fix

diff --git a/ChangeLog b/ChangeLog
index 94327f4f68f0badf160f91441db360597c7a713a..541580319a572e6ff9aaf31f0ce6e120a0f86608 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,12 @@
        * Fix buggy behavior of open(..., O_CREAT|O_EXCL) if interrupted.
        Reported by David Shaw
 
+       * Remove "allow_root" option from kernel module, and implement
+       it's functionality in the library
+
+       * Fix Oops caused by premature release of fuse_conn.  Clean up
+       related code, to be more readable
+
 2005-04-08  Miklos Szeredi <miklos@szeredi.hu>
 
        * Fix Oops in case of nfs export.  Spotted by David Shaw

diff --git a/kernel/dev.c b/kernel/dev.c
index 29a9b6366139295df36c648a9eb9c84c570e5e90..d64423e1e44667019c266cd12796a2c03e7364fd 100644 (file)
--- a/kernel/dev.c
+++ b/kernel/dev.c
@@ -24,7 +24,7 @@ static inline struct fuse_conn *fuse_get_conn(struct file *file)
        struct fuse_conn *fc;
        spin_lock(&fuse_lock);
        fc = file->private_data;
-       if (fc && !fc->sb)
+       if (fc && !fc->mounted)
                fc = NULL;
        spin_unlock(&fuse_lock);
        return fc;
@@ -214,7 +214,7 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req)
        spin_unlock(&fuse_lock);
        if (req->background) {
                down_read(&fc->sbput_sem);
-               if (fc->sb)
+               if (fc->mounted)
                        fuse_release_background(req);
                up_read(&fc->sbput_sem);
        }
@@ -371,7 +371,7 @@ static void request_send_wait(struct fuse_conn *fc, struct fuse_req *req,
 {
        req->isreply = 1;
        spin_lock(&fuse_lock);
-       if (!fc->file)
+       if (!fc->connected)
                req->out.h.error = -ENOTCONN;
        else if (fc->conn_error)
                req->out.h.error = -ECONNREFUSED;
@@ -404,7 +404,7 @@ void request_send_nonint(struct fuse_conn *fc, struct fuse_req *req)
 static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
 {
        spin_lock(&fuse_lock);
-       if (fc->file) {
+       if (fc->connected) {
                queue_request(fc, req);
                spin_unlock(&fuse_lock);
        } else {
@@ -659,7 +659,7 @@ static void request_wait(struct fuse_conn *fc)
        DECLARE_WAITQUEUE(wait, current);
 
        add_wait_queue_exclusive(&fc->waitq, &wait);
-       while (fc->sb && list_empty(&fc->pending)) {
+       while (fc->mounted && list_empty(&fc->pending)) {
                set_current_state(TASK_INTERRUPTIBLE);
                if (signal_pending(current))
                        break;
@@ -709,7 +709,7 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov,
                goto err_unlock;
        request_wait(fc);
        err = -ENODEV;
-       if (!fc->sb)
+       if (!fc->mounted)
                goto err_unlock;
        err = -ERESTARTSYS;
        if (list_empty(&fc->pending))
@@ -917,7 +917,7 @@ static int fuse_dev_release(struct inode *inode, struct file *file)
        spin_lock(&fuse_lock);
        fc = file->private_data;
        if (fc) {
-               fc->file = NULL;
+               fc->connected = 0;
                end_requests(fc, &fc->pending);
                end_requests(fc, &fc->processing);
                fuse_release_conn(fc);

diff --git a/kernel/dir.c b/kernel/dir.c
index 6ae498cfd885cff2137dd7a46837ea56d5c4c1fc..947d5386149da4a5eb6d4e5ef2ff73f1b44066d7 100644 (file)
--- a/kernel/dir.c
+++ b/kernel/dir.c
@@ -441,9 +441,7 @@ static int fuse_revalidate(struct dentry *entry)
 
        if (get_node_id(inode) == FUSE_ROOT_ID) {
                if (!(fc->flags & FUSE_ALLOW_OTHER) &&
-                   current->fsuid != fc->user_id &&
-                   (!(fc->flags & FUSE_ALLOW_ROOT) ||
-                    !capable(CAP_DAC_OVERRIDE)))
+                   current->fsuid != fc->user_id)
                        return -EACCES;
        } else if (time_before_eq(jiffies, fi->i_time))
                return 0;
@@ -455,8 +453,7 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
 {
        struct fuse_conn *fc = get_fuse_conn(inode);
 
-       if (!(fc->flags & FUSE_ALLOW_OTHER) && current->fsuid != fc->user_id &&
-           (!(fc->flags & FUSE_ALLOW_ROOT) || !capable(CAP_DAC_OVERRIDE)))
+       if (!(fc->flags & FUSE_ALLOW_OTHER) && current->fsuid != fc->user_id)
                return -EACCES;
        else if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
 #ifdef KERNEL_2_6_10_PLUS

diff --git a/kernel/fuse_i.h b/kernel/fuse_i.h
index 373f36dd821fdc3db893421d53932142bdfeee15..164eaa7f0d58b8a6b658b864fe435b7a52e61cd4 100644 (file)
--- a/kernel/fuse_i.h
+++ b/kernel/fuse_i.h
@@ -101,10 +101,6 @@ static inline void set_page_dirty_lock(struct page *page)
 /** Bypass the page cache for read and write operations  */
 #define FUSE_DIRECT_IO           (1 << 3)
 
-/** Allow root and setuid-root programs to access fuse-mounted
-    filesystems */
-#define FUSE_ALLOW_ROOT                 (1 << 4)
-
 /** FUSE inode */
 struct fuse_inode {
        /** Inode data */
@@ -260,11 +256,8 @@ struct fuse_req {
  * unmounted.
  */
 struct fuse_conn {
-       /** The superblock of the mounted filesystem */
-       struct super_block *sb;
-
-       /** The opened client device */
-       struct file *file;
+       /** Reference count */
+       int count;
 
        /** The user id for this mount */
        uid_t user_id;
@@ -307,6 +300,12 @@ struct fuse_conn {
        /** The next unique request id */
        int reqctr;
 
+       /** Mount is active */
+       unsigned mounted : 1;
+
+       /** Connection established */
+       unsigned connected : 1;
+
        /** Connection failed (version mismatch) */
        unsigned conn_error : 1;
 

diff --git a/kernel/inode.c b/kernel/inode.c
index 1feaba9ab1bb6251b5d63938245863f327242d02..9b894f5d9b46ee4e39b5427ad15abbb50d39be33 100644 (file)
--- a/kernel/inode.c
+++ b/kernel/inode.c
@@ -99,8 +99,8 @@ void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
 
 static void fuse_clear_inode(struct inode *inode)
 {
-       struct fuse_conn *fc = get_fuse_conn(inode);
-       if (fc && (inode->i_sb->s_flags & MS_ACTIVE)) {
+       if (inode->i_sb->s_flags & MS_ACTIVE) {
+               struct fuse_conn *fc = get_fuse_conn(inode);
                struct fuse_inode *fi = get_fuse_inode(inode);
                fuse_send_forget(fc, fi->forget_req, fi->nodeid, inode->i_version);
                fi->forget_req = NULL;
@@ -260,14 +260,13 @@ static void fuse_put_super(struct super_block *sb)
                                                   struct fuse_req, bg_entry));
 
        spin_lock(&fuse_lock);
-       fc->sb = NULL;
+       fc->mounted = 0;
        fc->user_id = 0;
        fc->flags = 0;
        /* Flush all readers on this fs */
        wake_up_all(&fc->waitq);
        up_write(&fc->sbput_sem);
        fuse_release_conn(fc);
-       *get_fuse_conn_super_p(sb) = NULL;
        spin_unlock(&fuse_lock);
 }
 
@@ -314,7 +313,6 @@ enum {
        OPT_USER_ID,
        OPT_DEFAULT_PERMISSIONS,
        OPT_ALLOW_OTHER,
-       OPT_ALLOW_ROOT,
        OPT_KERNEL_CACHE,
 #ifndef KERNEL_2_6
        OPT_LARGE_READ,
@@ -330,7 +328,6 @@ static match_table_t tokens = {
        {OPT_USER_ID,                   "user_id=%u"},
        {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
        {OPT_ALLOW_OTHER,               "allow_other"},
-       {OPT_ALLOW_ROOT,                "allow_root"},
        {OPT_KERNEL_CACHE,              "kernel_cache"},
 #ifndef KERNEL_2_6
        {OPT_LARGE_READ,                "large_read"},
@@ -382,10 +379,6 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d)
                        d->flags |= FUSE_ALLOW_OTHER;
                        break;
 
-               case OPT_ALLOW_ROOT:
-                       d->flags |= FUSE_ALLOW_ROOT;
-                       break;
-
                case OPT_KERNEL_CACHE:
                        d->flags |= FUSE_KERNEL_CACHE;
                        break;
@@ -424,8 +417,6 @@ static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
                seq_puts(m, ",default_permissions");
        if (fc->flags & FUSE_ALLOW_OTHER)
                seq_puts(m, ",allow_other");
-       if (fc->flags & FUSE_ALLOW_ROOT)
-               seq_puts(m, ",allow_root");
        if (fc->flags & FUSE_KERNEL_CACHE)
                seq_puts(m, ",kernel_cache");
 #ifndef KERNEL_2_6
@@ -453,7 +444,8 @@ static void free_conn(struct fuse_conn *fc)
 /* Must be called with the fuse lock held */
 void fuse_release_conn(struct fuse_conn *fc)
 {
-       if (!fc->sb && !fc->file)
+       fc->count--;
+       if (!fc->count)
                free_conn(fc);
 }
 
@@ -465,10 +457,6 @@ static struct fuse_conn *new_conn(void)
        if (fc != NULL) {
                int i;
                memset(fc, 0, sizeof(*fc));
-               fc->sb = NULL;
-               fc->file = NULL;
-               fc->flags = 0;
-               fc->user_id = 0;
                init_waitqueue_head(&fc->waitq);
                INIT_LIST_HEAD(&fc->pending);
                INIT_LIST_HEAD(&fc->processing);
@@ -508,8 +496,10 @@ static struct fuse_conn *get_conn(struct file *file, struct super_block *sb)
                fc = ERR_PTR(-EINVAL);
        } else {
                file->private_data = fc;
-               fc->sb = sb;
-               fc->file = file;
+               *get_fuse_conn_super_p(sb) = fc;
+               fc->mounted = 1;
+               fc->connected = 1;
+               fc->count = 2;
        }
        spin_unlock(&fuse_lock);
        return fc;
@@ -636,8 +626,6 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 #endif
        fc->max_write = FUSE_MAX_IN / 2;
 
-       *get_fuse_conn_super_p(sb) = fc;
-
        err = -ENOMEM;
        root = get_root_inode(sb, d.rootmode);
        if (root == NULL)
@@ -653,10 +641,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 
  err:
        spin_lock(&fuse_lock);
-       fc->sb = NULL;
        fuse_release_conn(fc);
        spin_unlock(&fuse_lock);
-       *get_fuse_conn_super_p(sb) = NULL;
        return err;
 }
 

diff --git a/lib/fuse.c b/lib/fuse.c
index 82adeb274d43fac9c5bbb596cd1a69ec4141a1cd..9659a0d29ffa572650444fb1b4878e609a821b9d 100644 (file)
--- a/lib/fuse.c
+++ b/lib/fuse.c
@@ -35,6 +35,9 @@
 /** Use st_ino field in getattr instead of generating inode numbers  */
 #define FUSE_USE_INO     (1 << 3)
 
+/** Only allow root or the owner to access the filesystem */
+#define FUSE_ALLOW_ROOT  (1 << 4)
+
 #define FUSE_KERNEL_MINOR_VERSION_NEED 1
 #define FUSE_VERSION_FILE_OLD "/proc/fs/fuse/version"
 #define FUSE_VERSION_FILE_NEW "/sys/fs/fuse/version"
@@ -1765,6 +1768,15 @@ void fuse_process_cmd(struct fuse *f, struct fuse_cmd *cmd)
         goto out;
     }
 
+    if ((f->flags & FUSE_ALLOW_ROOT) && in->uid != f->owner && in->uid != 0 &&
+        in->opcode != FUSE_INIT && in->opcode != FUSE_READ &&
+        in->opcode != FUSE_WRITE && in->opcode != FUSE_FSYNC && 
+        in->opcode != FUSE_RELEASE && in->opcode != FUSE_READDIR &&
+        in->opcode != FUSE_FSYNCDIR && in->opcode != FUSE_RELEASEDIR) {
+        send_reply(f, in, -EACCES, NULL, 0);
+        goto out;
+    }
+
     ctx->fuse = f;
     ctx->uid = in->uid;
     ctx->gid = in->gid;
@@ -2000,7 +2012,8 @@ int fuse_is_lib_option(const char *opt)
 {
     if (strcmp(opt, "debug") == 0 ||
         strcmp(opt, "hard_remove") == 0 ||
-        strcmp(opt, "use_ino") == 0)
+        strcmp(opt, "use_ino") == 0 ||
+        strcmp(opt, "allow_root") == 0)
         return 1;
     else
         return 0;
@@ -2025,6 +2038,8 @@ static int parse_lib_opts(struct fuse *f, const char *opts)
                 f->flags |= FUSE_HARD_REMOVE;
             else if (strcmp(opt, "use_ino") == 0)
                 f->flags |= FUSE_USE_INO;
+            else if (strcmp(opt, "allow_root") == 0)
+                f->flags |= FUSE_ALLOW_ROOT;
             else
                 fprintf(stderr, "fuse: warning: unknown option `%s'\n", opt);
         }
@@ -2100,6 +2115,8 @@ struct fuse *fuse_new_common(int fd, const char *opts,
     root->refctr = 1;
     hash_id(f, root);
 
+    f->owner = getuid();
+
     return f;
 
  out_free_root:

diff --git a/lib/fuse_i.h b/lib/fuse_i.h
index 4a9f04ad8a9e4c4c16d5196ca644ebc81fe65b5e..3bdfb00a7fea96f8937fda78b7e040ef39f329b3 100644 (file)
--- a/lib/fuse_i.h
+++ b/lib/fuse_i.h
@@ -32,6 +32,7 @@ struct fuse {
     void *user_data;
     int major;
     int minor;
+    uid_t owner;
 };
 
 struct fuse *fuse_new_common(int fd, const char *opts,

diff --git a/lib/helper.c b/lib/helper.c
index 42fe44caee8a28fd2c149c5e255ba7377a377eaa..d1a3d1faab335f2187d138b03dae6bb92f0a988b 100644 (file)
--- a/lib/helper.c
+++ b/lib/helper.c
@@ -138,8 +138,12 @@ static int add_options(char **lib_optp, char **kernel_optp, const char *opts)
 
     while((opt = strsep(&s, ",")) != NULL) {
         int res;
-        if (fuse_is_lib_option(opt))
+        if (fuse_is_lib_option(opt)) {
             res = add_option_to(opt, lib_optp);
+            /* Compatibility hack */
+            if (strcmp(opt, "allow_root") == 0 && res != -1)
+                res = add_option_to("allow_other", kernel_optp);
+        }
         else
             res = add_option_to(opt, kernel_optp);
         if (res == -1) {