This is a note to let you know that I've just added the patch titled

    debugfs: leave freeing a symlink body until inode eviction

to the 3.19-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     debugfs-leave-freeing-a-symlink-body-until-inode-eviction.patch
and it can be found in the queue-3.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 0db59e59299f0b67450c5db21f7f316c8fb04e84 Mon Sep 17 00:00:00 2001
From: Al Viro <[email protected]>
Date: Sat, 21 Feb 2015 22:05:11 -0500
Subject: debugfs: leave freeing a symlink body until inode eviction

From: Al Viro <[email protected]>

commit 0db59e59299f0b67450c5db21f7f316c8fb04e84 upstream.

As it is, we have debugfs_remove() racing with symlink traversals.
Supply ->evict_inode() and do freeing there - inode will remain
pinned until we are done with the symlink body.

And rip the idiocy with checking if dentry is positive right after
we'd verified debugfs_positive(), which is a stronger check...

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/debugfs/inode.c |   34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -246,10 +246,19 @@ static int debugfs_show_options(struct s
        return 0;
 }
 
+static void debugfs_evict_inode(struct inode *inode)
+{
+       truncate_inode_pages_final(&inode->i_data);
+       clear_inode(inode);
+       if (S_ISLNK(inode->i_mode))
+               kfree(inode->i_private);
+}
+
 static const struct super_operations debugfs_super_operations = {
        .statfs         = simple_statfs,
        .remount_fs     = debugfs_remount,
        .show_options   = debugfs_show_options,
+       .evict_inode    = debugfs_evict_inode,
 };
 
 static int debug_fill_super(struct super_block *sb, void *data, int silent)
@@ -466,23 +475,14 @@ static int __debugfs_remove(struct dentr
        int ret = 0;
 
        if (debugfs_positive(dentry)) {
-               if (dentry->d_inode) {
-                       dget(dentry);
-                       switch (dentry->d_inode->i_mode & S_IFMT) {
-                       case S_IFDIR:
-                               ret = simple_rmdir(parent->d_inode, dentry);
-                               break;
-                       case S_IFLNK:
-                               kfree(dentry->d_inode->i_private);
-                               /* fall through */
-                       default:
-                               simple_unlink(parent->d_inode, dentry);
-                               break;
-                       }
-                       if (!ret)
-                               d_delete(dentry);
-                       dput(dentry);
-               }
+               dget(dentry);
+               if (S_ISDIR(dentry->d_inode->i_mode))
+                       ret = simple_rmdir(parent->d_inode, dentry);
+               else
+                       simple_unlink(parent->d_inode, dentry);
+               if (!ret)
+                       d_delete(dentry);
+               dput(dentry);
        }
        return ret;
 }


Patches currently in stable-queue which might be from [email protected] 
are

queue-3.19/procfs-fix-race-between-symlink-removals-and-traversals.patch
queue-3.19/debugfs-leave-freeing-a-symlink-body-until-inode-eviction.patch
queue-3.19/autofs4-copy_dev_ioctl-keep-the-value-of-size-we-d-used-for-allocation.patch
queue-3.19/autofs4-wrong-format-for-printing-dentry.patch
queue-3.19/sunrpc-fix-braino-in-poll.patch
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