Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull mount leak fix from Al Viro:
 "Regression fix for the syscalls-for-init series - fix a leak of a 'struct path'"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: fix a struct path leak in path_umount
This commit is contained in:
Linus Torvalds 2020-08-07 21:03:25 -07:00
Родитель 049eb096da 25ccd24ffd
Коммит d57b2b5bc4
1 изменённых файлов: 18 добавлений и 14 удалений

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@ -1706,34 +1706,38 @@ static inline bool may_mandlock(void)
}
#endif
int path_umount(struct path *path, int flags)
static int can_umount(const struct path *path, int flags)
{
struct mount *mnt;
int retval;
struct mount *mnt = real_mount(path->mnt);
if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW))
return -EINVAL;
if (!may_mount())
return -EPERM;
mnt = real_mount(path->mnt);
retval = -EINVAL;
if (path->dentry != path->mnt->mnt_root)
goto dput_and_out;
return -EINVAL;
if (!check_mnt(mnt))
goto dput_and_out;
return -EINVAL;
if (mnt->mnt.mnt_flags & MNT_LOCKED) /* Check optimistically */
goto dput_and_out;
retval = -EPERM;
return -EINVAL;
if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN))
goto dput_and_out;
return -EPERM;
return 0;
}
int path_umount(struct path *path, int flags)
{
struct mount *mnt = real_mount(path->mnt);
int ret;
ret = can_umount(path, flags);
if (!ret)
ret = do_umount(mnt, flags);
retval = do_umount(mnt, flags);
dput_and_out:
/* we mustn't call path_put() as that would clear mnt_expiry_mark */
dput(path->dentry);
mntput_no_expire(mnt);
return retval;
return ret;
}
static int ksys_umount(char __user *name, int flags)