[PATCH 02/10] xfs: Fix open flag handling in open_by_handle code

Dave Chinner
2012-03-07T04:50:46Z

From: Dave Chinner <dchinner@redhat.com>

Sparse identified some unsafe handling of open flags in the xfs open
by handle ioctl code. Update the code to use the correct access
macros to ensure that we handle the open flags correctly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_ioctl.c | 14 +++++---------
1 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 76f3ca5..8dc5fe1 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -209,6 +209,7 @@ xfs_open_by_handle(
struct file *filp;
struct inode *inode;
struct dentry *dentry;
+ fmode_t fmode;

if (!capable(CAP_SYS_ADMIN))
return -XFS_ERROR(EPERM);
@@ -228,26 +229,21 @@ xfs_open_by_handle(
hreq->oflags |= O_LARGEFILE;
#endif

- /* Put open permission in namei format. */
permflag = hreq->oflags;
- if ((permflag+1) & O_ACCMODE)
- permflag++;
- if (permflag & O_TRUNC)
- permflag |= 2;
-
+ fmode = OPEN_FMODE(permflag);
if ((!(permflag & O_APPEND) || (permflag & O_TRUNC)) &&
- (permflag & FMODE_WRITE) && IS_APPEND(inode)) {
+ (fmode & FMODE_WRITE) && IS_APPEND(inode)) {
error = -XFS_ERROR(EPERM);
goto out_dput;
}

- if ((permflag & FMODE_WRITE) && IS_IMMUTABLE(inode)) {
+ if ((fmode & FMODE_WRITE) && IS_IMMUTABLE(inode)) {
error = -XFS_ERROR(EACCES);
goto out_dput;
}

/* Can't write directories. */
- if (S_ISDIR(inode->i_mode) && (permflag & FMODE_WRITE)) {
+ if (S_ISDIR(inode->i_mode) && (fmode & FMODE_WRITE)) {
error = -XFS_ERROR(EISDIR);
goto out_dput;
}
--
1.7.9