This is a note to let you know that I've just added the patch titled Revert "ecryptfs: forbid opening files without mmap handler" to the 4.6-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: revert-ecryptfs-forbid-opening-files-without-mmap-handler.patch and it can be found in the queue-4.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 78c4e172412de5d0456dc00d2b34050aa0b683b5 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney <jeffm@xxxxxxxx> Date: Tue, 5 Jul 2016 17:32:29 -0400 Subject: Revert "ecryptfs: forbid opening files without mmap handler" From: Jeff Mahoney <jeffm@xxxxxxxx> commit 78c4e172412de5d0456dc00d2b34050aa0b683b5 upstream. This reverts commit 2f36db71009304b3f0b95afacd8eba1f9f046b87. It fixed a local root exploit but also introduced a dependency on the lower file system implementing an mmap operation just to open a file, which is a bit of a heavy hammer. The right fix is to have mmap depend on the existence of the mmap handler instead. Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx> Signed-off-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ecryptfs/kthread.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) --- a/fs/ecryptfs/kthread.c +++ b/fs/ecryptfs/kthread.c @@ -25,7 +25,6 @@ #include <linux/slab.h> #include <linux/wait.h> #include <linux/mount.h> -#include <linux/file.h> #include "ecryptfs_kernel.h" struct ecryptfs_open_req { @@ -148,7 +147,7 @@ int ecryptfs_privileged_open(struct file flags |= IS_RDONLY(d_inode(lower_dentry)) ? O_RDONLY : O_RDWR; (*lower_file) = dentry_open(&req.path, flags, cred); if (!IS_ERR(*lower_file)) - goto have_file; + goto out; if ((flags & O_ACCMODE) == O_RDONLY) { rc = PTR_ERR((*lower_file)); goto out; @@ -166,16 +165,8 @@ int ecryptfs_privileged_open(struct file mutex_unlock(&ecryptfs_kthread_ctl.mux); wake_up(&ecryptfs_kthread_ctl.wait); wait_for_completion(&req.done); - if (IS_ERR(*lower_file)) { + if (IS_ERR(*lower_file)) rc = PTR_ERR(*lower_file); - goto out; - } -have_file: - if ((*lower_file)->f_op->mmap == NULL) { - fput(*lower_file); - *lower_file = NULL; - rc = -EMEDIUMTYPE; - } out: return rc; } Patches currently in stable-queue which might be from jeffm@xxxxxxxx are queue-4.6/ecryptfs-don-t-allow-mmap-when-the-lower-fs-doesn-t-support-it.patch queue-4.6/revert-ecryptfs-forbid-opening-files-without-mmap-handler.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html