ubifs: xattr: Don't operate on deleted inodes

xattr operations can race with unlink and the following assert triggers:
UBIFS assert failed in ubifs_jnl_change_xattr at 1606 (pid 6256)

Fix this by checking i_nlink before working on the host inode.

Cc: <stable@vger.kernel.org>
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Richard Weinberger 2018-07-08 23:33:25 +02:00
parent 312c39bd6d
commit 11a6fc3dc7

View File

@ -152,6 +152,12 @@ static int create_xattr(struct ubifs_info *c, struct inode *host,
ui->data_len = size; ui->data_len = size;
mutex_lock(&host_ui->ui_mutex); mutex_lock(&host_ui->ui_mutex);
if (!host->i_nlink) {
err = -ENOENT;
goto out_noent;
}
host->i_ctime = current_time(host); host->i_ctime = current_time(host);
host_ui->xattr_cnt += 1; host_ui->xattr_cnt += 1;
host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm)); host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
@ -184,6 +190,7 @@ out_cancel:
host_ui->xattr_size -= CALC_XATTR_BYTES(size); host_ui->xattr_size -= CALC_XATTR_BYTES(size);
host_ui->xattr_names -= fname_len(nm); host_ui->xattr_names -= fname_len(nm);
host_ui->flags &= ~UBIFS_CRYPT_FL; host_ui->flags &= ~UBIFS_CRYPT_FL;
out_noent:
mutex_unlock(&host_ui->ui_mutex); mutex_unlock(&host_ui->ui_mutex);
out_free: out_free:
make_bad_inode(inode); make_bad_inode(inode);
@ -235,6 +242,12 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
mutex_unlock(&ui->ui_mutex); mutex_unlock(&ui->ui_mutex);
mutex_lock(&host_ui->ui_mutex); mutex_lock(&host_ui->ui_mutex);
if (!host->i_nlink) {
err = -ENOENT;
goto out_noent;
}
host->i_ctime = current_time(host); host->i_ctime = current_time(host);
host_ui->xattr_size -= CALC_XATTR_BYTES(old_size); host_ui->xattr_size -= CALC_XATTR_BYTES(old_size);
host_ui->xattr_size += CALC_XATTR_BYTES(size); host_ui->xattr_size += CALC_XATTR_BYTES(size);
@ -256,6 +269,7 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
out_cancel: out_cancel:
host_ui->xattr_size -= CALC_XATTR_BYTES(size); host_ui->xattr_size -= CALC_XATTR_BYTES(size);
host_ui->xattr_size += CALC_XATTR_BYTES(old_size); host_ui->xattr_size += CALC_XATTR_BYTES(old_size);
out_noent:
mutex_unlock(&host_ui->ui_mutex); mutex_unlock(&host_ui->ui_mutex);
make_bad_inode(inode); make_bad_inode(inode);
out_free: out_free:
@ -482,6 +496,12 @@ static int remove_xattr(struct ubifs_info *c, struct inode *host,
return err; return err;
mutex_lock(&host_ui->ui_mutex); mutex_lock(&host_ui->ui_mutex);
if (!host->i_nlink) {
err = -ENOENT;
goto out_noent;
}
host->i_ctime = current_time(host); host->i_ctime = current_time(host);
host_ui->xattr_cnt -= 1; host_ui->xattr_cnt -= 1;
host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm)); host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm));
@ -501,6 +521,7 @@ out_cancel:
host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm)); host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
host_ui->xattr_names += fname_len(nm); host_ui->xattr_names += fname_len(nm);
out_noent:
mutex_unlock(&host_ui->ui_mutex); mutex_unlock(&host_ui->ui_mutex);
ubifs_release_budget(c, &req); ubifs_release_budget(c, &req);
make_bad_inode(inode); make_bad_inode(inode);
@ -540,6 +561,9 @@ static int ubifs_xattr_remove(struct inode *host, const char *name)
ubifs_assert(inode_is_locked(host)); ubifs_assert(inode_is_locked(host));
if (!host->i_nlink)
return -ENOENT;
if (fname_len(&nm) > UBIFS_MAX_NLEN) if (fname_len(&nm) > UBIFS_MAX_NLEN)
return -ENAMETOOLONG; return -ENAMETOOLONG;