From 3283aeeace5e8965bf8d0338b278b5a2c818d743 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Tue, 5 Jul 2016 17:32:29 -0400 Subject: [PATCH] Revert "ecryptfs: forbid opening files without mmap handler" 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. Change-Id: I78753c9cadef7b43cd277d4827a096b45697c288 Signed-off-by: Jeff Mahoney Cc: stable@vger.kernel.org Signed-off-by: Tyler Hicks Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git Git-commit: 78c4e172412de5d0456dc00d2b34050aa0b683b5 Signed-off-by: Dennis Cagle --- fs/ecryptfs/kthread.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c index e818f5ac7a26..866bb18efefe 100644 --- a/fs/ecryptfs/kthread.c +++ b/fs/ecryptfs/kthread.c @@ -25,7 +25,6 @@ #include #include #include -#include #include "ecryptfs_kernel.h" struct ecryptfs_open_req { @@ -148,7 +147,7 @@ int ecryptfs_privileged_open(struct file **lower_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 **lower_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; }