[PATCH] permission checks for chdir need special treatment only on the last step
... so we ought to pass MAY_CHDIR to vfs_permission() instead of having
it triggered on every step of preceding pathname resolution. LOOKUP_CHDIR
is killed by that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/open.c b/fs/open.c
index b2e4c93..8e02d42 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -501,12 +501,11 @@
struct nameidata nd;
int error;
- error = __user_walk(filename,
- LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd);
+ error = __user_walk(filename, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &nd);
if (error)
goto out;
- error = vfs_permission(&nd, MAY_EXEC);
+ error = vfs_permission(&nd, MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;