4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jaegeuk Kim <[email protected]> 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 <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]> Cc: Theodore Ts'o <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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);
