CIFS: Fix undefined behavior when mount fails
Fix double kfree() calls on the same pointers and cleanup mount code.
Reviewed-and-Tested-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 131afad..d1ed7f9 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -104,29 +104,23 @@
}
static int
-cifs_read_super(struct super_block *sb, struct cifs_sb_info *cifs_sb,
- void *data, struct smb_vol *volume_info, const char *devname,
- int silent)
+cifs_read_super(struct super_block *sb, struct smb_vol *volume_info,
+ const char *devname, int silent)
{
struct inode *inode;
+ struct cifs_sb_info *cifs_sb;
int rc = 0;
- /* BB should we make this contingent on mount parm? */
- sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
- sb->s_fs_info = cifs_sb;
+ cifs_sb = CIFS_SB(sb);
spin_lock_init(&cifs_sb->tlink_tree_lock);
cifs_sb->tlink_tree = RB_ROOT;
rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs", BDI_CAP_MAP_COPY);
- if (rc) {
- kfree(cifs_sb);
+ if (rc)
return rc;
- }
- cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages;
- if (data)
- cifs_sb->mountdata = data;
+ cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages;
rc = cifs_mount(sb, cifs_sb, volume_info, devname);
@@ -179,15 +173,7 @@
cifs_umount(sb, cifs_sb);
out_mount_failed:
- if (cifs_sb) {
- if (cifs_sb->mountdata) {
- kfree(cifs_sb->mountdata);
- cifs_sb->mountdata = NULL;
- }
- unload_nls(cifs_sb->local_nls);
- bdi_destroy(&cifs_sb->bdi);
- kfree(cifs_sb);
- }
+ bdi_destroy(&cifs_sb->bdi);
return rc;
}
@@ -553,7 +539,6 @@
struct cifs_sb_info *cifs_sb;
struct smb_vol *volume_info;
struct dentry *root;
- char *copied_data = NULL;
cFYI(1, "Devname: %s flags: %d ", dev_name, flags);
@@ -576,20 +561,23 @@
goto out;
}
- sb->s_flags = flags;
-
/*
* Copy mount params for use in submounts. Better to do
* the copy here and deal with the error before cleanup gets
* complicated post-mount.
*/
- copied_data = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
- if (copied_data == NULL) {
+ cifs_sb->mountdata = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
+ if (cifs_sb->mountdata == NULL) {
root = ERR_PTR(-ENOMEM);
goto err_out;
}
- rc = cifs_read_super(sb, cifs_sb, copied_data, volume_info, dev_name,
+ sb->s_flags = flags;
+ /* BB should we make this contingent on mount parm? */
+ sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
+ sb->s_fs_info = cifs_sb;
+
+ rc = cifs_read_super(sb, volume_info, dev_name,
flags & MS_SILENT ? 1 : 0);
if (rc) {
root = ERR_PTR(rc);
@@ -604,6 +592,8 @@
return root;
err_out:
+ kfree(cifs_sb->mountdata);
+ unload_nls(cifs_sb->local_nls);
kfree(cifs_sb);
deactivate_locked_super(sb);
cifs_cleanup_volume_info(&volume_info);