From: Al Viro <viro@www.linux.org.uk>
In open_namei() exit_dput: we have mntput() done in the wrong order -
if nd->mnt != path.mnt we end up doing
mntput(nd->mnt);
nd->mnt = path.mnt;
dput(nd->dentry);
mntput(nd->mnt);
which drops nd->dentry too late. Fixed by having path.mnt go first.
That allows to switch O_NOFOLLOW under if (__follow_mount(...)) back
to exit_dput, while we are at it.
Fix for early-mntput() race + equivalent transformation.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
fs/namei.c | 10 +++-------
1 files changed, 3 insertions(+), 7 deletions(-)
diff -puN fs/namei.c~namei-fixes-13-19 fs/namei.c
--- 25/fs/namei.c~namei-fixes-13-19 Fri May 20 15:42:31 2005
+++ 25-akpm/fs/namei.c Fri May 20 15:42:31 2005
@@ -1501,11 +1501,8 @@ do_last:
if (__follow_mount(&path)) {
error = -ELOOP;
- if (flag & O_NOFOLLOW) {
- dput(path.dentry);
- mntput(path.mnt);
- goto exit;
- }
+ if (flag & O_NOFOLLOW)
+ goto exit_dput;
}
error = -ENOENT;
if (!path.dentry->d_inode)
@@ -1530,8 +1527,7 @@ ok:
exit_dput:
dput(path.dentry);
if (nd->mnt != path.mnt)
- mntput(nd->mnt);
- nd->mnt = path.mnt;
+ mntput(path.mnt);
exit:
path_release(nd);
return error;
_