ANDROID: sdcardfs: Move directory unlock before touch
This removes a deadlock under low memory conditions.
filp_open can call lookup_slow, which will attempt to
lock the parent.
Change-Id: I940643d0793f5051d1e79a56f4da2fa8ca3d8ff7
Signed-off-by: Daniel Rosenberg <drosen@google.com>
diff --git a/fs/sdcardfs/inode.c b/fs/sdcardfs/inode.c
index 67bcee2..3c353c9 100644
--- a/fs/sdcardfs/inode.c
+++ b/fs/sdcardfs/inode.c
@@ -296,14 +296,17 @@
copied_fs = copy_fs_struct(current->fs);
if (!copied_fs) {
err = -ENOMEM;
+ unlock_dir(lower_parent_dentry);
goto out_unlock;
}
current->fs = copied_fs;
current->fs->umask = 0;
err = vfs_mkdir(d_inode(lower_parent_dentry), lower_dentry, mode);
- if (err)
+ if (err) {
+ unlock_dir(lower_parent_dentry);
goto out;
+ }
/* if it is a local obb dentry, setup it with the base obbpath */
if(need_graft_path(dentry)) {
@@ -325,14 +328,18 @@
}
err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, pi->userid);
- if (err)
+ if (err) {
+ unlock_dir(lower_parent_dentry);
goto out;
+ }
fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
fsstack_copy_inode_size(dir, d_inode(lower_parent_dentry));
/* update number of links on parent directory */
set_nlink(dir, sdcardfs_lower_inode(dir)->i_nlink);
+ unlock_dir(lower_parent_dentry);
+
if ((!sbi->options.multiuser) && (!strcasecmp(dentry->d_name.name, "obb"))
&& (pi->perm == PERM_ANDROID) && (pi->userid == 0))
make_nomedia_in_obb = 1;
@@ -352,7 +359,6 @@
current->fs = saved_fs;
free_fs_struct(copied_fs);
out_unlock:
- unlock_dir(lower_parent_dentry);
sdcardfs_put_lower_path(dentry, &lower_path);
out_revert:
REVERT_CRED(saved_cred);