vfs: make O_PATH file descriptors usable for 'fchdir()'
We already use them for openat() and friends, but fchdir() also wants to
be able to use O_PATH file descriptors. This should make it comparable
to the O_SEARCH of Solaris. In particular, O_PATH allows you to access
(not-quite-open) a directory you don't have read persmission to, only
execute permission.
Noticed during development of multithread support for ksh93.
Reported-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org # O_PATH introduced in 3.0+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/open.c b/fs/open.c
index d6c79a0..1540632 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -397,10 +397,10 @@
{
struct file *file;
struct inode *inode;
- int error;
+ int error, fput_needed;
error = -EBADF;
- file = fget(fd);
+ file = fget_raw_light(fd, &fput_needed);
if (!file)
goto out;
@@ -414,7 +414,7 @@
if (!error)
set_fs_pwd(current->fs, &file->f_path);
out_putf:
- fput(file);
+ fput_light(file, fput_needed);
out:
return error;
}
