This is a note to let you know that I've just added the patch titled ext4/fscrypto: avoid RCU lookup in d_revalidate to the 4.4-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: ext4-fscrypto-avoid-rcu-lookup-in-d_revalidate.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 03a8bb0e53d9562276045bdfcf2b5de2e4cff5a1 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Date: Tue, 12 Apr 2016 16:05:36 -0700 Subject: ext4/fscrypto: avoid RCU lookup in d_revalidate From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> commit 03a8bb0e53d9562276045bdfcf2b5de2e4cff5a1 upstream. As Al pointed, d_revalidate should return RCU lookup before using d_inode. This was originally introduced by: commit 34286d666230 ("fs: rcu-walk aware d_revalidate method"). Reported-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Cc: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ext4/crypto.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/fs/ext4/crypto.c +++ b/fs/ext4/crypto.c @@ -34,6 +34,7 @@ #include <linux/random.h> #include <linux/scatterlist.h> #include <linux/spinlock_types.h> +#include <linux/namei.h> #include "ext4_extents.h" #include "xattr.h" @@ -481,6 +482,9 @@ static int ext4_d_revalidate(struct dent struct ext4_crypt_info *ci; int dir_has_key, cached_with_key; + if (flags & LOOKUP_RCU) + return -ECHILD; + dir = dget_parent(dentry); if (!ext4_encrypted_inode(d_inode(dir))) { dput(dir); Patches currently in stable-queue which might be from jaegeuk@xxxxxxxxxx are queue-4.4/ext4-fscrypto-avoid-rcu-lookup-in-d_revalidate.patch