Merge branch 'for-linus-v3.20' of git://git.infradead.org/linux-ubifs

Pull UBI and UBIFS updates from Richard Weinberger:
 - cleanups and bug fixes all over UBI and UBIFS
 - block-mq support for UBI Block
 - UBI volumes can now be renamed while they are in use
 - security.* XATTR support for UBIFS
 - a maintainer update

* 'for-linus-v3.20' of git://git.infradead.org/linux-ubifs:
  UBI: block: Fix checking for NULL instead of IS_ERR()
  UBI: block: Continue creating ubiblocks after an initialization error
  UBIFS: return -EINVAL if log head is empty
  UBI: Block: Explain usage of blk_rq_map_sg()
  UBI: fix soft lockup in ubi_check_volume()
  UBI: Fastmap: Care about the protection queue
  UBIFS: add a couple of extra asserts
  UBI: do propagate positive error codes up
  UBI: clean-up printing helpers
  UBI: extend UBI layer debug/messaging capabilities - cosmetics
  UBIFS: add ubifs_err() to print error reason
  UBIFS: Add security.* XATTR support for the UBIFS
  UBIFS: Add xattr support for symlinks
  UBI: Block: Add blk-mq support
  UBI: Add initial support for scatter gather
  UBI: rename_volumes: Use UBI_METAONLY
  UBI: Implement UBI_METAONLY
  Add myself as UBI co-maintainer

7 files changed, 148 insertions, 12 deletions

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 7ed13e1e216a..4cfb3e82c56f 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -2032,6 +2032,8 @@ static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
                 long long blk_offs;
                 struct ubifs_data_node *dn = node;
 
+                ubifs_assert(zbr->len >= UBIFS_DATA_NODE_SZ);
+
                 /*
                  * Search the inode node this data node belongs to and insert
                  * it to the RB-tree of inodes.
@@ -2060,6 +2062,8 @@ static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
                 struct ubifs_dent_node *dent = node;
                 struct fsck_inode *fscki1;
 
+                ubifs_assert(zbr->len >= UBIFS_DENT_NODE_SZ);
+
                 err = ubifs_validate_entry(c, dent);
                 if (err)
                         goto out_dump;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index c49b1981ac95..0fa6c803992e 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -270,6 +270,10 @@ static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
                 goto out_budg;
         }
 
+        err = ubifs_init_security(dir, inode, &dentry->d_name);
+        if (err)
+                goto out_cancel;
+
         mutex_lock(&dir_ui->ui_mutex);
         dir->i_size += sz_change;
         dir_ui->ui_size = dir->i_size;
@@ -726,6 +730,10 @@ static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
                 goto out_budg;
         }
 
+        err = ubifs_init_security(dir, inode, &dentry->d_name);
+        if (err)
+                goto out_cancel;
+
         mutex_lock(&dir_ui->ui_mutex);
         insert_inode_hash(inode);
         inc_nlink(inode);
@@ -806,6 +814,10 @@ static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
         ui->data = dev;
         ui->data_len = devlen;
 
+        err = ubifs_init_security(dir, inode, &dentry->d_name);
+        if (err)
+                goto out_cancel;
+
         mutex_lock(&dir_ui->ui_mutex);
         dir->i_size += sz_change;
         dir_ui->ui_size = dir->i_size;
@@ -882,6 +894,10 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
         ui->data_len = len;
         inode->i_size = ubifs_inode(inode)->ui_size = len;
 
+        err = ubifs_init_security(dir, inode, &dentry->d_name);
+        if (err)
+                goto out_cancel;
+
         mutex_lock(&dir_ui->ui_mutex);
         dir->i_size += sz_change;
         dir_ui->ui_size = dir->i_size;
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 035e51011444..e627c0acf626 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1573,6 +1573,10 @@ const struct inode_operations ubifs_symlink_inode_operations = {
         .follow_link = ubifs_follow_link,
         .setattr     = ubifs_setattr,
         .getattr     = ubifs_getattr,
+        .setxattr    = ubifs_setxattr,
+        .getxattr    = ubifs_getxattr,
+        .listxattr   = ubifs_listxattr,
+        .removexattr = ubifs_removexattr,
 };
 
 const struct file_operations ubifs_file_operations = {
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index 3187925e9879..9b40a1c5e160 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -1028,9 +1028,22 @@ int ubifs_replay_journal(struct ubifs_info *c)
 
         do {
                 err = replay_log_leb(c, lnum, 0, c->sbuf);
-                if (err == 1)
-                        /* We hit the end of the log */
-                        break;
+                if (err == 1) {
+                        if (lnum != c->lhead_lnum)
+                                /* We hit the end of the log */
+                                break;
+
+                        /*
+                         * The head of the log must always start with the
+                         * "commit start" node on a properly formatted UBIFS.
+                         * But we found no nodes at all, which means that
+                         * someting went wrong and we cannot proceed mounting
+                         * the file-system.
+                         */
+                        ubifs_err("no UBIFS nodes found at the log head LEB %d:%d, possibly corrupted",
+                                  lnum, 0);
+                        err = -EINVAL;
+                }
                 if (err)
                         goto out;
                 lnum = ubifs_next_log_lnum(c, lnum);
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 6197154f36ca..93e946561c5c 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -2036,6 +2036,7 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
         if (c->max_inode_sz > MAX_LFS_FILESIZE)
                 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
         sb->s_op = &ubifs_super_operations;
+        sb->s_xattr = ubifs_xattr_handlers;
 
         mutex_lock(&c->umount_mutex);
         err = mount_ubifs(c);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index c4fe900c67ab..bc04b9c69891 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -36,6 +36,7 @@
 #include <linux/mtd/ubi.h>
 #include <linux/pagemap.h>
 #include <linux/backing-dev.h>
+#include <linux/security.h>
 #include "ubifs-media.h"
 
 /* Version of this UBIFS implementation */
@@ -1465,6 +1466,7 @@ extern spinlock_t ubifs_infos_lock;
 extern atomic_long_t ubifs_clean_zn_cnt;
 extern struct kmem_cache *ubifs_inode_slab;
 extern const struct super_operations ubifs_super_operations;
+extern const struct xattr_handler *ubifs_xattr_handlers[];
 extern const struct address_space_operations ubifs_file_address_operations;
 extern const struct file_operations ubifs_file_operations;
 extern const struct inode_operations ubifs_file_inode_operations;
@@ -1754,6 +1756,8 @@ ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
                        size_t size);
 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
 int ubifs_removexattr(struct dentry *dentry, const char *name);
+int ubifs_init_security(struct inode *dentry, struct inode *inode,
+                        const struct qstr *qstr);
 
 /* super.c */
 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 5e0a63b1b0d5..a92be244a6fb 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -100,24 +100,30 @@ static const struct file_operations empty_fops;
 static int create_xattr(struct ubifs_info *c, struct inode *host,
                         const struct qstr *nm, const void *value, int size)
 {
-        int err;
+        int err, names_len;
         struct inode *inode;
         struct ubifs_inode *ui, *host_ui = ubifs_inode(host);
         struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
                                 .new_ino_d = ALIGN(size, 8), .dirtied_ino = 1,
                                 .dirtied_ino_d = ALIGN(host_ui->data_len, 8) };
 
-        if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE)
+        if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE) {
+                ubifs_err("inode %lu already has too many xattrs (%d), cannot create more",
+                          host->i_ino, host_ui->xattr_cnt);
                 return -ENOSPC;
+        }
         /*
          * Linux limits the maximum size of the extended attribute names list
          * to %XATTR_LIST_MAX. This means we should not allow creating more
          * extended attributes if the name list becomes larger. This limitation
          * is artificial for UBIFS, though.
          */
-        if (host_ui->xattr_names + host_ui->xattr_cnt +
-                                        nm->len + 1 > XATTR_LIST_MAX)
+        names_len = host_ui->xattr_names + host_ui->xattr_cnt + nm->len + 1;
+        if (names_len > XATTR_LIST_MAX) {
+                ubifs_err("cannot add one more xattr name to inode %lu, total names length would become %d, max. is %d",
+                          host->i_ino, names_len, XATTR_LIST_MAX);
                 return -ENOSPC;
+        }
 
         err = ubifs_budget_space(c, &req);
         if (err)
@@ -293,18 +299,16 @@ static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
         return ERR_PTR(-EINVAL);
 }
 
-int ubifs_setxattr(struct dentry *dentry, const char *name,
-                   const void *value, size_t size, int flags)
+static int setxattr(struct inode *host, const char *name, const void *value,
+                    size_t size, int flags)
 {
-        struct inode *inode, *host = dentry->d_inode;
+        struct inode *inode;
         struct ubifs_info *c = host->i_sb->s_fs_info;
         struct qstr nm = QSTR_INIT(name, strlen(name));
         struct ubifs_dent_node *xent;
         union ubifs_key key;
         int err, type;
 
-        dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd", name,
-                host->i_ino, dentry, size);
         ubifs_assert(mutex_is_locked(&host->i_mutex));
 
         if (size > UBIFS_MAX_INO_DATA)
@@ -356,6 +360,15 @@ out_free:
         return err;
 }
 
+int ubifs_setxattr(struct dentry *dentry, const char *name,
+                   const void *value, size_t size, int flags)
+{
+        dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd",
+                name, dentry->d_inode->i_ino, dentry, size);
+
+        return setxattr(dentry->d_inode, name, value, size, flags);
+}
+
 ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
                        size_t size)
 {
@@ -568,3 +581,84 @@ out_free:
         kfree(xent);
         return err;
 }
+
+static size_t security_listxattr(struct dentry *d, char *list, size_t list_size,
+                                 const char *name, size_t name_len, int flags)
+{
+        const int prefix_len = XATTR_SECURITY_PREFIX_LEN;
+        const size_t total_len = prefix_len + name_len + 1;
+
+        if (list && total_len <= list_size) {
+                memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
+                memcpy(list + prefix_len, name, name_len);
+                list[prefix_len + name_len] = '\0';
+        }
+
+        return total_len;
+}
+
+static int security_getxattr(struct dentry *d, const char *name, void *buffer,
+                      size_t size, int flags)
+{
+        return ubifs_getxattr(d, name, buffer, size);
+}
+
+static int security_setxattr(struct dentry *d, const char *name,
+                             const void *value, size_t size, int flags,
+                             int handler_flags)
+{
+        return ubifs_setxattr(d, name, value, size, flags);
+}
+
+static const struct xattr_handler ubifs_xattr_security_handler = {
+        .prefix = XATTR_SECURITY_PREFIX,
+        .list   = security_listxattr,
+        .get    = security_getxattr,
+        .set    = security_setxattr,
+};
+
+const struct xattr_handler *ubifs_xattr_handlers[] = {
+        &ubifs_xattr_security_handler,
+        NULL,
+};
+
+static int init_xattrs(struct inode *inode, const struct xattr *xattr_array,
+                      void *fs_info)
+{
+        const struct xattr *xattr;
+        char *name;
+        int err = 0;
+
+        for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+                name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
+                               strlen(xattr->name) + 1, GFP_NOFS);
+                if (!name) {
+                        err = -ENOMEM;
+                        break;
+                }
+                strcpy(name, XATTR_SECURITY_PREFIX);
+                strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+                err = setxattr(inode, name, xattr->value, xattr->value_len, 0);
+                kfree(name);
+                if (err < 0)
+                        break;
+        }
+
+        return err;
+}
+
+int ubifs_init_security(struct inode *dentry, struct inode *inode,
+                        const struct qstr *qstr)
+{
+        int err;
+
+        mutex_lock(&inode->i_mutex);
+        err = security_inode_init_security(inode, dentry, qstr,
+                                           &init_xattrs, 0);
+        mutex_unlock(&inode->i_mutex);
+
+        if (err)
+                ubifs_err("cannot initialize security for inode %lu, error %d",
+                          inode->i_ino, err);
+        return err;
+}