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>
This commit is contained in:
Linus Torvalds 2012-07-07 10:17:00 -07:00
Родитель cd6407fe22
Коммит 332a2e1244
1 изменённых файлов: 3 добавлений и 3 удалений

Просмотреть файл

@ -397,10 +397,10 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
{
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 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
if (!error)
set_fs_pwd(current->fs, &file->f_path);
out_putf:
fput(file);
fput_light(file, fput_needed);
out:
return error;
}