-        */
-       remove_proc_entry(palinfo_dir->name, NULL);
-
-       /*
-        * Unregister from cpu notifier callbacks
-        */
        unregister_hotcpu_notifier(&palinfo_cpu_notifier);
+       remove_proc_subtree("pal", NULL);
 }
 
 module_init(palinfo_init);

diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
index 412e6eda25f813e037f3d18936e7ed860793a443..e4141f2574953893377939f2362a673a62a609b9 100644 (file)
--- a/fs/ecryptfs/miscdev.c
+++ b/fs/ecryptfs/miscdev.c
@@ -80,13 +80,6 @@ ecryptfs_miscdev_open(struct inode *inode, struct file *file)
        int rc;
 
        mutex_lock(&ecryptfs_daemon_hash_mux);
-       rc = try_module_get(THIS_MODULE);
-       if (rc == 0) {
-               rc = -EIO;
-               printk(KERN_ERR "%s: Error attempting to increment module use "
-                      "count; rc = [%d]\n", __func__, rc);
-               goto out_unlock_daemon_list;
-       }
        rc = ecryptfs_find_daemon_by_euid(&daemon);
        if (!rc) {
                rc = -EINVAL;
@@ -96,7 +89,7 @@ ecryptfs_miscdev_open(struct inode *inode, struct file *file)
        if (rc) {
                printk(KERN_ERR "%s: Error attempting to spawn daemon; "
                       "rc = [%d]\n", __func__, rc);
-               goto out_module_put_unlock_daemon_list;
+               goto out_unlock_daemon_list;
        }
        mutex_lock(&daemon->mux);
        if (daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN) {
@@ -108,9 +101,6 @@ ecryptfs_miscdev_open(struct inode *inode, struct file *file)
        atomic_inc(&ecryptfs_num_miscdev_opens);
 out_unlock_daemon:
        mutex_unlock(&daemon->mux);
-out_module_put_unlock_daemon_list:
-       if (rc)
-               module_put(THIS_MODULE);
 out_unlock_daemon_list:
        mutex_unlock(&ecryptfs_daemon_hash_mux);
        return rc;
@@ -147,7 +137,6 @@ ecryptfs_miscdev_release(struct inode *inode, struct file *file)
                       "bug.\n", __func__, rc);
                BUG();
        }
-       module_put(THIS_MODULE);
        return rc;
 }
 
@@ -471,6 +460,7 @@ out_free:
 
 
 static const struct file_operations ecryptfs_miscdev_fops = {
+       .owner   = THIS_MODULE,
        .open    = ecryptfs_miscdev_open,
        .poll    = ecryptfs_miscdev_poll,
        .read    = ecryptfs_miscdev_read,

diff --git a/fs/namespace.c b/fs/namespace.c
index d581e45c0a9fd6ada94edd2bb6ea4fe4c7fc9e23..341d3f564082f2367a7f1538255e90bdfbfd8cd2 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1690,7 +1690,7 @@ static int do_loopback(struct path *path, const char *old_name,
 
        if (IS_ERR(mnt)) {
                err = PTR_ERR(mnt);
-               goto out;
+               goto out2;
        }
 
        err = graft_tree(mnt, path);

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 4b3b3ffb52f14e234aa3ec99abde281ca41e1817..21e1a8f1659d097f455e196d0b775771d3904b2b 100644 (file)
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -755,37 +755,8 @@ void pde_put(struct proc_dir_entry *pde)
                free_proc_entry(pde);
 }
 
-/*
- * Remove a /proc entry and free it if it's not currently in use.
- */
-void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+static void entry_rundown(struct proc_dir_entry *de)
 {
-       struct proc_dir_entry **p;
-       struct proc_dir_entry *de = NULL;
-       const char *fn = name;
-       unsigned int len;
-
-       spin_lock(&proc_subdir_lock);
-       if (__xlate_proc_name(name, &parent, &fn) != 0) {
-               spin_unlock(&proc_subdir_lock);
-               return;
-       }
-       len = strlen(fn);
-
-       for (p = &parent->subdir; *p; p=&(*p)->next ) {
-               if (proc_match(len, fn, *p)) {
-                       de = *p;
-                       *p = de->next;
-                       de->next = NULL;
-                       break;
-               }
-       }
-       spin_unlock(&proc_subdir_lock);
-       if (!de) {
-               WARN(1, "name '%s'\n", name);
-               return;
-       }
-
        spin_lock(&de->pde_unload_lock);
        /*
         * Stop accepting new callers into module. If you're
@@ -817,6 +788,40 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
                spin_lock(&de->pde_unload_lock);
        }
        spin_unlock(&de->pde_unload_lock);
+}
+
+/*
+ * Remove a /proc entry and free it if it's not currently in use.
+ */
+void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+{
+       struct proc_dir_entry **p;
+       struct proc_dir_entry *de = NULL;
+       const char *fn = name;
+       unsigned int len;
+
+       spin_lock(&proc_subdir_lock);
+       if (__xlate_proc_name(name, &parent, &fn) != 0) {
+               spin_unlock(&proc_subdir_lock);
+               return;
+       }
+       len = strlen(fn);
+
+       for (p = &parent->subdir; *p; p=&(*p)->next ) {
+               if (proc_match(len, fn, *p)) {
+                       de = *p;
+                       *p = de->next;
+                       de->next = NULL;
+                       break;
+               }
+       }
+       spin_unlock(&proc_subdir_lock);
+       if (!de) {
+               WARN(1, "name '%s'\n", name);
+               return;
+       }
+
+       entry_rundown(de);
 
        if (S_ISDIR(de->mode))
                parent->nlink--;
@@ -827,3 +832,57 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
        pde_put(de);
 }
 EXPORT_SYMBOL(remove_proc_entry);
+
+int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
+{
+       struct proc_dir_entry **p;
+       struct proc_dir_entry *root = NULL, *de, *next;
+       const char *fn = name;
+       unsigned int len;
+
+       spin_lock(&proc_subdir_lock);
+       if (__xlate_proc_name(name, &parent, &fn) != 0) {
+               spin_unlock(&proc_subdir_lock);
+               return -ENOENT;
+       }
+       len = strlen(fn);
+
+       for (p = &parent->subdir; *p; p=&(*p)->next ) {
+               if (proc_match(len, fn, *p)) {
+                       root = *p;
+                       *p = root->next;
+                       root->next = NULL;
+                       break;
+               }
+       }
+       if (!root) {
+               spin_unlock(&proc_subdir_lock);
+               return -ENOENT;
+       }
+       de = root;
+       while (1) {
+               next = de->subdir;
+               if (next) {
+                       de->subdir = next->next;
+                       next->next = NULL;
+                       de = next;
+                       continue;
+               }
+               spin_unlock(&proc_subdir_lock);
+
+               entry_rundown(de);
+               next = de->parent;
+               if (S_ISDIR(de->mode))
+                       next->nlink--;
+               de->nlink = 0;
+               if (de == root)
+                       break;
+               pde_put(de);
+
+               spin_lock(&proc_subdir_lock);
+               de = next;
+       }
+       pde_put(root);
+       return 0;
+}
+EXPORT_SYMBOL(remove_proc_subtree);

diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 8307f2f94d860f46139b6a20d6795a9186704c19..94dfb2aa5533c3c6a2a661358a6da4c6555310d3 100644 (file)
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -117,6 +117,7 @@ struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
                                const struct file_operations *proc_fops,
                                void *data);
 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
+extern int remove_proc_subtree(const char *name, struct proc_dir_entry *parent);
 
 struct pid_namespace;
 
@@ -202,6 +203,7 @@ static inline struct proc_dir_entry *proc_create_data(const char *name,
        return NULL;
 }
 #define remove_proc_entry(name, parent) do {} while (0)
+#define remove_proc_subtree(name, parent) do {} while (0)
 
 static inline struct proc_dir_entry *proc_symlink(const char *name,
                struct proc_dir_entry *parent,const char *dest) {return NULL;}