summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJeff Mahoney <jeffm@suse.com>2016-07-05 17:32:29 -0400
committerSasha Levin <alexander.levin@verizon.com>2016-07-19 15:49:44 -0400
commitf1e8b05914912c9a6309c450f266aa21d5667524 (patch)
treeea7957883e6d6b042c4be85f675fdc9d2d4f24fd
parent9c9497d5b1e93187ea6c0cdca3f3706fd7713acf (diff)
downloadlwn-f1e8b05914912c9a6309c450f266aa21d5667524.tar.gz
lwn-f1e8b05914912c9a6309c450f266aa21d5667524.zip
Revert "ecryptfs: forbid opening files without mmap handler"
[ Upstream commit 78c4e172412de5d0456dc00d2b34050aa0b683b5 ] 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@suse.com> Cc: stable@vger.kernel.org Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
-rw-r--r--fs/ecryptfs/kthread.c13
1 files 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 <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 **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;
}